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CN102002120A - Method for preparing special silica gel carrier with large pore volume and large specific surface area - Google Patents

Method for preparing special silica gel carrier with large pore volume and large specific surface area Download PDF

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Publication number
CN102002120A
CN102002120A CN 201010287087 CN201010287087A CN102002120A CN 102002120 A CN102002120 A CN 102002120A CN 201010287087 CN201010287087 CN 201010287087 CN 201010287087 A CN201010287087 A CN 201010287087A CN 102002120 A CN102002120 A CN 102002120A
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specific surface
mass content
control agent
surface control
drying
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胡毅
刘红光
于海斌
郑书忠
尹世容
郑秋红
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China National Offshore Oil Corp CNOOC
CNOOC Tianjin Chemical Research and Design Institute Co Ltd
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China National Offshore Oil Corp CNOOC
CNOOC Tianjin Chemical Research and Design Institute Co Ltd
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Abstract

The invention relates to a method for preparing a special silica gel carrier with a large pore volume and a large specific surface area. The method is characterized by comprising the following process steps of: diluting industrial sodium silicate; adding inorganic acid solution dropwise at the initial temperature of between 20 and 40 DEG C, adjusting the pH value of a system to be 2 to 4, heating to the final temperature of between 80 and 100 DEG C and adding a specific surface control agent which may be one or more of glycol, ethyl acetate, glycerol, acetone and trichloroethane; preserving the heat for 2 to 4 hours and performing a hydro-thermal reaction; ageing for 1 to 2 hours; washing; drying; and performing particle size classification to obtain the final product.

