CN106732688A

CN106732688A - Composite magnetic visible light catalyst silver silver halide BiOX cobalt ferrite and preparation method thereof

Info

Publication number: CN106732688A
Application number: CN201611255417.8A
Authority: CN
Inventors: 张安超; 张立享; 路好; 王�华; 万剑峰; 朱崎峰; 王发辉; 刘志超
Original assignee: Henan University of Technology
Current assignee: Henan University of Technology
Priority date: 2016-12-30
Filing date: 2016-12-30
Publication date: 2017-05-31
Anticipated expiration: 2036-12-30
Also published as: CN106732688B

Abstract

The present invention provides a kind of composite magnetic visible light catalyst silver silver halide BiOX cobalt ferrite and preparation method thereof, and it provides a kind of recyclable magnetic photocatalyst Ag AgX BiOX CoFe₂O₄（X=Cl、Br、I）, the catalyst is by simple substance Ag, AgX（X=Cl、Br、I）、BiOX（X=Cl、Br、I）And CoFe₂O₄It is composited, many components are coupled with beneficial to photo-generate electron-hole to efficiently separating, more oxidizing species can be produced, so that strengthen the oxidation activity of visible light catalyst, magnetic carrier CoFe₂O₄Doping can make the visible light catalyst there is sufficiently strong magnetic to reclaim ability, can recycled for multiple times, so as to reduce flue gas demercuration cost, improve the environmental-protecting performance of visible light catalyst.

Description

Composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite and its system Preparation Method

Technical field：

The invention belongs to environmental pollution prevention and control technical field, and in particular to a kind of composite magnetic visible light catalyst silver-silver halide- BiOX-cobalt ferrite and preparation method thereof.

Background technology：

Mercury is made due to its hypertoxicity, persistence, biological accumulation and the remote transfer ability of air to ecological environment and human health Into greatly harm.Coal combustion is considered as the main source of mercury in air.Because the energy production structure of China is main with coal Based on charcoal, coal in China total quantity consumed in 2014 is about 3,500,000,000 tons of standard coals, ratio of the coal in primary energy consumption structure Maintain 60% or so, although mercury average content only has 0.22mg/kg in coal in China, but because coal consumption amount is huge, it is coal-fired The mercury discharged in flue gas can not be ignored to ecological environment with the influence of human health.To the issuing and implementation of this national environmental protection portion 《Fossil-fuel power plant atmospheric pollutant emission standard GB13223-2011》The clear stipulaties discharge standard of mercury in flue gas and its compound.

Mercury In Coal Combustion Flue Gas are main to be existed with three kinds of forms：Elemental Mercury（Hg⁰）, oxidation state bivalent mercury（Hg²⁺）And particulate form Mercury（Hg^p）.Wherein oxidation state mercury（Hg²⁺）It is soluble in water, can effectively be removed by existing wet flue gas desulfurizer；Particulate form Mercury（Hg^p）It is easy to effectively be removed by existing electrostatic dust collection equipment；And Elemental Mercury（Hg⁰）Because fusing point is low, volatile and indissoluble Yu Shui, it is difficult to be removed by existing flue gas pollutant control method.Therefore, Elemental Mercury（Hg⁰）Effective removing be current combustion The a great problem in flue-gas pollutant catabolic gene field is also the study hotspot that atmosphere pollution administers field.

At present, the Elemental Mercury in flue gas is removed（Hg⁰）, generally first by Elemental Mercury（Hg⁰）It is oxidized to bivalent mercury（Hg²⁺）, Then removed by existing wet flue gas desulfurizer again.When by elemental mercury oxidation into bivalent mercury, light is generally used The method of chemical catalysis, using visible ray or ultraviolet light catalyst, makes visible light catalyst produce photo-generate electron-hole pair （e⁻+h⁺）, photo-generate electron-hole pair and oxygen or water reaction generation have the superoxipe ion of strong oxidizing property（^•O₂ ^—）Or hydroxyl（^• OH）, Elemental Mercury（Hg⁰）With superoxipe ion（^•O₂ ^—）Or hydroxyl（^•OH）It is oxidized to bivalent mercury（Hg²⁺）, then by existing wet Method flue gas desulfurization device is removed.

Existing wide variety of visible light catalyst is mostly one-component structure, such as Ag of simple substance, the AgX (X of one-component =Cl, Br, I) or one-component BiOX (X=Cl, Br, I), the light that the visible light catalyst of one-component is produced under visible light illumination Raw electron hole pair is easily combined, and causes its catalysis activity weaker, causes the light-catalyzed reaction time long, and flue gas demercuration efficiency is low Under, meanwhile, the high cost of existing visible light catalyst and recovery are difficult.

The content of the invention：

In sum, in order to overcome the shortcomings of prior art problem, the invention provides a kind of composite magnetic visible light catalyst Silver-silver halide-BiOX-cobalt ferrite and preparation method thereof, it provides a kind of recyclable magnetic photocatalyst Ag- AgX-BiOX-CoFe₂O₄（X=Cl、Br、I）, the catalyst is by simple substance Ag, AgX（X=Cl、Br、I）、BiOX（X=Cl、Br、I）And CoFe₂O₄It is composited, many components are coupled with beneficial to photo-generate electron-hole to efficiently separating, more strong oxidizing property can be produced Material, so that strengthen the oxidation activity of visible light catalyst, magnetic carrier CoFe₂O₄Doping can make visible light catalyst have foot Enough strong magnetic reclaims ability, can recycled for multiple times, so as to reduce flue gas demercuration cost, improve the environmental protection of visible light catalyst Performance.

In order to solve the above technical problems, the technical proposal of the invention is realized in this way：

A kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, wherein：By Ag, AgX（X=Cl、Br、 I）、BiOX（X=Cl、Br、I）And CoFe₂O₄Composition.

Technical scheme may also is that realization：By Ag, AgI, BiOI and CoFe₂O₄Composition, CoFe₂O₄、 The weight ratio of AgI and BiOI is CoFe₂O₄：AgI：BiOI=1：（1~10）：（1~10）, the weight ratio of Ag and AgI is 0.1% ~ 10%.

