CN1803600A - Preparation method of silica gel carrier - Google Patents
Preparation method of silica gel carrier Download PDFInfo
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- CN1803600A CN1803600A CN 200510129965 CN200510129965A CN1803600A CN 1803600 A CN1803600 A CN 1803600A CN 200510129965 CN200510129965 CN 200510129965 CN 200510129965 A CN200510129965 A CN 200510129965A CN 1803600 A CN1803600 A CN 1803600A
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Abstract
The preparation method for silicagel carrier for polyolefin catalyst comprises: preparing silicate solution A with surfactant and dilute inorgaci acid solution B; adding solution A and B into reaction kettle, adjusting B solution for constant-temperature ageing; cooling, adding ammonium salt into the solution; after separating solid, filtering ,clearing, drying, grinding, and baking to obtain the objective product. This invention uses co-current flow method to form a great deal of crystal hucleus, decreases particle agglomeration and forms pore by space buffer action of surfactant, and can change the specific surface area and size and pore distribution of silicagel.
Description
Technical field
The present invention relates to a kind of silica-gel carrier, especially relate to a kind of preparation method who is used for the silica-gel carrier of polyolefin catalyst.
Background technology
Polyolefin catalyst is except the Ziegler-Natta homogeneous catalyst, and metallocene calalyst for polymerization of olefine all is carrier with silica gel.The preparation method of silica gel has more patent report, as US5231066, and JP2003192713, EP0505583, US5895770, US4100105, US4892853, US5372983 etc.US5625013 patent (Preparation ofa supported catalyst forthe polymerization of alpha-olefins) disclosed method is by forming hydrogel in the inorganic acid aqueous solution of special spray tube with sodium or potash water glass importing whirlpool, without aging, it is 10～300nm that direct washing and drying obtain diameter, and specific surface area is 10～1000m
2/ g, pore volume are 0.5～2.5cm
3/ g, the aperture is the silica-gel carrier of 40～200 .Yao Peihong etc. disclose a kind of preparation method of silica-gel carrier in patent (CN1403486), when preparation silicon gel, having adopted with part dilute silicate solution is mother liquor, dilute silicate and mineral acid add in the reactor that mother liquor is housed simultaneously, when treating that colloidal sol and partial gel occur, regulate pH value to 5～8.5 of mother liquor, the water-sol is converted into the silicon gel fully, and obtaining specific surface area through aging, washing, processing and drying again is 200～400m
2/ g, pore size distribution are 8～15nm, and bulk density is 0.2～0.4g/ml, and pore volume is the silica-gel carrier of 1.0～2.0ml/g.It is 1.00～2.00ml/g that the polyolefin catalyst that uses on polyolefin industry requires the pore volume of silica-gel carrier, and specific surface area is 280～555m
2/ g, most probable pore size distribution are 9～18nm.
Other has some patents, contains some other elements when preparation polyolefin catalyst silica-gel carrier.As the patent report of US5895770 (Olefin polymerization catalysts with specific silica supports), contain Ti, Al, B, Mn or other elements of total amount 5% (w/w) in the prepared silica gel.The patent of US4100105 (Titanium-modified silyl chromatecatalysts for ethylene polymerization) has proposed to contain the Al of the Cr and 0.01%～50% (w/w) of 0.05%～2.0% (w/w) in silica-gel carrier.The component of the silica gel of these patent preparations is more, and preparation process is complicated.
Summary of the invention
Purpose of the present invention is intended to the shortcoming that exists among the existing silica-gel carrier preparation method, provides a kind of in the presence of tensio-active agent, adopts stream injection mode also to prepare the method for the silica-gel carrier that is used for polyolefin catalyst.Its preparation method is simple, and technical process is short.
