CN103880024B - A kind of preparation method of large pore volume silica-gel carrier - Google Patents
A kind of preparation method of large pore volume silica-gel carrier Download PDFInfo
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- CN103880024B CN103880024B CN201210563343.XA CN201210563343A CN103880024B CN 103880024 B CN103880024 B CN 103880024B CN 201210563343 A CN201210563343 A CN 201210563343A CN 103880024 B CN103880024 B CN 103880024B
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Abstract
The present invention proposes a kind of preparation method of large pore volume silica-gel carrier, there is pore volume, aperture problem less than normal for solving existing silica-gel carrier.The preparation method of large pore volume silica-gel carrier comprises: hydrolysis silicon source, auxiliary agent and deionized water are mixed and sedimentation and filtration according to preset ratio, generates silicon hydrating solution for subsequent use; The mineral acid being diluted to preset concentration is mixed with silicon hydrating solution and generates silicic acid sol; Regulate the pH value of silicic acid sol to producing silicic acid gel; On a preset condition based silicic acid gel grain is generated to the silicic acid gel ageing that adds water, and wash-out filtration is carried out to silicic acid gel grain, obtain wash-out filter after silicic acid gel grain; On a preset condition based, the silicic acid gel grain after being filtered by wash-out dries calcination, obtains large pore volume silica-gel carrier.The silica-gel carrier pore volume that the preparation method of large pore volume silica-gel carrier of the present invention obtains can at 2.0 ~ 3.5ml/g or larger, and bulk specific gravity is less than 300g/L, and aperture is greater than 40nm.
Description
Technical field
The present invention relates to biological medicine and catalysis technical field, refer to a kind of preparation method of large pore volume silica-gel carrier especially.
Background technology
Silica gel has special pore structure, large specific surface area and excellent thermostability, is widely used in each industrial circles such as sorbent material, siccative, thickening material, matting agent, battery electron material and support of the catalyst.In recent years, polythene material has become the requisite part of national economy, and obtains swift and violent development, and poly production method has vapor phase process, slurry process and solution method three productions technique
At present in gas phase polymerization polyethylene catalysts preparation process, silica gel is widely used as a kind of carrier.The catalyzer utilizing this carrier to make is mainly used in LLDPE(LinearLow-DensityPolyethy – lene, LLDPE) production.The silica-gel carrier of current use, its pore property is: pore volume 1.6ml/g, specific surface area 300 ~ 350m
2/ g, mean particle size 40 ~ 50 μm.The catalyst activity utilizing this carrier to prepare can only reach 3000 ~ 4000gPE/gcat, poly production cost is made to remain high like this, external current research shows, utilize large pore volume, catalyst activity prepared by bigger serface special silica-gel carrier can reach 6000 ~ 7000gPE/gcat, can make production equipment when constant, make production efficiency increase substantially like this, production cost is reduced further, the pore property of this carrier is: pore volume 2.4 ~ 2.8ml/g, specific surface area 500 ~ 600m
2/ g, mean particle size 50 ~ 150 μm.But, still there is pore volume in this carrier, aperture is less than normal, macromole is not easily adsorbed or is separated, the shortcoming that specific surface area is less than normal, thus part industry, medicine purify and the field such as chromatogram substitute by macroporous resin product, because it has the irreplaceable physical properties of macroporous resin, make it be subject to certain attention in the exploitation of some Application Areas and new technologies and materials, therefore the development of product of the present invention to novel material new technology has special meaning.
Summary of the invention
The present invention proposes a kind of preparation method of large pore volume silica-gel carrier, solves silica-gel carrier in prior art and there is pore volume, aperture problem less than normal.
Technical scheme of the present invention is achieved in that
A preparation method for large pore volume silica-gel carrier, comprises the following steps:
Hydrolysis silicon source, auxiliary agent and deionized water are mixed and sedimentation and filtration according to preset ratio, generates silicon hydrating solution for subsequent use;
The mineral acid being diluted to preset concentration is mixed with described silicon hydrating solution and generates silicic acid sol;
Regulate the pH value of described silicic acid sol to producing silicic acid gel;
On a preset condition based silicic acid gel grain is generated to the ageing that adds water of described silicic acid gel, and wash-out filtration is carried out to described silicic acid gel grain, obtain wash-out filter after silicic acid gel grain;
On a preset condition based, the silicic acid gel grain after being filtered by described wash-out dries calcination, obtains large pore volume silica-gel carrier.