Description

A kind of preparation method of large pore volume bigger serface special silica-gel carrier
Technical field
The present invention relates to a kind of preparation method of silica gel, more particularly, relate to the preparation method who is suitable as high reactivity gas phase ethene polymerization catalyst special silica-gel carrier.
Background technology
In gas phase polymerization polyethylene catalysts preparation process, silica gel is used widely as a kind of carrier at present.The catalyzer that utilizes this carrier to make is mainly used in the production of LLDPE.The present silica-gel carrier that uses, its pore property is: pore volume 1.6ml/g, specific surface area, 300-350m2/g, mean particle size: 40-50 micron.Utilize the catalyst activity of this preparing carriers can only reach 3000-4000gPE/gcat, make poly production cost high like this, external current research shows, utilize large pore volume, bigger serface special silica-gel carrier, the catalyst activity of preparation can reach 6000-7000gPE/gcat, can make like this under the constant situation of production equipment production efficiency is increased substantially, production cost is further reduced.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 micron.The method of U5625023 patent disclosure is that potassium or sodium silicate and mineral acid mix the formation hydrogel by a special nozzle, and washing, drying obtain specific surface 10-1000m then 2/ g, pore volume: 0.5-2.5ml/g, aperture
Figure BSA00000277361600011
Silica-gel carrier.A kind of preparation method of silica-gel carrier is disclosed in patent CN1403486, when the preparation hydrogel, employing is a mother liquor with part dilute silicate solution, dilute silicate solution and mineral acid add in the reactor that mother liquor is housed simultaneously, treat to regulate when partial gel occurs the mother liquor PH5-8.5 water-sol and be converted into hydrogel fully, through the silica-gel carrier that aging, washing, drying obtain, specific surface area: 200-400m 2/ g, pore volume: 1.0-2.0ml/.
Introduced a kind of preparation method of macroporous particle silica gel in CN02127599.8, described method is because pore volume has only 0.8-1.1ml/g to be not suitable for doing the use of ethylene rolymerization catalyst carrier.Because it is relatively stricter to the requirement of activity of such catalysts and granularity to produce poly production as vapor phase process, must to be a kind of polymerizing catalyst efficiently be mainly three aspects for the requirement of carrier silica gel with employed catalyzer.1, chemical purity, 2, pore property, 3, size-grade distribution.These three conditions must all will satisfy, and could use as support of the catalyst like the gas phase polymerization polyethylene.Therefore, we have invented the large pore volume that is suitable for gas phase ethene polymerization and uses, the preparation method of bigger serface special silica-gel carrier.
Summary of the invention
The objective of the invention is to adopt industrial metasilicate is raw material, a kind of large pore volume that highly active gas phase ethene polymerization uses, preparation method of bigger serface special silica-gel carrier of being fit to is provided, adopt this method, the special silica-gel carrier of producing, its granularity, overall target excellences such as aperture, pore volume and specific surface area, thereby can be as the gas phase ethene polymerization catalyst carrier.
A kind of preparation method of large pore volume bigger serface special silica-gel carrier is characterized in that:
Processing step comprises:
1, be the industrial metasilicate of 3.1-3.4 with modulus, the mass content that is diluted to concentration and is silicon-dioxide is a 10-20% industrial metasilicate solution; Down dripping mass content at initial temperature 20-40 ℃ is the inorganic acid solution of 15-25%, and mineral acid is selected from one or more of sulfuric acid, nitric acid, phosphoric acid; Regulation system PH to 2-4, keeping the final pH value of regulating is 3-4;
2, be warming up to outlet temperature 80-100 ℃, add the specific surface control agent; The specific surface control agent is selected from ethylene glycol, ethyl acetate, glycerol, and acetone, one or more of trichloroethane, the add-on of specific surface control agent is the 1-5% of water glass mass content;
3, with outlet temperature insulation 2-4 hour, carry out hydro-thermal reaction; At room temperature ageing 1-2 hour then; Wash, mode of washing is selected from washing, one or more that alcohol is washed, and being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 400-600 ℃; Carry out size classification then, obtain the finished product.
The pore property that obtains the finished product is:
Silicon-dioxide: greater than 99.7%; Pore volume: 2.5-2.8ml/g; Specific surface area: 500-600m2/g; Mean particle size 50-150 micron.
Foregoing invention is by kind of regulating initial temperature, outlet temperature and specific surface control agent and the purpose that content reaches the adjustment hole characteristic.The pore property of different types of specific surface control product is different.
The preferred technical solution of the present invention: it is characterized in that:
Processing step comprises:
1, be the industrial metasilicate of 3.2-3.3 with modulus, the mass content that is diluted to concentration and is silicon-dioxide is a 15-20% industrial metasilicate solution; Down dripping mass content at initial temperature 30-40 ℃ is the inorganic acid solution of 15-25%, and mineral acid is selected from one or more of sulfuric acid, nitric acid, phosphoric acid; Regulation system PH to 3-4, keeping the final pH value of regulating is 3.5-4;