Step of the present invention is as follows:
1) preparation contains the silicate solutions A of tensio-active agent, the concentration of silicate solutions is 0.1～1.0mol/L, surfactant concentrations is 0.005～0.05mol/L, described tensio-active agent is selected from a kind of in Sodium dodecylbenzene sulfonate, sodium lauryl sulphate, polyoxyethylene laurel ether sodium sulfate, Soxylat A 25-7 and the tween series, and described silicate is selected from least a in water glass, potassium silicate, water glass and the organo-silicon ester;
2) preparation dilute inorganic acid solution B, the concentration of mineral acid is 0.1～1.0mol/L, described mineral acid is selected from a kind of in hydrochloric acid, sulfuric acid and the nitric acid;
3) flow velocity of A solution with 1～5ml/min is added in the reactor, add B solution simultaneously, regulate B solution, the pH value that makes solution in the reactor is 8～10, the control stirring velocity is at 2000～3000 commentaries on classics/min in reaction process, steady temperature is at 50～95 ℃, after dropwising, and the aging 1～2h of constant temperature under agitation;
4) the cooling back adds the ammonium salt that accounts for solution total amount 1%～5% in solution, treat that solid separates out after-filtration, washing, solid is at 110 ℃ of drying 3～4h, grind the back at 600～900 ℃ of following roasting 2～3h, the polyolefin catalyst silica-gel carrier, described ammonium salt is selected from a kind of in ammonium nitrate, ammonium sulfate, volatile salt, bicarbonate of ammonia and the ammonium chloride.
In step 1), organo-silicon ester is preferably tetraethyl silicate.
In step 2) in, the concentration of mineral acid is 0.3～0.6mol/L.
In step 3), preferably the flow velocity of A solution with 2～3ml/min is added in the reactor, the pH value of described solution is 8～8.5, preferably 85～90 ℃ of steady temperatures.
In step 4), described ammonium salt is ammonium nitrate preferably, and described maturing temperature is 700～800 ℃.
The present invention with two kinds of reactants uniform mixing at a terrific speed, forms a large amount of nucleus by cocurrent process in the solution of certain pH value, nucleus forms fine offspring, the SiO in this microenvironment under certain temperature and silicate concentration
2Particle is electronegative, and the particle of bear electricity is in high dispersing state (zeta-potential maximum) in solution, and the surfactant molecule in the solution is attached to SiO
2Particle surface or be present in SiO
2Between the particle, produce sterically hindered.Under negative charge and sterically hindered common influence, reduced SiO
2The speed of growth of particle hinders SiO
2Particle aggregation.In washing and drying process, because SiO is avoided in the protection of tensio-active agent
2The reunion again of particle, the tensio-active agent of burning in roasting process stays hole in silica gel, make silica gel have bigger specific surface and suitable most probable pore size distribution.By the kind and the maturing temperature of reconciliation statement surface-active agent, can change specific surface area, granular size and the pore size distribution of silica gel.Compared with prior art, preparation method of the present invention is simple, and technical process is short, uses conventional equipment to produce.
Embodiment
Further specify the present invention with embodiment below.
Embodiment 1:
Put into the 200ml deionized water in the reactor that agitator, temperature controller and pH meter are installed, start temperature controller and agitator, the temperature that makes reactor is 85 ℃, and stirring velocity is 3000 commentaries on classics/min.Obtain solution A, first compound concentration are the sodium silicate solution of 0.3mol/L, add the tensio-active agent Sodium dodecylbenzene sulfonate again in this solution, and the concentration that makes Sodium dodecylbenzene sulfonate is 0.01mol/l; Preparation sulphuric acid soln B, the concentration of B solution is 0.5mol/L.Speed with 3ml/min drips solution A, drips solution B simultaneously, makes the pH value of solution in the reactor remain at 8.0, keeps the temperature and the stirring velocity of reactor simultaneously.Solution A drips the back and stops to drip solution B, and under agitation constant temperature 1h is aging, standing over night at once.