Further, describedly hydrolysis silicon source, auxiliary agent and deionized water to be mixed and sedimentation and filtration according to preset ratio, the step generating silicon hydrating solution for subsequent use is specially:
Hydrolysis silicon source, auxiliary agent and deionized water is even according to the mixed in molar ratio of 45 ~ 80:0.05 ~ 2:20 ~ 50, at 15 DEG C ~ 35 DEG C temperature, be mixed with the solution of 12 ~ 30 degree Beaume, generate silicon hydrating solution after sedimentation and filtration for subsequent use.
Preferably, described hydrolysis silicon source be in water glass, tetraethoxy, TMOS any one or multiple.
Further, describedly the mineral acid being diluted to preset concentration mixed with described silicon hydrating solution the step generating silicic acid sol be specially:
Mineral acid being diluted to concentration is 3.02mol/L ~ 21.38mol/L;
Described silicon hydrating solution being added described concentration is carry out mixing in the mineral acid of 3.02mol/L ~ 21.38mol/L to generate silicic acid sol.
Further, describedly on a preset condition based silicic acid gel grain is generated to the ageing that adds water of described silicic acid gel, and wash-out filtration is carried out to described silicic acid gel grain, obtain wash-out filter after the step of silicic acid gel grain be specially:
At 20 DEG C ~ 90 DEG C temperature, described silicic acid gel is added water ageing 2 ~ 48 hours, add the mineral acid that massfraction is 0.04 ~ 0.23%, add again described auxiliary agent regulate described in the add water pH value of silicic acid gel of ageing be 7, continue reaction 8 ~ 24 hours, generate silicic acid gel grain;
Described silicic acid gel grain wash-out under pH value is 6.5 ~ 8.0 conditions is filtered, and controls that foreign matter content is less than 10ppm, specific conductivity is less than or equal to 50 μ S/cm, obtain wash-out filter after silicic acid gel grain.
Preferably, described mineral acid be in sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, chloric acid any one or multiple.
Preferably, described auxiliary agent be in amino dodecane, urea, ammoniacal liquor, sequestrant, tensio-active agent any one or multiple.
Preferably, the massfraction of the auxiliary agent of the pH value of the described silicic acid gel for the ageing that adds water described in regulating is 0.01 ~ 0.25%.
Further, on a preset condition based described, the silicic acid gel grain after being filtered by described wash-out dries calcination, and the step obtaining large pore volume silica-gel carrier is specially:
At 100 DEG C ~ 500 DEG C temperature, the silicic acid gel grain after being filtered by described wash-out dries calcination 3 ~ 18 hours, obtains large pore volume silica-gel carrier.
Beneficial effect of the present invention is:
1, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention, its pore volume can at 2.0 ~ 3.5ml/g, or larger, and bulk specific gravity is less than 300g/L, and aperture is greater than 40nm.
2, the preparation method of large pore volume silica-gel carrier of the present invention, its raw material is easy to get, with low cost, simple to operate, does not need complicated technique and facility, does not increase extras and drops into, and is easy to quantize to produce.
3, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention; compared with existing silica-gel carrier; Application Areas is expanded; part macroporous resin can be replaced, the effect that can not be substituted is played to the application in the fields such as high-end electronic, pottery, high-grade paint, food sanitation, rubber, biological medicine, household chemicals, environment protection, petrochemical complex, new forms of energy battery material, aerospace and military technique and new product development.
4, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention, to exceed or identical with the performance of world-class product, the expensive goods of most of dependence on import can have been replaced, and foreign exchange earning can have been realized, wide market, can realize higher economic benefit.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the flow chart of steps of the preparation method of a kind of large pore volume silica-gel carrier of the present invention.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.
As shown in Figure 1, the preparation method of a kind of large pore volume silica-gel carrier of the present invention, comprises the following steps:
Hydrolysis silicon source, auxiliary agent and deionized water are mixed and sedimentation and filtration according to preset ratio, generates silicon hydrating solution for subsequent use;
The mineral acid being diluted to preset concentration is mixed with described silicon hydrating solution and generates silicic acid sol;
Regulate the pH value of described silicic acid sol to producing silicic acid gel;
On a preset condition based silicic acid gel grain is generated to the ageing that adds water of described silicic acid gel, and wash-out filtration is carried out to described silicic acid gel grain, obtain wash-out filter after silicic acid gel grain;
On a preset condition based, the silicic acid gel grain after being filtered by described wash-out dries calcination, obtains large pore volume silica-gel carrier.