2, be warming up to outlet temperature 90-100 ℃, add the specific surface control agent; The specific surface control agent is selected from ethylene glycol, ethyl acetate, glycerol, and acetone, one or more of trichloroethane, the add-on of specific surface control agent is the 1-4% of water glass mass content;
3, with outlet temperature insulation 3-4 hour, carry out hydro-thermal reaction; At room temperature ageing 1-1.5 hour then, washing, drying is carried out size classification then, obtains the finished product.
The invention has the advantages that: adopt technology of the present invention, make the physical and chemical performance of this silica-gel carrier reach, dioxide-containing silica (butt) is greater than 99.7%, and the BET specific surface area is 450-600m 2/ g, volume of voids are 2.0-2.7, and mean particle size is the index request of 75-150 μ m.Whole technological process need not to use the strict process raw material, and the reaction times of the present invention is 2-5 hour.Hydro-thermal reaction adds the specific surface control agent simultaneously, and in reaction process, the primary particle of hydrogel is grown up gradually and rearranged.Organic solvent molecule and silica gel surface hydroxyl carry out graft reaction and through spraying drying rapid drying, have prevented the contraction in aperture, thereby silica gel structure is fixed up at last.The present invention adopts the prepared special silica-gel carrier dioxide-containing silica of common raw material greater than 99.7%.
Embodiment
Embodiment one,
1, with modulus be 3.1 industrial metasilicate, the mass content that is diluted to concentration and is silicon-dioxide is 10% industrial metasilicate solution; Dripping mass content down 20 ℃ of initial temperatures is 25% sulphuric acid soln, regulation system PH to 2-4, and keeping the final pH value of regulating is 3.5-4;
2, be warming up to outlet temperature 95-100 ℃, add specific surface control agent glycerol, the add-on of specific surface control agent is 1% of a water glass mass content;
3, with outlet temperature insulation 2 hours, carry out hydro-thermal reaction; Ageing at room temperature is 2 hours then; Wash, being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 400 ℃; Carry out size classification then, mean particle size 75-150 micron obtains moisture less than 10% macroporous microsphere silica gel the finished product.
Its experimental data such as table one.
Table one: the physical and chemical performance table of special silica-gel carrier embodiment
Figure BSA00000277361600051
Embodiment two,
1, with modulus be 3.2 industrial metasilicate, the mass content that is diluted to concentration and is silicon-dioxide is 15% industrial metasilicate solution; Dripping mass content down 30 ℃ of initial temperatures is 20% sulphuric acid soln, regulation system PH to 2-4, and keeping the final pH value of regulating is 3.5-4;
2, be warming up to outlet temperature 80-85 ℃, add specific surface control agent ethyl acetate, the add-on of specific surface control agent respectively is 3% of a water glass mass content;
3, with outlet temperature insulation 3 hours, carry out hydro-thermal reaction; Ageing at room temperature is 1 hour then; Wash, being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 500 ℃; Carry out size classification then, mean particle size 75-150 micron obtains moisture less than 10% macroporous microsphere silica gel the finished product.
Its experimental data such as table two.
Table two: the physical and chemical performance table of special silica-gel carrier embodiment
Figure BSA00000277361600061
Embodiment three:
1, with modulus be 3.3 industrial metasilicate, the mass content that is diluted to concentration and is silicon-dioxide is 20% industrial metasilicate solution; Dripping mass content down 40 ℃ of initial temperatures is 18% sulphuric acid soln, regulation system PH to 2-4, and keeping the final pH value of regulating is 3.5-4;
2, be warming up to outlet temperature 90-95 ℃, add specific surface control agent ethylene glycol, the add-on of specific surface control agent is 3% of a water glass mass content;
3, with outlet temperature insulation 2 hours, carry out hydro-thermal reaction; Ageing at room temperature is 2 hours then; Wash, being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 600 ℃; Carry out size classification then, mean particle size 75-150 micron obtains moisture less than 10% macroporous microsphere silica gel the finished product.
Its experimental data such as table three.
Table three: the physical and chemical performance table of special silica-gel carrier embodiment
Figure BSA00000277361600071
Embodiment four:
1, with modulus be 3.4 industrial metasilicate, the mass content that is diluted to concentration and is silicon-dioxide is 20% industrial metasilicate solution; Dripping mass content down 20 ℃ of initial temperatures is 15% sulphuric acid soln, regulation system PH to 2-4, and keeping the final pH value of regulating is 3.5-4;
2, be warming up to outlet temperature 95-100 ℃, add specific surface control agent glycerol and acetone mixed solution, glycerol and acetone mass content respectively account for 50%, and the add-on of specific surface control agent is 4% of a water glass mass content;
3, with outlet temperature insulation 2 hours, carry out hydro-thermal reaction; Ageing at room temperature is 2 hours then; Wash, being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 400 ℃; Carry out size classification then, mean particle size 75-150 micron obtains moisture less than 10% macroporous microsphere silica gel the finished product.
Its experimental data such as table four.
Table four: the physical and chemical performance table of special silica-gel carrier embodiment
Figure BSA00000277361600081