Add the ammonium nitrate solid powder in above-mentioned solution, add-on is 2 (w/w) % of solution total amount, leaves standstill after the stirring, treats that solid separates out after-filtration, washs filtrate and do not contain Na
+And SO
4 2-Solid is dry 4h under 110 ℃, grinds the back at 700 ℃ of roasting 2h, and obtaining specific surface area is 272m
2/ g, most probable pore size distribution are 9.3748nm, and bulk density is 0.4921g/ml, and granularity is 30nm, the silica-gel carrier that connects of neck slightly between particle.
Embodiment 2:
Preparation process is with embodiment 1, and A solution mesosilicic acid na concn is 0.2mol/L, and sodium lauryl sulphate concentration is 0.01mol/l, and the pH value of drip added-time mixed solution is 8.5 o'clock, and the temperature of solution is 80 ℃, and resulting silica-gel carrier surface-area is 226m
2/ g, most probable pore size distribution are 7.4803nm, and bulk density is 0.4847g/ml, and granularity is 30nm.
Embodiment 3:
Preparation process is with embodiment 1, and A solution mesosilicic acid na concn is 0.5mol/L, and the concentration of tensio-active agent tween-80 is 0.015mol/L, and keeping the temperature of mixed solution is 80 ℃, and the pH value maintains at 8.0 o'clock, and resulting silica gel specific surface area is 255m
2/ g, most probable is distributed as 9.1850nm.Bulk density is 0.4389g/ml, and granularity is 30nm.
Embodiment 4:
Preparation process is with embodiment 1, the concentration of water glass is 0.3mol/L in the A solution, the concentration of Sodium dodecylbenzene sulfonate is 0.011mol/L, the flow velocity of A solution is 2ml/min, regulate the rate of addition of B solution, make the pH value of mixed solution maintain 8.5, temperature remains on 85 ℃, and the specific surface area of resulting silica gel is 282.9m after washing, drying, roasting
2/ g, most probable pore size distribution are 12nm, and pore volume is 1.0868ml/g, and bulk density is 0.4200g/ml, and particle diameter is 35nm.
Embodiment 5:
Preparation process is with embodiment 1, the concentration of water glass is 0.5mol/L in the A solution, the concentration of polyoxyethylene laurel ether sodium sulfate is 0.005mol/L, the flow velocity of A solution is 2.5ml/min, regulate the rate of addition of B solution, make the pH value of mixed solution maintain 8.0, temperature remains on 90 ℃, cooling back adds the volatile salt powder of 2% (w/w), waits to precipitate after separating out after filtration, the specific surface area of resulting silica gel is 260m after the washing, dry, roasting
2/ g, most probable pore size distribution are 10nm, pore volume 1.1055ml/g, and bulk density is 33nm for the 0.4180g/ml. particle diameter.
Embodiment 6:
Preparation process is with embodiment 1, the concentration of A solution mesosilicic acid ethyl ester is 0.5mol/L, the concentration of Soxylat A 25-7 is 0.02mol/L, the flow velocity of A solution is 2.0ml/min, regulate the rate of addition of B solution, make the pH value of mixed solution maintain 8.5, temperature remains on 85 ℃, cooling back adds the ammonium chloride powder of 2% (w/w), waits to precipitate after separating out after filtration, the specific surface area of resulting silica gel is 285m after the washing, dry, roasting
2/ g, most probable pore size distribution are 11nm, and pore volume is 1.0228ml/g, and bulk density is 0.4182g/ml, and particle diameter is 31nm.
Embodiment 7:
Preparation process embodiment 1, A solution contains water glass and potassium silicate, wherein the concentration of water glass is 0.3mol/L, the concentration of potassium silicate is 0.4mol/L, the concentration of the tensio-active agent sodium lauryl sulphate that adds is 0.04mol/L, the flow velocity of A solution is 2.5ml/min, regulate the rate of addition of B solution, make the pH value of mixed solution maintain 8.5, temperature remains on 95 ℃, cooling back adds the volatile salt powder of 2% (w/w), waits to precipitate after separating out after filtration, the specific surface area of resulting silica gel is 290m after the washing, dry, roasting
2/ g, most probable pore size distribution are 13nm, and pore volume is 1.2032ml/g, and bulk density is 0.4088g/ml, and particle diameter is 35nm.