There is provided the embodiment of the preparation method of a kind of large pore volume silica-gel carrier of the present invention below, to be described further:
1, hydrolysis silicon source, auxiliary agent and deionized water is even according to the mixed in molar ratio of 45 ~ 80:0.05 ~ 2:20 ~ 50, at 15 DEG C ~ 35 DEG C temperature, be mixed with the solution of 12 ~ 30 degree Beaume, generate silicon hydrating solution after sedimentation and filtration for subsequent use.Wherein, the mol ratio of described hydrolysis silicon source, auxiliary agent and deionized water can be selected according to actual needs, such as, be hydrolyzed silicon source, auxiliary agent and the deionized water mixed in molar ratio according to 65:1.05:35; Described temperature can according to practical situation, and the such as difference of four seasons temperature, selects different temperature, as long as in temperature range, such as spring, summer, autumn, winter select 18 DEG C, 32 DEG C, 20 DEG C, 15 DEG C respectively; The degree Beaume of described solution can according to the actual temp selected, and means obtain by experiment, and this is the common practise of those skilled in the art, no longer repeats at this.
Wherein, preferably, described hydrolysis silicon source be in water glass, tetraethoxy, TMOS any one or multiple, certainly, can select other can be used as hydrolysis silicon source material, the present invention does not limit this.
2, mineral acid being diluted to concentration is 3.02mol/L ~ 21.38mol/L;
Described silicon hydrating solution being added described concentration is carry out mixing in the mineral acid of 3.02mol/L ~ 21.38mol/L to generate silicic acid sol
3, regulate the pH value of described silicic acid sol to producing silicic acid gel.
4, at 20 DEG C ~ 90 DEG C temperature, described silicic acid gel is added water ageing 2 ~ 48 hours, add the mineral acid that massfraction is 0.04 ~ 0.23%, add again described auxiliary agent regulate described in the add water pH value of silicic acid gel of ageing be 7, continue reaction 8 ~ 24 hours, generate silicic acid gel grain;
Described silicic acid gel grain wash-out under pH value is 6.5 ~ 8.0 conditions is filtered, and controls that foreign matter content is less than 10ppm, specific conductivity is less than or equal to 50 μ S/cm, obtain wash-out filter after silicic acid gel grain.
Wherein, preferably, described in this step for regulating the massfraction of the auxiliary agent of the pH value of the silicic acid gel of the ageing that adds water to be 0.01 ~ 0.25%.
Wherein, described impurity is specially metal-salt or other material.
5, at 100 DEG C ~ 500 DEG C temperature, the silicic acid gel grain after being filtered by described wash-out dries calcination 3 ~ 18 hours, obtains large pore volume silica-gel carrier.
Wherein, preferably, described mineral acid be in sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, chloric acid any one or multiple, certainly, can select other mineral acid, the present invention does not limit this.
Wherein, preferably, described auxiliary agent be in amino dodecane, urea, ammoniacal liquor, sequestrant, tensio-active agent any one or multiple, certainly, can select other similar auxiliary agent, the present invention does not limit this.Wherein, sequestrant can be Acetyl Acetone, dithizone etc., and tensio-active agent can be non-ionic type alkenyl sulphonate etc.
The preparation method of large pore volume silica-gel carrier of the present invention, advantage is:
1, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention, its pore volume can at 2.0 ~ 3.5ml/g, or larger, and bulk specific gravity is less than 300g/L, and aperture is greater than 40nm.
2, the preparation method of large pore volume silica-gel carrier of the present invention, its raw material is easy to get, with low cost, simple to operate, does not need complicated technique and facility, does not increase extras and drops into, and is easy to quantize to produce.
3, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention; compared with existing silica-gel carrier; Application Areas is expanded; part macroporous resin can be replaced, the effect that can not be substituted is played to the application in the fields such as high-end electronic, pottery, high-grade paint, food sanitation, rubber, biological medicine, household chemicals, environment protection, petrochemical complex, new forms of energy battery material, aerospace and military technique and new product development.
4, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention, to exceed or identical with the performance of world-class product, the expensive goods of most of dependence on import can have been replaced, and foreign exchange earning can have been realized, wide market, can realize higher economic benefit.
5, the silica-gel carrier that obtains of the preparation method of large pore volume silica-gel carrier of the present invention, the easier washing and filtering in wide aperture, save the energy, protection of the environment, reduce further cost.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (9)
1. a preparation method for large pore volume silica-gel carrier, is characterized in that, comprises the following steps:
Hydrolysis silicon source, auxiliary agent and deionized water are mixed and sedimentation and filtration according to preset ratio, generates silicon hydrating solution for subsequent use;
The mineral acid being diluted to preset concentration is mixed with described silicon hydrating solution and generates silicic acid sol;
Regulate the pH value of described silicic acid sol to producing silicic acid gel;
On a preset condition based silicic acid gel grain is generated to the ageing that adds water of described silicic acid gel, and wash-out filtration is carried out to described silicic acid gel grain, obtain wash-out filter after silicic acid gel grain;
On a preset condition based, the silicic acid gel grain after being filtered by described wash-out dries calcination, obtains large pore volume silica-gel carrier.