Claims (2)

1. the preparation method of a large pore volume bigger serface special silica-gel carrier is characterized in that:
Processing step comprises:
1) be the industrial metasilicate of 3.1-3.4 with modulus, the mass content that is diluted to concentration and is silicon-dioxide is the industrial metasilicate solution of 10-20%; Down dripping mass content at initial temperature 20-40 ℃ is the inorganic acid solution of 15-25%, and mineral acid is selected from one or more of sulfuric acid, nitric acid, phosphoric acid; Regulation system PH to 2-4, keeping the final pH value of regulating is 3-4;
2) be warming up to outlet temperature 80-100 ℃, add the specific surface control agent; The specific surface control agent is selected from ethylene glycol, ethyl acetate, glycerol, and acetone, one or more of trichloroethane, the add-on of specific surface control agent is the 20-30% of water glass mass content;
3) with outlet temperature insulation 2-4 hour, carry out hydro-thermal reaction; At room temperature ageing 1-2 hour then; Wash, mode of washing is selected from washing, one or more that alcohol is washed, and being washed to the sodium ion mass content is below 0.05%; Drying, drying mode adopts spraying drying: temperature keeps 400-600 ℃; Carry out size classification then, obtain the finished product.
The pore property that obtains the finished product is:
Silicon-dioxide: greater than 99.7%; Pore volume: 2.5-2.8ml/g; Specific surface area: 500-600m2/g; Mean particle size 50-150 micron.
2. according to the described preparation method of claim 1, it is characterized in that:
Processing step comprises:
1) be the industrial metasilicate of 3.2-3.3 with modulus, the mass content that is diluted to concentration and is silicon-dioxide is the industrial metasilicate solution of 15-20%; Down dripping mass content at initial temperature 30-40 ℃ is the inorganic acid solution of 15-25%, and mineral acid is selected from one or more of sulfuric acid, nitric acid, phosphoric acid; Regulation system PH to 3-4, keeping the final pH value of regulating is 3.5-4;
2) be warming up to outlet temperature 90-100 ℃, add the specific surface control agent; The specific surface control agent is selected from ethylene glycol, ethyl acetate, glycerol, and acetone, one or more of trichloroethane, the add-on of specific surface control agent is the 20-25% of water glass mass content;
3) with outlet temperature insulation 3-4 hour, carry out hydro-thermal reaction; Ageing at room temperature then, washing, drying is carried out size classification then, obtains the finished product.
CN 201010287087 2010-09-20 2010-09-20 Method for preparing special silica gel carrier with large pore volume and large specific surface area Pending CN102002120A (en)

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102145897A (en) * 2011-04-19 2011-08-10 冷水江三A化工有限责任公司 Large-pore-volume silicon dioxide with nanoparticle structure and preparation method thereof
CN102382216A (en) * 2011-05-26 2012-03-21 中国海洋石油总公司 Preparation method of silica gel carrier for ethylene polymerization catalyst
CN102530970A (en) * 2012-03-01 2012-07-04 冷水江三A化工有限责任公司 Preparation method of toothpaste abrasive silicon dioxide
CN102960560A (en) * 2012-11-23 2013-03-13 重庆优宝生物技术有限公司 Composite acidifier for reducing post-weaning diarrhea rate
CN103464216A (en) * 2013-09-26 2013-12-25 中国海洋石油总公司 Preparation method of silica gel carrier of heteropoly acid catalyst for synthesizing sec-butyl acetate from acetic acid and butylene
CN105813977A (en) * 2013-12-12 2016-07-27 日产化学工业株式会社 Silica particle, method for producing same, and silica sol
CN108794667A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 Silica-gel carrier and loaded catalyst and preparation method thereof
CN108794668A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 Silica-gel carrier and loaded catalyst and preparation method thereof
CN108794666A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 The method and polyethylene of vinyl polymerization
CN108794665A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 The method and polyethylene of vinyl polymerization
CN111072818A (en) * 2018-10-22 2020-04-28 中国石油化工股份有限公司 Metallocene catalyst and preparation method thereof
CN111072798A (en) * 2018-10-22 2020-04-28 中国石油化工股份有限公司 Silica gel and preparation method and application thereof