Claims (10)
1, a kind of preparation method of silica-gel carrier is characterized in that its step is as follows:
1) preparation contains the silicate solutions A of tensio-active agent, the concentration of silicate solutions is 0.1～1.0mol/L, surfactant concentrations is 0.005～0.05mol/L, described silicate is selected from least a in water glass, potassium silicate, water glass and the organo-silicon ester, and described tensio-active agent is selected from a kind of in Sodium dodecylbenzene sulfonate, sodium lauryl sulphate, polyoxyethylene laurel ether sodium sulfate, Soxylat A 25-7 and the tween series;
2) preparation dilute inorganic acid solution B, the concentration of mineral acid is 0.1～1.0mol/L, described mineral acid is selected from a kind of in hydrochloric acid, sulfuric acid and the nitric acid;
3) flow velocity of A solution with 1～5ml/min is added in the reactor, add B solution simultaneously, regulate B solution, the pH value that makes solution in the reactor is 8～10, the control stirring velocity is at 2000～3000 commentaries on classics/min in reaction process, steady temperature is at 50～95 ℃, after dropwising, and the aging 1～2h of constant temperature under agitation;
4) the cooling back adds the ammonium salt that accounts for solution total amount 1%～5% in solution, treat that solid separates out after-filtration, washing, solid is at 110 ℃ of drying 3～4h, grind the back at 600～900 ℃ of following roasting 2～3h, the polyolefin catalyst silica-gel carrier, described ammonium salt is selected from a kind of in ammonium nitrate, ammonium sulfate, volatile salt, bicarbonate of ammonia and the ammonium chloride.
2, the preparation method of a kind of silica-gel carrier as claimed in claim 1, the concentration that it is characterized in that described silicate solutions is 0.3～0.5mol/L.
3, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that described surfactant concentrations is 0.008～0.02mol/L.
4, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that described organo-silicon ester is a tetraethyl silicate.
5, the preparation method of a kind of silica-gel carrier as claimed in claim 1, the concentration that it is characterized in that described mineral acid is 0.3～0.6mol/L.
6, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that in step 3), and described flow velocity is 2～3ml/min.
7, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that in step 3), and the pH value of described solution is 8～8.5.
8, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that in step 3), and described steady temperature is 85～90 ℃.
9, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that in step 4), and described ammonium salt is an ammonium nitrate.
10, the preparation method of a kind of silica-gel carrier as claimed in claim 1 is characterized in that in step 4), and described maturing temperature is 700～800 ℃.
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| CNB2005101299651A CN100436316C (en) | 2005-12-16 | 2005-12-16 | Preparation method of silica gel carrier |
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| CNB2005101299651A CN100436316C (en) | 2005-12-16 | 2005-12-16 | Preparation method of silica gel carrier |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101829571A (en) * | 2010-06-08 | 2010-09-15 | 厦门大学 | Method for preparing Cu/SiO2 catalyst |
| 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 |
| CN102399330A (en) * | 2010-09-15 | 2012-04-04 | 中国石油天然气股份有限公司 | Preparation method of high-purity modified silica gel carrier |
| 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 |
| CN102794202A (en) * | 2012-08-17 | 2012-11-28 | 垦利三合新材料科技有限责任公司 | Preparation method of aperture controllable catalyst carrier silicone |
| CN104650267A (en) * | 2013-11-19 | 2015-05-27 | 中国石油天然气股份有限公司 | Preparation method of double-peak pore-structure carrier silica gel |
