A kind of method that removes trace mercury in water solution
[technical field]
The present invention relates to the field of waste water treatment in environment, particularly a kind of method that removes trace mercury in water solution.
[background technology]
Along with increasing sharply of trade waste, the heavy metal in water mercury pollution causing is more and more serious.In trade effluent, usually find mercury, maximum mercury pollution source is from industries such as metallurgy, chemical industry, agricultural chemicals, pigment, fuel, papermaking, process hides.In these industrial effluent liquid, usually contain the poisonous mercuride of a great deal of.
Traditional method that removes mercury is suitable for processing the waste liquid that mercury content is higher, but removal effect is undesirable for the lower liquid waste disposal of mercury content, and produces a large amount of waste residues, but also may in water body, introduce undesirable ion.
[summary of the invention]
The object of the invention is for protection of the environment, meet the needs of economical and efficient simultaneously, and a kind of method that removes micro-Trace Hg in the aqueous solution is provided.The method comprises the pH value that regulates pending mercurous waste liquid with acid or alkali, adds title complex or the mixture of S-contained substance and copper, zinc or iron, through standing, after precipitation, isolates mercurous precipitation.
The invention discloses a kind of method that removes trace mercury in water solution, it is characterized in that: in the pending aqueous solution that contains mercury, add S-contained substance and contain zincon, contain α-benzoinoxime or contain one or more title complexs that form on the spot or the mixture in ferron, or add S-contained substance with containing zincon, containing α-benzoinoxime or containing title complex or the mixture of one or more formation in ferron, with acid or alkali, regulate the pH value 5-8 of the pending aqueous solution, then standing solution, separates out precipitation; Finally separate mercurous precipitation.
Also can be before aforesaid method operation, first the described pending mercurous aqueous solution is added to one or both in phosphoric acid salt and calcium salt or magnesium salts under violent stirring, then filter or centrifugation goes out mercurous precipitation.Or carry out with aforesaid method simultaneously.
The pending aqueous temperature of described method treating processes is 10-150 ℃, and the pending aqueous solution pH of described method treating processes is 5-8.
Said S-contained substance is Gelucystine, halfcystine, dimercaptosuccinic acid or DMSA, or two or more mixture in them.The consumption of said sulfur-bearing regent is that the mol ratio of sulphur and mercury is 1-50:1.
Said is zinc chloride containing zincon source, zinc phosphate, zinc nitrate, zinc sulfate, zinc carbonate, zinc acetate, zinc sulphide or zinc hydroxide, or two or more mixture in them.The consumption in described zinc source is that the mol ratio of zinc and sulphur is 1-5:1.
Said cupric reagent source is cupric nitrate, copper sulfate, cupric chloride, cupric sulfide, copper hydroxide, copper carbonate, neutralized verdigris or cupric oxalate, or two or more mixture in them.Or their mixture; The consumption in described copper source is that the mol ratio of copper and sulphur is 1-5:1.
Said iron content reagent source is iron trichloride, iron protochloride, iron nitrate, ferric sulfate, ferrous sulfate, iron carbonate, iron protocarbonate, iron acetate, Iron diacetate, Iron sulfuret or ironic hydroxide, or two or more mixture in them.The consumption of described source of iron is that the mol ratio of iron and sulphur is 1-6:1.
Described calcium salt is calcium chloride, nitrocalcite, and calcium phosphate, calcium sulfate, the mixture of one or more in caoxalate or calcium acetate, the mol ratio that described calcium salt consumption is calcium and mercury is 1-50:1.
Described magnesium salts is magnesium chloride, magnesium nitrate, and trimagnesium phosphate, magnesium sulfate, the mixture of one or more in magnesium oxalate or magnesium acetate, the mol ratio that described magnesium salts consumption is magnesium and mercury is 1-50:1.
Described phosphoric acid salt is sodium phosphate, SODIUM PHOSPHATE, MONOBASIC, Sodium phosphate dibasic, ammonium phosphate, primary ammonium phosphate, ammonium hydrogen phosphate, calcium phosphate, or one or more the mixture in trimagnesium phosphate.The mol ratio that described phosphoric acid salt consumption is phosphorus and mercury is 1-50:1.
The present invention has developed a kind of method that removes trace mercury in water solution, can be used for administering trade effluent.This method is taken into account economy and environment protection simultaneously.It can cut the waste, and improves the decreasing ratio of Low Concentration Mercury, reduces costs, and reduces environmental pollution simultaneously.
Feature of the present invention is by cultivation and anatomy to growing plant under mercury environment, utilize co-precipitation principle, by controlling pH, and sulfur-bearing regent and the title complex of zinc, copper or iron or the add-on of mixture, substantially remove the mercury in mercurous waste liquid completely.The raw materials used economy of the present invention is easy to get, and reagent dosage is few, and waste residue generation is few.In the aqueous solution after treatment, mercury content is less than 0.01mg/L, can enter secondary network.Therefore be a kind of environmentally friendly treatment process.This technique can be widely used in the processing of the mercury-containing waste water discharging in the fields such as metallurgy, chemical industry, agricultural chemicals, pigment, fuel, papermaking, process hides.