2. preparation method according to claim 1, is characterized in that, describedly hydrolysis silicon source, auxiliary agent and deionized water to be mixed and sedimentation and filtration according to preset ratio, and the step generating silicon hydrating solution for subsequent use is specially:
Hydrolysis silicon source, auxiliary agent and deionized water is even according to the mixed in molar ratio of 45 ~ 80:0.05 ~ 2:20 ~ 50, at 15 DEG C ~ 35 DEG C temperature, be mixed with the solution of 12 ~ 30 degree Beaume, generate silicon hydrating solution after sedimentation and filtration for subsequent use.
3. preparation method according to claim 2, is characterized in that, described hydrolysis silicon source be in water glass, tetraethoxy, TMOS any one or multiple.
4. preparation method according to claim 3, is characterized in that, describedly the mineral acid being diluted to preset concentration is mixed with described silicon hydrating solution the step generating silicic acid sol is specially:
Mineral acid being diluted to concentration is 3.02mol/L ~ 21.38mol/L;
Described silicon hydrating solution being added described concentration is carry out mixing in the mineral acid of 3.02mol/L ~ 21.38mol/L to generate silicic acid sol.
5. preparation method according to claim 4, it is characterized in that, describedly on a preset condition based silicic acid gel grain is generated to the ageing that adds water of described silicic acid gel, and wash-out filtration is carried out to described silicic acid gel grain, obtain wash-out filter after the step of silicic acid gel grain be specially:
At 20 DEG C ~ 90 DEG C temperature, described silicic acid gel is added water ageing 2 ~ 48 hours, add the mineral acid that massfraction is 0.04 ~ 0.23%, add again described auxiliary agent regulate described in the add water pH value of silicic acid gel of ageing be 7, continue reaction 8 ~ 24 hours, generate silicic acid gel grain;
Described silicic acid gel grain wash-out under pH value is 6.5 ~ 8.0 conditions is filtered, and controls that foreign matter content is less than 10ppm, specific conductivity is less than or equal to 50 μ S/cm, obtain wash-out filter after silicic acid gel grain.
6. preparation method according to claim 5, is characterized in that, described mineral acid be in sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, chloric acid any one or multiple.
7. preparation method according to claim 6, is characterized in that, described auxiliary agent be in amino dodecane, urea, ammoniacal liquor, sequestrant, tensio-active agent any one or multiple.
8. preparation method according to claim 7, is characterized in that, the massfraction of the auxiliary agent of the pH value of the described silicic acid gel for the ageing that adds water described in regulating is 0.01 ~ 0.25%.
9. preparation method according to claim 8, is characterized in that, on a preset condition based described, and the silicic acid gel grain after being filtered by described wash-out dries calcination, and the step obtaining large pore volume silica-gel carrier is specially:
At 100 DEG C ~ 500 DEG C temperature, the silicic acid gel grain after being filtered by described wash-out dries calcination 3 ~ 18 hours, obtains large pore volume silica-gel carrier.
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US5231066A (en) * | 1991-09-11 | 1993-07-27 | Quantum Chemical Corporation | Bimodal silica gel, its preparation and use as a catalyst support |
GB2269377A (en) * | 1992-08-07 | 1994-02-09 | British Petroleum Co Plc | Silica gel and process for making it from polysilicic acid |
CN1403486A (en) * | 2001-09-03 | 2003-03-19 | 中国石油天然气股份有限公司 | Preparation method of silica gel carrier |
CN1522958A (en) * | 2003-02-21 | 2004-08-25 | 青岛海洋化工有限公司 | Process for manufacturing macroreticular spherical silica gel |
CN102745698A (en) * | 2011-04-22 | 2012-10-24 | 中国石油天然气股份有限公司 | Preparation method of carrier silica gel |
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
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US5231066A (en) * | 1991-09-11 | 1993-07-27 | Quantum Chemical Corporation | Bimodal silica gel, its preparation and use as a catalyst support |
GB2269377A (en) * | 1992-08-07 | 1994-02-09 | British Petroleum Co Plc | Silica gel and process for making it from polysilicic acid |
CN1403486A (en) * | 2001-09-03 | 2003-03-19 | 中国石油天然气股份有限公司 | Preparation method of silica gel carrier |
CN1522958A (en) * | 2003-02-21 | 2004-08-25 | 青岛海洋化工有限公司 | Process for manufacturing macroreticular spherical silica gel |
CN102745698A (en) * | 2011-04-22 | 2012-10-24 | 中国石油天然气股份有限公司 | Preparation method of carrier silica gel |
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