Technical scheme may also is that realization：By Ag, AgI, BiOI and CoFe₂O₄Composition, CoFe₂O₄、 The weight ratio of AgI and BiOI is CoFe₂O₄：AgI：BiOI=1：1.5：2.5, Ag is 1 ~ 5% with the weight ratio of AgI.

Technical scheme may also is that realization：By Ag, AgCl, BiOCl and CoFe₂O₄Composition, CoFe₂O₄, AgCl and BiOCl weight ratio be CoFe₂O₄：AgCl：BiOCl=1：（1~5）：（1~10）, the weight of Ag and AgCl Than being 0.1% ~ 10%.

Technical scheme may also is that realization：By Ag, AgCl, BiOCl and CoFe₂O₄Composition, CoFe₂O₄, AgCl and BiOCl weight ratio be CoFe₂O₄：AgCl：BiOCl=1：1：7, Ag is 1 ~ 5% with the weight ratio of AgCl.

Technical scheme may also is that realization：By Ag, AgBr, BiOBr and CoFe₂O₄Composition, CoFe₂O₄, AgBr and BiOBr weight ratio be CoFe₂O₄：AgBr：BiOBr=1：（1~10）：（1~20）, the weight of Ag and AgBr Than being 0.1% ~ 10%.

Technical scheme may also is that realization：By Ag, AgBr, BiOBr and CoFe₂O₄Composition, CoFe₂O₄, AgBr and BiOBr weight ratio be CoFe₂O₄：AgBr：BiOBr=1：2：4, Ag is 1 ~ 5% with the weight ratio of AgBr.

A kind of preparation method of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, wherein：Including Following processing step：

First, magnetic corpuscular CoFe is prepared₂O₄

（1）, by a moles of Co (NO₃)₂·6H₂O and 2a moles of Fe (NO₃)₃·9H₂O is dissolved in the deionized water of 100 ~ 150mL And uniform stirring, obtain the mixed solution A of cobalt nitrate and ferric nitrate；

（2）, 8a moles of NaOH be dissolved in the deionized water of 100 ~ 150mL obtain solution B；

（3）, solution B is added slowly in solution A adjust the pH value of solution A, solution ph is maintained between 12 ~ 14, add Plus during add while stirring, addition finish after continue stir 2 ~ 3 hours, obtained solution C；

（4）, solution C heated, solution C is chemically reacted, after completion of the reaction, products therefrom natural cooling will be reacted To room temperature, then wash 3 ~ 5 times, finally hydro-thermal reaction product be placed in 60 ~ 80 °C of baking oven and be vacuum dried 24 ~ 48 hours, Magnetic CoFe will be obtained after the grinding of dried product, screening₂O₄Microparticle；

2nd, AgX-BiOX-CoFe is prepared₂O₄（X=Cl、Br、I）Magnetic suspension solution

（1）, converse a certain amount of AgX-BiOX-CoFe by weight₂O₄（X=Cl、Br、I）The mole and Bi of Ag in catalyst Mole, the mole of the mole of Ag and Bi is multiplied by AgNO respectively₃With Bi (NO₃)₃·5H₂Needed for the molecular weight of O is obtained Want AgNO₃With Bi (NO₃)₃·5H₂The weight of O, and weigh the AgNO of corresponding weight₃With Bi (NO₃)₃·5H₂O；

（2）, the AgNO that will weigh₃With Bi (NO₃)₃·5H₂O is dissolved in the glacial acetic acid aqueous solution of 100 ~ 800mL, and uniform stirring, Obtain the mixed solution D of silver nitrate and bismuth nitrate under acid condition；

（3）, will in the step of weighing by weight one prepare magnetic CoFe₂O₄Microparticle is added in solution D, and mixing is stirred Mix 30 ~ 60 minutes, obtained solution E；

（4）, by above-mentioned steps（1）In the mole of Ag that calculates be added with the mole of Bi, draw required KX（X=Cl、 Br、I）Mole, according to KX（X=Cl、Br、I）Molar amount calculate required KX（X=Cl、Br、I）Weight；According to this Weight weighs KX（X=Cl、Br、I）, it is dissolved in the water of 20 ~ 200mL, then the KX solution is added drop-wise in solution E, drip Plus during be added dropwise while stirring, and continuously stirred after completion of dropping 2 ~ 3 hours, stand at least 12 hours again afterwards, be obtained outstanding Floating solution F；

3rd, magnetic photocatalyst Ag-AgX-BiOX-CoFe is prepared₂O₄（X=Cl、Br、I）

（1）, obtained aaerosol solution F in step 2 is placed under the ultraviolet lamp of 10 ~ 100W and is irradiated and is stirred 1 ~ 10 hour；

（2）, the aaerosol solution F after irradiation stood, the then sediment in solid-liquid separation aaerosol solution F；

（3）, with the mixed solution cyclic washing sediment 3 ~ 5 times of ethanol and water, 60 ~ 80 °C of baking oven is put the precipitate in afterwards Middle vacuum drying 12 ~ 24 hours, finally by the grinding of dried sediment, screening, is obtained magnetic photocatalyst Ag-AgX- BiOX-CoFe₂O₄（X=Cl、Br、I）.

Technical scheme may also is that realization：Step one（4）It is middle that solution C is put into hydrothermal reaction kettle In, then hydrothermal reaction kettle being put into baking oven and is heated, oven temperature is 150 ~ 200 °C, and the heat time is 8 ~ 16 hours.

Technical scheme may also is that realization：Step 2（1）In, in the aqueous solution of described glacial acetic acid The volume fraction of glacial acetic acid is 10% ~ 50%.