| CN106477587A (en) * | 2015-08-25 | 2017-03-08 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN113248639A (en) * | 2021-06-01 | 2021-08-13 | 上海弘岸化工有限公司 | Silica gel supported polyolefin catalyst and preparation method and application thereof |
| CN113277680A (en) * | 2021-06-02 | 2021-08-20 | 渭南师范学院 | Method for treating heavy metal ions in chemical wastewater by using silicon dioxide |
| CN113583160A (en) * | 2021-09-14 | 2021-11-02 | 无锡玖汇科技有限公司 | Preparation method of composite carrier |
| CN113583159A (en) * | 2021-09-14 | 2021-11-02 | 无锡玖汇科技有限公司 | Supported polyolefin catalyst and preparation method thereof |
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| US4100105A (en) * | 1977-01-21 | 1978-07-11 | Union Carbide Corporation | Titanium-modified silyl chromate catalysts for ethylene polymerization |
| CN1031749C (en) * | 1993-01-04 | 1996-05-08 | 青岛海洋化工厂 | Process for prodn. of silica gel and the products |
| US5372983A (en) * | 1993-05-24 | 1994-12-13 | W. R. Grace & Co.-Conn. | Preparation of catalysts and supports |
| US5895770A (en) * | 1995-02-28 | 1999-04-20 | Pq Corporation | Olefin polymerization catalysts with specific silica supports |
| JP3487987B2 (en) * | 1995-10-24 | 2004-01-19 | 水澤化学工業株式会社 | Spherical silica gel with increased macropores and method for producing the same |
| CN1081608C (en) * | 1996-08-13 | 2002-03-27 | 中国石化金陵石油化工公司 | Silica gel prepn. method capable of regulating its pore structure |
| CN1158310C (en) * | 2001-09-03 | 2004-07-21 | 中国石油天然气股份有限公司 | Prepn of silica gel carrier |
| CN1278931C (en) * | 2002-12-30 | 2006-10-11 | 中国科学院化学研究所 | Process for continuously preparing meso visual ordered hybridization silicon dioxide fiber |
| CN1254876C (en) * | 2003-09-04 | 2006-05-03 | 张献国 | Method for making colloidal electrolyte |
| CN1288079C (en) * | 2004-02-17 | 2006-12-06 | 吉林市吉清科技开发有限公司 | Preparation method of microspherical silica used as alkene polymerization catalyst carrier |
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2005
- 2005-12-16 CN CNB2005101299651A patent/CN100436316C/en not_active Expired - Fee Related
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101829571A (en) * | 2010-06-08 | 2010-09-15 | 厦门大学 | Method for preparing Cu/SiO2 catalyst |
| CN102399330B (en) * | 2010-09-15 | 2013-07-31 | 中国石油天然气股份有限公司 | Preparation method of high-purity modified silica gel carrier |
| CN102399330A (en) * | 2010-09-15 | 2012-04-04 | 中国石油天然气股份有限公司 | Preparation method of high-purity modified silica gel carrier |
| 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 |
| 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 |
| 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 |
| CN102794202A (en) * | 2012-08-17 | 2012-11-28 | 垦利三合新材料科技有限责任公司 | Preparation method of aperture controllable catalyst carrier silicone |
| CN104650267A (en) * | 2013-11-19 | 2015-05-27 | 中国石油天然气股份有限公司 | Preparation method of double-peak pore-structure carrier silica gel |
| CN104650267B (en) * | 2013-11-19 | 2017-02-01 | 中国石油天然气股份有限公司 | Preparation method of double-peak pore-structure carrier silica gel |
| CN106477587A (en) * | 2015-08-25 | 2017-03-08 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN106477587B (en) * | 2015-08-25 | 2019-03-12 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN113248639A (en) * | 2021-06-01 | 2021-08-13 | 上海弘岸化工有限公司 | Silica gel supported polyolefin catalyst and preparation method and application thereof |
| CN113277680A (en) * | 2021-06-02 | 2021-08-20 | 渭南师范学院 | Method for treating heavy metal ions in chemical wastewater by using silicon dioxide |
| CN113583160A (en) * | 2021-09-14 | 2021-11-02 | 无锡玖汇科技有限公司 | Preparation method of composite carrier |
| CN113583159A (en) * | 2021-09-14 | 2021-11-02 | 无锡玖汇科技有限公司 | Supported polyolefin catalyst and preparation method thereof |
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