[embodiment]
Embodiment 1: take 0.5 g Cys, add 50 mL water to dissolve completely to it.Take in addition 1.0g nitrate trihydrate copper or 1.0g cupric sulfate pentahydrate, add 20mL water that it is dissolved completely.Then under violent stirring and room temperature, this copper solutions is dropwise joined in Cys solution.Treat that copper solutions dropwises, continue reaction 1 hour.Afterwards, filtration or centrifugation, the dry mixture that obtains yellowish green Cys and copper.Measuring mercury content is the aqueous solution 50 mL of 5 mg/L, regulates pH to 6-7, adds Cys that 0.1 g obtains and the mixture of copper, exchanges 24 h under room temperature, and interrupted oscillation fully acts on it during this time.Afterwards, standing, sedimentation also removes by filter mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 2: measuring mercury content is the aqueous solution 100 mL of 5 mg/L, the pH 5-6 of regulator solution.Under violent stirring, add 0.1g dimercaptosuccinic acid, 0.1 g tri-water cupric oxalates and 0.2g iron vitriol.Controlling pH value of solution 7-8(can add sodium hydroxide or hydrochloric acid to regulate), under room temperature, continue to stir 2 hours.Afterwards, standing 24 hours, sedimentation was also centrifugally removed mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 3: put into 0.6g dimercaptosuccinic acid and 0.9g zinc nitrate hexahydrate or 0.4g zinc chloride in reactor, react 24 h at 120~140 ℃.Afterwards, standing cooling, filtration or centrifugation are precipitated product.This product is through energy spectrum analysis: this product is through energy spectrum analysis: S:Zn=1:1(mol ratio), shown to obtain title complex or the mixture of a sulfur-bearing regent and zinc.The product that 0.1g is obtained joins in the aqueous solution that 50mL mercury content is 2 mg/L, the pH 6-7 of regulator solution, and to control aqueous temperature be 45 ℃.Continue to stir 2 hours.Afterwards, standing, sedimentation also removes by filter mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 4: measuring mercury content is the aqueous solution 100 mL of 5 mg/L, controlling aqueous temperature is 40 ℃.Under the condition of violent stirring hierarchy of control pH 7-8, (while needing, with sodium hydroxide or hydrochloric acid, regulate), add 0.1g Gelucystine and 0.1g zinc sulphide, continue to stir 2 hours.Afterwards, standing, sedimentation is also centrifugally removed mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 5: measuring mercury content is the aqueous solution 250 mL of 50 mg/L, controlling aqueous temperature is 80 ℃.Under the condition of violent stirring hierarchy of control pH 7-8, (while needing, with sodium hydroxide or hydrochloric acid, regulate), add 0.2 g four water-calcium nitrate, 0.2 g magnesium acetate and 50 mg Sodium phosphate dibasics.Continue to stir 2 hours.Afterwards, standing, sedimentation also removes by filter mercurous throw out.In filtrate, add the Cys that obtains in 0.1g embodiment 1 and the mixture of copper, absorption 24h, interrupted oscillation fully acts on it during this time.Afterwards, standing, sedimentation also removes by filter mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 6: measuring mercury content is the aqueous solution 250 mL of 50 mg/L, controlling aqueous temperature is 30 ℃.Under the condition of violent stirring hierarchy of control pH 6-7, add 0.1 g calcium phosphate and 0.1g trimagnesium phosphate.Continue to stir 2 hours.Afterwards, standing, sedimentation also removes by filter mercurous throw out.In filtrate, add the Cys that obtains in 0.1 gram of embodiment 3 and the mixture of zinc, absorption 24h, interrupted oscillation fully acts on it during this time.Afterwards, standing, sedimentation also removes by filter mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 7: measuring mercury content is the aqueous solution 50 mL of 5 mg/L, controlling aqueous temperature is 20 ℃.Under the condition of violent stirring hierarchy of control pH 5-6, (while needing, with sodium hydroxide or hydrochloric acid, regulate), add 0.1g Gelucystine and 0.1g ironic hydroxide, continue to stir 2 hours.Afterwards, standing 24 hours, sedimentation was also centrifugally removed mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.
Embodiment 8: measuring mercury content is the aqueous solution 100 mL of 50 mg/L, controlling aqueous temperature is 20 ℃.Under the condition of violent stirring hierarchy of control pH 5-6, (while needing, with sodium hydroxide or hydrochloric acid, regulate), add 0.1 g caoxalate, 50 m g Cys and 0.1 g copper carbonate, continue to stir 2 hours.Afterwards, standing 24 hours, sedimentation was also centrifugally removed mercurous throw out.Mercury content through icp analysis filtrate is less than 0.01mg/L.