Beneficial effects of the present invention are：

The present invention provides a kind of recyclable magnetic photocatalyst Ag-AgX-BiOX- CoFe₂O₄（X=Cl、Br、I）, should Catalyst is by simple substance Ag, AgX, BiOX and CoFe₂O₄It is composited, using Ag, AgX, BiOX and CoFe₂O₄Between four preferably Can band mating structure, be conducive to photo-generate electron-hole to efficiently separating, the electronics and air of photo-generate electron-hole centering In oxygen generate substantial amounts of super oxygen root free radical（^•O₂ ^—）, raw electron hole centering hole can generate great amount of hydroxy group with water Free radical（^•OH）；Hydroxyl radical free radical（^•OH）, super oxygen root free radical（^•O₂ ^—）And hole（h⁺）With very strong oxidability, can Efficiently by Elemental Mercury Hg⁰It is oxidized to bivalent mercury Hg²⁺, and magnetic material CoFe₂O₄Addition, make visible light catalyst possess compared with Strong magnetic reclaims ability, reusable, significantly reduces the use cost of catalyst.Can recycled for multiple times so that Flue gas demercuration cost is reduced, the environmental-protecting performance of visible light catalyst is improved, is visible ray due to what is introduced, so the demercuration technology Not only clean but also energy-conserving and environment-protective, were conducive to large-scale use.

Brief description of the drawings：

Fig. 1 is that embodiments of the invention one, embodiment two, embodiment three, comparative example one, comparative example two and contrast are real Apply three or four kinds of catalyst demercuration efficiency comparison diagrams of example；

Fig. 2 is that embodiments of the invention four, embodiment five, embodiment six, comparative example one, comparative example four and contrast are real Apply a May 4th kind catalyst demercuration efficiency comparison diagram；

Fig. 3 is that embodiments of the invention seven, embodiment eight, embodiment nine, comparative example one, comparative example six and contrast are real Apply seven or four kinds of catalyst demercuration efficiency comparison diagrams of example.

Specific embodiment

Below in conjunction with the accompanying drawings and embodiment the present invention is described in further detail.

Embodiment one

A kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, by Ag, AgCl, BiOCl and CoFe₂O₄Composition, CoFe₂O₄, AgCl and BiOCl weight ratio be：

CoFe₂O₄：AgCl：BiOCl=1：1：1, Ag is 0.1% ~ 2% with the weight ratio of AgCl.

The preparation method of above-mentioned composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, wherein：Including Following processing step：

First, magnetic corpuscular CoFe is prepared₂O₄

（1）, by the Co of 0.042 mol（NO₃）₂·6H₂The Fe of O and 0.084mol（NO₃）₃·9H₂O dissolves in the deionization of 100mL In water and uniform stirring, the mixed solution A of cobalt nitrate and ferric nitrate is obtained；

（2）, the NaOH of 0.34 mol be dissolved in the deionized water of 100mL obtain solution B；

（3）, solution B is added slowly in solution A adjust the pH value of solution A, solution ph is maintained between 12 ~ 14, add Plus during add while stirring, addition finish after continue stir 2 hours, obtained solution C；

（4）, solution C is put into hydrothermal reaction kettle and then hydrothermal reaction kettle is put into baking oven and heated, oven temperature is 180 ° C, the heat time is 8 hours, after completion of the reaction, reaction products therefrom is naturally cooled into room temperature, then washing 3 ~ 5 times, finally Hydro-thermal reaction product is placed in 80 °C of baking oven and is vacuum dried 24 hours, magnetic will be obtained after the grinding of dried product, screening Property CoFe₂O₄Microparticle.

2nd, AgCl-BiOCl-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：1：1 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOCl of the AgCl of 1g and 1g are counted Calculate, the weight according to the AgCl for choosing obtains the mole of AgCl for 0.00697mol, then Ag moles divided by the molecular weight of AgCl It is 0.00697mol；Weight according to the BiOCl for choosing obtains molecular weight divided by BiOCl, and the mole for obtaining BiOCl is 0.00384mol, then the mole of Bi is 0.00384mol, needed for then the mole 0.00697mol according to Ag is calculated AgNO₃Weight be 1.184 grams, the mole 0.00384mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 1.863 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 1.184 grams of AgNO₃With 1.863 grams of Bi (NO₃)₃· 5H₂O；

（2）, the AgNO that will weigh₃With Bi (NO₃)₃·5H₂During the volume ratio that O dissolves in 200mL is 20% glacial acetic acid aqueous solution, and Uniform stirring, obtains the mixed solution D of silver nitrate and bismuth nitrate under acid condition；

（3）, will in the step of weighing one prepare 1 gram of magnetic CoFe₂O₄Microparticle is added in solution D, and mixing 30 ~ 60 minutes, obtained solution E；

（4）, by above-mentioned steps（1）In the mole 0.00384mol phases of the mole 0.00697mol and Bi of Ag that calculate Plus, the mole of the KCl needed for drawing is 0.01081mol, and the weight that the molar amount according to KCl calculates required KCl is 0.548g；

0.548 gram of KCl is weighed, is dissolved in the water of 20mL, then the KCl solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 36W and is irradiated and is stirred 2 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgCl, and it is 0.1% ~ 2% with the weight ratio of AgCl.

Embodiment two

CoFe₂O₄：AgCl：BiOCl=1：5：10, Ag is 2% ~ 5% with the weight ratio of AgCl.

First, magnetic corpuscular CoFe is prepared₂O₄

（1）, by the Co (NO of 0.042 mol₃)₂·6H₂Fe (the NO of O and 0.084 mol₃)₃·9H₂O dissolves in the deionization of 100mL In water and uniform stirring, the mixed solution A of cobalt nitrate and ferric nitrate is obtained；

（4）, solution C is put into hydrothermal reaction kettle and then hydrothermal reaction kettle is put into baking oven and heated, oven temperature is 180 ° C, the heat time is 8 ~ 16 hours, after completion of the reaction, reaction products therefrom is naturally cooled into room temperature, then washing 3 ~ 5 times, most Hydro-thermal reaction product is placed in 80 °C of baking oven is afterwards vacuum dried 24 hours, will be obtained after the grinding of dried product, screening Magnetic CoFe₂O₄Microparticle.