Citations (3)

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Publication number Priority date Publication date Assignee Title
CN1403486A (en) * 2001-09-03 2003-03-19 中国石油天然气股份有限公司 A kind of preparation method of silica gel carrier
CN1978470A (en) * 2006-11-22 2007-06-13 天津化工研究设计院 Method for preparing macroporous silicon rubber carrier for ethylene polymerization catalyst by vapour process
CN101624431A (en) * 2009-08-19 2010-01-13 中国海洋石油总公司 Method for preparing special silica-gel carrier of ethylene polymerization catalyst in a slurry process

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1403486A (en) * 2001-09-03 2003-03-19 中国石油天然气股份有限公司 A kind of preparation method of silica gel carrier
CN1978470A (en) * 2006-11-22 2007-06-13 天津化工研究设计院 Method for preparing macroporous silicon rubber carrier for ethylene polymerization catalyst by vapour process
CN101624431A (en) * 2009-08-19 2010-01-13 中国海洋石油总公司 Method for preparing special silica-gel carrier of ethylene polymerization catalyst in a slurry process

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102145897B (en) * 2011-04-19 2012-10-24 冷水江三A化工有限责任公司 Large-pore-volume silicon dioxide with nanoparticle structure and preparation method thereof
CN102145897A (en) * 2011-04-19 2011-08-10 冷水江三A化工有限责任公司 Large-pore-volume silicon dioxide with nanoparticle structure and preparation method thereof
CN102382216A (en) * 2011-05-26 2012-03-21 中国海洋石油总公司 Preparation method of silica gel carrier for ethylene polymerization catalyst
CN102382216B (en) * 2011-05-26 2013-01-16 中国海洋石油总公司 Preparation method of silica gel carrier for ethylene polymerization catalyst
CN102530970B (en) * 2012-03-01 2014-02-19 冷水江三A化工有限责任公司 Preparation method of toothpaste abrasive silicon dioxide
CN102530970A (en) * 2012-03-01 2012-07-04 冷水江三A化工有限责任公司 Preparation method of toothpaste abrasive silicon dioxide
CN102960560B (en) * 2012-11-23 2014-09-10 重庆优宝生物技术有限公司 Composite acidifier for reducing post-weaning diarrhea rate
CN102960560A (en) * 2012-11-23 2013-03-13 重庆优宝生物技术有限公司 Composite acidifier for reducing post-weaning diarrhea rate
CN103464216A (en) * 2013-09-26 2013-12-25 中国海洋石油总公司 Preparation method of silica gel carrier of heteropoly acid catalyst for synthesizing sec-butyl acetate from acetic acid and butylene
CN105813977A (en) * 2013-12-12 2016-07-27 日产化学工业株式会社 Silica particle, method for producing same, and silica sol
CN108794667A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 Silica-gel carrier and loaded catalyst and preparation method thereof
CN108794668A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 Silica-gel carrier and loaded catalyst and preparation method thereof
CN108794666A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 The method and polyethylene of vinyl polymerization
CN108794665A (en) * 2017-05-05 2018-11-13 中国石油化工股份有限公司 The method and polyethylene of vinyl polymerization
CN111072818A (en) * 2018-10-22 2020-04-28 中国石油化工股份有限公司 Metallocene catalyst and preparation method thereof
CN111072798A (en) * 2018-10-22 2020-04-28 中国石油化工股份有限公司 Silica gel and preparation method and application thereof
CN111072818B (en) * 2018-10-22 2022-10-14 中国石油化工股份有限公司 Metallocene catalyst and preparation method thereof
CN111072798B (en) * 2018-10-22 2022-10-14 中国石油化工股份有限公司 Silica gel and preparation method and application thereof

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Application publication date: 20110406