2nd, AgCl-BiOCl-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：5：10 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOCl of the AgCl of 5g and 10g are counted Calculate, the weight according to the AgCl for choosing obtains the mole of AgCl for 0.03484mol, then Ag moles divided by the molecular weight of AgCl It is 0.03484mol；Weight according to the BiOCl for choosing obtains molecular weight divided by BiOCl, and the mole for obtaining BiOCl is 0.03839mol, then the mole of Bi is 0.03839mol, needed for then the mole 0.03484mol according to Ag is calculated AgNO₃Weight be 5.918 grams, the mole 0.03839mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 18.622 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 5.918 grams of AgNO₃With 18.622 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.03839mol phases of the mole 0.03484mol and Bi of Ag that calculate Plus, the mole of the KCl needed for drawing is 0.07323mol, and the weight that the molar amount according to KCl calculates required KCl is 5.459g；

5.459 grams of KCl is weighed, is dissolved in the water of 50mL, then the KCl solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 40W and is irradiated and is stirred 5 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgCl, and it is 2% ~ 5% with the weight ratio of AgCl.

Embodiment three

CoFe₂O₄：AgCl：BiOCl=1：1：7, Ag is 2% ~ 3% with the weight ratio of AgCl.

First, magnetic corpuscular CoFe is prepared₂O₄

（1）, by the Co of 0.042 mol（NO₃）₂·6H₂O and 0.084mol Fe（NO₃）₃·9H₂O dissolves in the deionized water of 100mL In and uniform stirring, obtain the mixed solution A of cobalt nitrate and ferric nitrate；

2nd, AgCl-BiOCl-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：1：7 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOCl of the AgCl of 1g and 7g are counted Calculate, the weight according to the AgCl for choosing obtains the mole of AgCl for 0.00697mol, then Ag moles divided by the molecular weight of AgCl It is 0.00697mol；Weight according to the BiOCl for choosing obtains molecular weight divided by BiOCl, and the mole for obtaining BiOCl is 0.02687mol, then the mole of Bi is 0.02687mol, needed for then the mole 0.00697mol according to Ag is calculated AgNO₃Weight be 1.184 grams, the mole 0.02687mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 13.034 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 1.184 grams of AgNO₃With 13.034 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.02687mol phases of the mole 0.00697mol and Bi of Ag that calculate Plus, the mole of the KCl needed for drawing is 0.03384mol, and the weight that the molar amount according to KCl calculates required KCl is 2.523g；

2.523 grams of KCl is weighed, is dissolved in the water of 40mL, then the KCl solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 36W and is irradiated and is stirred 8 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgCl, and it is 2% ~ 3% with the weight ratio of AgCl.

Comparative example one

CoFe is used in the present embodiment₂O₄It is visible light catalyst, specific preparation method is as follows：

（4）, solution C is put into hydrothermal reaction kettle and carries out hydro-thermal reaction, hydrothermal temperature is 180 °C, the hydro-thermal reaction time It is 8 ~ 16 hours, after hydro-thermal reaction is finished, reaction products therefrom is naturally cooled into room temperature, then washes 3 ~ 5 times, finally by water Thermal response product is placed in 80 °C of baking oven and is vacuum dried 24 hours, magnetic will be obtained after the grinding of dried product, screening CoFe₂O₄Microparticle.

Comparative example two

BiOCl-CoFe is used in the present embodiment₂O₄It is visible light catalyst, CoFe₂O₄It is 1 with the weight ratio of BiOCl：4, specifically Preparation method is as follows：

Step one, preparation CoFe₂O₄

（1）, by the Co (NO of 0.042mol₃)₂·6H₂Fe (the NO of O and 0.084mol₃)₃·9H₂O dissolves in the deionized water of 100mL In and uniform stirring, obtain the mixed solution A of cobalt nitrate and ferric nitrate；

（2）, the NaOH of 0.34mol be dissolved in the deionized water of 100mL obtain solution B；

Step 2, preparation BiOCl-CoFe₂O₄

（1）, by 7.276 grams of Bi (NO₃)₃·5H₂O is uniformly stirred in being added to 200 mL and the aqueous solution containing 40 mL glacial acetic acid Mix, obtain bismuth nitrate solution under acid condition, this solution is designated as solution D；

（2）, by 1 gram of CoFe prepared in step one₂O₄Magnetic corpuscular is added in solution D, and in mechanical electric stirring Continuously stirred under device 30 minutes, this solution is designated as solution E；

（3）, weigh 1.118 grams of KCl, be dissolved in the water of 40mL, then the KCl solution is added drop-wise in solution E, drip Plus during be added dropwise while stirring, and continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution is obtained F。

（4）, product F washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in afterwards in 80 °C of baking oven and dry 24 hours, dried product grinding, screening obtained final product the cobalt ferrite BiOCl- CoFe of the oxygen of bismuth oxyiodide-four two₂O₄Magnetic visible ray Catalyst.

Comparative example three

AgCl-BiOCl-CoFe is used in the present embodiment₂O₄It is visible light catalyst, CoFe₂O₄, AgCl and BiOCl weight ratio It is 1：4：7, specific preparation method is as follows：

First, magnetic corpuscular CoFe is prepared₂O₄

（1）, by the Co (NO of 0.042 mol₃)₂·6H₂Fe (the NO of O and 0.084mol₃)₃·9H₂O dissolves in the deionization of 100mL In water and uniform stirring, the mixed solution A of cobalt nitrate and ferric nitrate is obtained；

2nd, magnetic photocatalyst AgCl-BiOCl-CoFe is prepared₂O₄

（1）By 1：4：7 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOCl of the AgCl of 4g and 7g are calculated, Weight according to the AgCl for choosing obtains the mole of AgCl for 0.02787mol divided by the molecular weight of AgCl, then Ag moles are 0.02787mol；Weight according to the BiOCl for choosing obtains molecular weight divided by BiOCl, and the mole for obtaining BiOCl is 0.02687mol, then the mole of Bi is 0.02687mol, needed for then the mole 0.02787mol according to Ag is calculated AgNO₃Weight be 4.734 grams, the mole 0.02687mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 13.034 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 4.734 grams of AgNO₃With 13.034 grams of Bi (NO₃)₃·5H₂O；

（2）The AgNO that will be weighed₃With Bi (NO₃)₃·5H₂During the volume ratio that O dissolves in 600mL is 20% glacial acetic acid aqueous solution, and Uniform stirring, obtains the mixed solution D of silver nitrate and bismuth nitrate under acid condition；

（3）, will in step one prepare 1 gram of magnetic CoFe₂O₄Microparticle is added in solution D, and is mixed 30 minutes, system Obtain solution E；

（4）, by above-mentioned steps（1）In the mole 0.02687mol phases of the mole 0.02787mol and Bi of Ag that calculate Plus, the mole of the KCl needed for drawing is 0.05474mol, and the weight that the molar amount according to KCl calculates required KCl is 4.08g；

4.08 grams of KCl is weighed, is dissolved in the water of 40mL, then the KCl solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

（5）, aaerosol solution F washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in afterwards in 80 °C of baking oven Dry 24 hours, dried product grinding, screening obtain final product AgCl-BiOCl-CoFe₂O₄Magnetic photocatalyst.

As shown in figure 1, using the magnetic photocatalyst in embodiment one, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment one is to cigarette The removal efficiency of Elemental Mercury is about 85% in gas.

As shown in figure 1, using the magnetic photocatalyst in embodiment two, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment two is to cigarette The removal efficiency of Elemental Mercury is about 88% in gas.

As shown in figure 1, using the magnetic photocatalyst in embodiment three, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment three is to cigarette The removal efficiency of Elemental Mercury is about 92% in gas.

As shown in figure 1, using the visible light catalyst CoFe in comparative example one₂O₄, using in wet method removing flue gas Elemental Mercury Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic visible ray The consumption of catalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, it is seen that photochemical catalyst CoFe₂O₄To in flue gas The removal efficiency of Elemental Mercury is about 5%.

As shown in figure 1, using the magnetic photocatalyst BiOCl-CoFe in comparative example two₂O₄, removed using wet method The Elemental Mercury Hg gone in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, The consumption of magnetic photocatalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, magnetic photocatalyst BiOCl-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 35%.

As shown in figure 1, using the magnetic photocatalyst AgCl-BiOCl- CoFe in comparative example three₂O₄, utilize Wet method removes the Elemental Mercury Hg in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/ m³Under, the consumption of magnetic photocatalyst is 0.1 g/L, and reaction temperature is under the conditions of 45 °C, through statistics, magnetic visible ray Catalyst AgCl-BiOCl-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 65%.

In sum, magnetic photocatalyst Ag-AgCl-BiOCl-CoFe of the invention₂O₄Flue gas can be greatly improved In Elemental Mercury removal efficiency.

Example IV

A kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, by Ag, AgBr, BiOBr and CoFe₂O₄Composition, CoFe₂O₄, AgBr and BiOBr weight ratio be：

CoFe₂O₄：AgBr：BiOBr=1：1：1, Ag is 1% ~ 2% with the weight ratio of AgBr.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgBr-BiOBr-CoFe is prepared₂O₄Magnetic suspension solution

（1）By 1：1：1 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOBr of the AgBr of 1g and 1g are calculated, Weight according to the AgBr for choosing obtains the mole of AgBr for 0.00535mol divided by the molecular weight of AgBr, then Ag moles are 0.00535mol；Weight according to the BiOBr for choosing obtains molecular weight divided by BiOBr, and the mole for obtaining BiOBr is 0.00329mol, then the mole of Bi is 0.00329mol, needed for then the mole 0.00535mol according to Ag is calculated AgNO₃Weight be 0.9088 gram, the mole 0.00329mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 1.5959 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 0.9088 gram of AgNO₃With 1.5959 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.00329mol phases of the mole 0.00535mol and Bi of Ag that calculate Plus, the mole of the KBr needed for drawing is 0.00864mol, and the weight that the molar amount according to KBr calculates required KBr is 1.0282g；

1.0282 grams of KBr is weighed, is dissolved in the water of 30mL, then the KBr solution is added drop-wise in solution E, be added dropwise During be added dropwise while stirring, and continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 36W and is irradiated and is stirred 2.5 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgBr, and it is 1% ~ 2% with the weight ratio of AgBr.

Embodiment five

CoFe₂O₄：AgBr：BiOBr=1：10：20, Ag is 2% ~ 5% with the weight ratio of AgBr.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgBr-BiOBr-CoFe is prepared₂O₄Magnetic suspension solution

（1）By 1：10：20 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOBr of the AgBr of 10g and 20g are carried out Calculate, the weight according to the AgBr for choosing obtains the mole of AgBr for 0.05347mol divided by the molecular weight of AgBr, then Ag moles It is 0.05347mol to measure；Weight according to the BiOBr for choosing obtains molecular weight divided by BiOBr, and the mole for obtaining BiOBr is 0.06579mol, then the mole of Bi is 0.06579mol, needed for then the mole 0.05347mol according to Ag is calculated AgNO₃Weight be 9.0829 grams, the mole 0.06579mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 31.9128 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 9.0829 grams of AgNO₃With 31.9128 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.06579mol phases of the mole 0.05347mol and Bi of Ag that calculate Plus, the mole of the KBr needed for drawing is 0.11926mol, and the weight that the molar amount according to KBr calculates required KBr is 14.192g；

14.192 grams of KBr is weighed, is dissolved in the water of 100mL, then the KBr solution is added drop-wise in solution E, be added dropwise During be added dropwise while stirring, and continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 40W and is irradiated and is stirred 4 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgBr, and it is 2% ~ 5% with the weight ratio of AgBr.

Embodiment six

CoFe₂O₄：AgBr：BiOBr=1：2：4, Ag is 2% ~ 3% with the weight ratio of AgBr.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgBr-BiOBr-CoFe is prepared₂O₄Magnetic suspension solution

（1）By 1：2：4 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOBr of the AgBr of 2g and 4g are calculated, Weight according to the AgBr for choosing obtains the mole of AgBr for 0.01069mol divided by the molecular weight of AgBr, then Ag moles are 0.01069mol；Weight according to the BiOBr for choosing obtains molecular weight divided by BiOBr, and the mole for obtaining BiOBr is 0.01316mol, then the mole of Bi is 0.01316mol, needed for then the mole 0.01069mol according to Ag is calculated AgNO₃Weight be 1.8159 grams, the mole 0.01316mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 6.3835 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 1.8159 grams of AgNO₃With 6.3835 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.01316mol phases of the mole 0.01069mol and Bi of Ag that calculate Plus, the mole of the KBr needed for drawing is 0.02385mol, and the weight that the molar amount according to KBr calculates required KBr is 2.838g；

2.838 grams of KBr is weighed, is dissolved in the water of 50mL, then the KBr solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is prepared₂O₄

（1）, aaerosol solution F is placed under the ultraviolet lamp of 36W and is irradiated and is stirred 3 hours；

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe is obtained₂O₄。 Ag in the magnetic photocatalyst is shown in that light decomposes gained by AgBr, and it is 2% ~ 3% with the weight ratio of AgBr.

Comparative example four

BiOBr-CoFe is used in the present embodiment₂O₄It is visible light catalyst, CoFe₂O₄It is 1 with the weight ratio of BiOBr：4, specifically Preparation method is as follows：

Step one, preparation CoFe₂O₄

Step 2, preparation BiOBr-CoFe₂O₄

（1）, by 0.013mol Bi (NO₃)₃·5H₂O is uniformly stirred in being added to 200mL and the aqueous solution containing 35 mL glacial acetic acid Mix, obtain bismuth nitrate solution under acid condition, this solution is designated as solution D；

（2）, by 0.043mol CoFe prepared in step₂O₄Magnetic corpuscular is added in solution A, and electronic in machinery Continuously stirred under agitator 30 minutes, this solution is designated as solution E；

（3）, under mechanical electric stirring 0.013mol KBr are dropwise added into solution E continuously stir 2 hours after stand 12 again Hour, products therefrom is designated as F；

（4）, product C washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in 70 °C of baking oven that to dry 24 small afterwards When, dried product grinding, screening obtain final product the cobalt ferrite BiOBr-CoFe of the oxygen of bismuth oxybromide-four two₂O₄Magnetic visible light catalytic Agent.

Comparative example five

AgBr-BiOBr-CoFe is used in the present embodiment₂O₄It is visible light catalyst, wherein CoFe₂O₄, AgBr and BiOBr weight Amount is than being 1：3：11, specific preparation method is as follows：

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, magnetic photocatalyst AgBr-BiOBr-CoFe is prepared₂O₄

（1）By 1：3：11 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOBr of the AgBr of 3g and 11g are counted Calculate, the weight according to the AgBr for choosing obtains the mole of AgBr for 0.01604mol, then Ag moles divided by the molecular weight of AgBr It is 0.01604mol；Weight according to the BiOBr for choosing obtains molecular weight divided by BiOBr, and the mole for obtaining BiOBr is 0.03618mol, then the mole of Bi is 0.03618mol, needed for then the mole 0.01604mol according to Ag is calculated AgNO₃Weight be 2.7247 grams, the mole 0.03618mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O It is 17.5498 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 2.7247 grams of AgNO₃With 17.5498 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.03618mol phases of the mole 0.01604mol and Bi of Ag that calculate Plus, the mole of the KBr needed for drawing is 0.05222mol, and the weight that the molar amount according to KBr calculates required KBr is 6.214g；

6.214 grams of KBr is weighed, is dissolved in the water of 80mL, then the KBr solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

（5）, aaerosol solution F washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in afterwards in 80 °C of baking oven Dry 24 hours, dried product grinding, screening obtain final product AgBr-BiOBr-CoFe₂O₄Magnetic photocatalyst.

As shown in Fig. 2 using the magnetic photocatalyst in example IV, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in example IV is to cigarette The removal efficiency of Elemental Mercury is about 86% in gas.

As shown in Fig. 2 using the magnetic photocatalyst in embodiment five, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment five is to cigarette The removal efficiency of Elemental Mercury is about 90% in gas.

As shown in Fig. 2 using the magnetic photocatalyst in embodiment six, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment six is to cigarette The removal efficiency of Elemental Mercury is about 95% in gas.

As shown in Fig. 2 using the visible light catalyst CoFe in comparative example one₂O₄, using in wet method removing flue gas Elemental Mercury Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic visible ray The consumption of catalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, it is seen that photochemical catalyst CoFe₂O₄To in flue gas The removal efficiency of Elemental Mercury is about 5%.

As shown in Fig. 2 using the magnetic photocatalyst BiOBr-CoFe in comparative example four₂O₄, removed using wet method The Elemental Mercury Hg gone in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, The consumption of magnetic photocatalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, magnetic photocatalyst BiOBr-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 40%.

As shown in Fig. 2 using the magnetic photocatalyst AgBr-BiOBr-CoFe in comparative example five₂O₄, utilize Wet method removes the Elemental Mercury Hg in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/ m³Under, the consumption of magnetic photocatalyst is 0.1 g/L, and reaction temperature is under the conditions of 45 °C, through statistics, magnetic visible ray Catalyst AgBr-BiOBr-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 75%.

In sum, magnetic photocatalyst Ag-AgBr-BiOBr-CoFe of the invention₂O₄Flue gas can be greatly improved In Elemental Mercury removal efficiency.

Embodiment seven

A kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, wherein：By Ag, AgI, BiOI and CoFe₂O₄Composition, CoFe₂O₄, AgI and BiOI weight ratio be：

CoFe₂O₄：AgI：BiOI=1：1：1, Ag is 0.1% ~ 2% with the weight ratio of AgI.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgI-BiOI-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：1：1 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOI of the AgI of 1g and 1g are calculated, Weight according to the AgI for choosing obtains the mole of AgI for 0.00426mol divided by the molecular weight of AgI, then Ag moles are 0.00426mol obtains molecular weight according to the weight of the BiOI for choosing divided by BiOI, obtains the mole of BiOI for 0.00284mol, then The mole of Bi is 0.00284mol, and then the mole 0.00426mol mol according to Ag calculate required AgNO₃Weight It is 0.7236 gram to measure, and the mole 0.00284mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O is 1.3776 Gram；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 0.7236 gram of AgNO₃With 1.3776 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.00284mol phases of the mole 0.00426mol and Bi of Ag that calculate Plus, the mole of the KI needed for drawing is 0.0074mol, and the weight that the molar amount according to KI calculates required KI is 1.1786g；

1.1786 grams of KI is weighed, is dissolved in the water of 20mL, then the KI solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgI-BiOI-CoFe is prepared₂O₄

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgI-BiOI-CoFe is obtained₂O₄.Should Ag in magnetic photocatalyst is shown in that light decomposes gained by AgI, and it is 0.1% ~ 2% with the weight ratio of AgI.

Embodiment eight

CoFe₂O₄：AgI：BiOI=1：10：10, Ag is 2% ~ 4% with the weight ratio of AgI.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgI-BiOI-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：10：10 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOI of the AgI of 10g and 10g are counted Calculate, the weight according to the AgI for choosing obtains the mole of AgI for 0.04259mol divided by the molecular weight of AgI, then Ag moles are 0.04259mol obtains molecular weight according to the weight of the BiOI for choosing divided by BiOI, obtains the mole of BiOI for 0.02842mol, then The mole of Bi is 0.02842mol, and then the mole 0.04259mol mol according to Ag calculate required AgNO₃Weight It is 7.235 grams to measure, and the mole 0.02842mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O is 13.786 Gram；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 7.235 grams of AgNO₃With 13.786 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.02842mol phases of the mole 0.04259mol and Bi of Ag that calculate Plus, the mole of the KI needed for drawing is 0.07101mol, and the weight that the molar amount according to KI calculates required KI is 11.787g；

11.787 grams of KI is weighed, is dissolved in the water of 100mL, then the KI solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgI-BiOI-CoFe is prepared₂O₄

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgI-BiOI-CoFe is obtained₂O₄.Should Ag in magnetic photocatalyst is shown in that light decomposes gained by AgI, and it is 2% ~ 4% with the weight ratio of AgI.

Embodiment nine

A kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, by Ag, AgI, BiOI and CoFe₂O₄ Composition, CoFe₂O₄, AgI and BiOI weight ratio be：

CoFe₂O₄：AgI：BiOI=1：1.5：2.5, Ag is 2 ~ 3% with the weight ratio of AgI.

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, AgI-BiOI-CoFe is prepared₂O₄Magnetic suspension solution

（1）, by 1：1.5：2.5 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOI of the AgI of 1.5g and 2.5g enter Row is calculated, and the weight according to the AgI for choosing obtains the mole of AgI for 0.00639mol divided by the molecular weight of AgI, then Ag moles Measure as 0.00639mol obtains molecular weight according to the weight of the BiOI for choosing divided by BiOI, obtain the mole of BiOI for 0.0071mol, Then the mole of Bi is 0.0071mol, and then the mole 0.00639mol according to Ag calculates required AgNO₃Weight It it is 1.0855 grams, the mole 0.0071mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O is 3.4439 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 1.0855 grams of AgNO₃With 3.4439 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.0071mol of the mole 0.00639mol and Bi of Ag that calculates be added, The mole of the KI needed for drawing is 0.01349mol, and the weight that the molar amount according to KI calculates required KI is 2.239g；

2.239 grams of KI is weighed, is dissolved in the water of 100mL, then the KI solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

3rd, magnetic photocatalyst Ag-AgI-BiOI-CoFe is prepared₂O₄

（3）, with ethanol solution cyclic washing sediment 3 ~ 5 times, be vacuum dried 24 in the baking oven that 80 °C are put the precipitate in afterwards Hour, finally by the grinding of dried sediment, screening, magnetic photocatalyst Ag-AgI-BiOI-CoFe is obtained₂O₄.Should Ag in magnetic photocatalyst is shown in that light decomposes gained by AgI, and it is 2% ~ 3% with the weight ratio of AgI.

Comparative example six：

The present embodiment kind uses BiOI-CoFe₂O₄It is visible light catalyst, wherein CoFe₂O₄It is 1 with the weight ratio of BiOI：4, tool Preparation is as follows：

Step one, preparation CoFe₂O₄

Step 2, preparation BiOI-CoFe₂O₄

（1）, by 0.0114mol Bi (NO₃)₃·5H₂O is added in 200 mL and the aqueous solution containing 40 mL glacial acetic acid uniform Stirring, obtains bismuth nitrate solution under acid condition, and this solution is designated as solution D；

（2）, by 0.0043mol CoFe prepared in step one₂O₄Magnetic corpuscular is added in solution D, and in mechanical electric Continuously stirred 30 minutes under dynamic agitator, this solution is designated as solution E；

（3）, under mechanical electric stirring 0.0114 mol KI are dropwise added into solution E continuously stir 2 hours after stand 12 again Hour, products therefrom is designated as F；

（4）, product F washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in 80 °C of baking oven that to dry 24 small afterwards When, dried product grinding, screening obtain final product the cobalt ferrite BiOI- CoFe of the oxygen of bismuth oxyiodide-four two₂O₄Magnetic visible light catalytic Agent.

Comparative example seven：

The present embodiment kind uses AgI-BiOI-CoFe₂O₄It is magnetic photocatalyst, wherein CoFe₂O₄, AgI and BiOI weight Amount is than being 1：2：8, specific preparation method is as follows：

First, magnetic corpuscular CoFe is prepared₂O₄

2nd, magnetic photocatalyst AgI-BiOI- CoFe are prepared₂O₄

（1）, by 1：2：8 weight ratio, chooses the magnetic CoFe of 1g₂O₄Microparticle, the BiOI of the AgI of 2g and 8g are calculated, Weight according to the AgI for choosing obtains the mole of AgI for 0.00852mol divided by the molecular weight of AgI, then Ag moles are 0.00852mol, the weight according to the BiOI for choosing obtains molecular weight divided by BiOI, obtains the mole of BiOI for 0.02274mol, then The mole of Bi is 0.02274mol, and then the mole 0.00852mol according to Ag calculates required AgNO₃Weight be 1.4473 grams, the mole 0.02274mol according to Bi calculates required Bi (NO₃)₃·5H₂The weight of O is 11.0305 grams；

Weigh the 1 gram of magnetic CoFe prepared in step one₂O₄Microparticle, weighs 1.4473 grams of AgNO₃With 11.0305 grams of Bi (NO₃)₃·5H₂O；

（4）, by above-mentioned steps（1）In the mole 0.02274mol phases of the mole 0.00852mol and Bi of Ag that calculate Plus, the mole of the KI needed for drawing is 0.03126mol, and the Molecular weights that the mole of KI is multiplied by KI are calculated into required KI's Weight is 5.189g；

5.189 grams of KI is weighed, is dissolved in the water of 100mL, then the KI solution is added drop-wise in solution E, be added dropwise It is added dropwise while stirring in journey, and is continuously stirred after completion of dropping 2 hours, stand 12 hours again afterwards, aaerosol solution F is obtained.

（5）, aaerosol solution F washed 3 ~ 5 times with the mixed liquor of deionized water and ethanol, be placed in afterwards in 80 °C of baking oven Dry 24 hours, dried product grinding, screening obtain final product AgI-BiOI-CoFe₂O₄Magnetic photocatalyst.

As shown in figure 3, using the magnetic photocatalyst in embodiment seven, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment seven is to cigarette The removal efficiency of Elemental Mercury is about 93% in gas.

As shown in figure 3, using the magnetic photocatalyst in embodiment seven, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment eight is to cigarette The removal efficiency of Elemental Mercury is about 96% in gas.

As shown in figure 3, using the magnetic photocatalyst in embodiment seven, the Elemental Mercury in flue gas is removed using wet method Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic photocatalyst Consumption be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, the magnetic photocatalyst in embodiment nine is to cigarette The removal efficiency of Elemental Mercury is about 99% in gas.

As shown in figure 3, using the visible light catalyst CoFe in comparative example one₂O₄, using in wet method removing flue gas Elemental Mercury Hg⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, magnetic visible ray The consumption of catalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, it is seen that photochemical catalyst CoFe₂O₄To in flue gas The removal efficiency of Elemental Mercury is about 5%.

As shown in figure 3, using the magnetic photocatalyst BiOI-CoFe in comparative example six₂O₄, removed using wet method The Elemental Mercury Hg gone in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³Under, The consumption of magnetic photocatalyst be 0.1 g/L, reaction temperature be 45 °C under the conditions of, through statistics, magnetic photocatalyst BiOI-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 60%.

As shown in figure 3, using the magnetic photocatalyst AgI-BiOI-CoFe in comparative example seven₂O₄, using wet Method removes the Elemental Mercury Hg in flue gas⁰, flue gas main component is N₂、O₂、CO₂, Elemental Mercury Hg in flue gas⁰Concentration be 50 μ g/m³ Under, the consumption of magnetic photocatalyst is 0.1 g/L, and reaction temperature is under the conditions of 45 °C, through statistics, magnetic visible ray is urged Agent AgI-BiOI-CoFe₂O₄Removal efficiency to Elemental Mercury in flue gas is about 88%.

In sum, magnetic photocatalyst Ag-AgI-BiOI-CoFe of the invention₂O₄In can greatly improving flue gas Elemental Mercury removal efficiency.

It is noted that embodiment described above is to the illustrative and not limiting of technical solution of the present invention, affiliated technology neck The equivalent of domain those of ordinary skill or other modifications made according to prior art, as long as not exceeding the technology of the present invention side The thinking and scope of case, should be included within interest field of the presently claimed invention.

Claims

1. a kind of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite, it is characterised in that：By Ag, AgX（X =Cl、Br、I）、BiOX（X=Cl、Br、I）And CoFe₂O₄Composition.

2. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgI, BiOI and CoFe₂O₄Composition, CoFe₂O₄, AgI and BiOI weight ratio be CoFe₂O₄：AgI：BiOI=1：（1~10）：（1~10）, the weight ratio of Ag and AgI is 0.1% ~ 10%.

3. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgI, BiOI and CoFe₂O₄Composition, CoFe₂O₄, AgI and BiOI weight ratio be CoFe₂O₄：AgI：BiOI=1： 1.5：2.5, Ag is 1 ~ 5% with the weight ratio of AgI.

4. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgCl, BiOCl and CoFe₂O₄Composition, CoFe₂O₄, AgCl and BiOCl weight ratio be CoFe₂O₄：AgCl： BiOCl=1：（1~5）：（1~10）, the weight ratio of Ag and AgCl is 0.1% ~ 10%.

5. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgCl, BiOCl and CoFe₂O₄Composition, CoFe₂O₄, AgCl and BiOCl weight ratio be CoFe₂O₄：AgCl： BiOCl=1：1：7, Ag is 1 ~ 5% with the weight ratio of AgCl.

6. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgBr, BiOBr and CoFe₂O₄Composition, CoFe₂O₄, AgBr and BiOBr weight ratio be CoFe₂O₄：AgBr： BiOBr=1：（1~10）：（1~20）, the weight ratio of Ag and AgBr is 0.1% ~ 10%.

7. composite magnetic visible light catalyst silver according to claim 1-silver halide-BiOX-cobalt ferrite, its feature It is：By Ag, AgBr, BiOBr and CoFe₂O₄Composition, CoFe₂O₄, AgBr and BiOBr weight ratio be CoFe₂O₄：AgBr： BiOBr=1：2：4, Ag is 1 ~ 5% with the weight ratio of AgBr.

8. the composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite as described in any one of claim 1 ~ 7 Preparation method, it is characterised in that：Comprise the technical steps that：

First, magnetic corpuscular CoFe is prepared₂O₄

9. the preparation of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite according to claim 8 Method, it is characterised in that：Step one（4）It is middle that solution C is put into hydrothermal reaction kettle, then hydrothermal reaction kettle is put into baking oven Heating, oven temperature is 150 ~ 200 °C, and the heat time is 8 ~ 16 hours.

10. the preparation of composite magnetic visible light catalyst silver-silver halide-BiOX-cobalt ferrite according to claim 8 Method, it is characterised in that：Step 2（1）In, the volume fraction of glacial acetic acid is 10% ~ 50% in the aqueous solution of described glacial acetic acid.