CN112717874A - Novel reaming manufacturing method of macroporous silica gel - Google Patents
Novel reaming manufacturing method of macroporous silica gel Download PDFInfo
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- CN112717874A CN112717874A CN202011442499.3A CN202011442499A CN112717874A CN 112717874 A CN112717874 A CN 112717874A CN 202011442499 A CN202011442499 A CN 202011442499A CN 112717874 A CN112717874 A CN 112717874A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
- B01J20/103—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate comprising silica
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28078—Pore diameter
- B01J20/28085—Pore diameter being more than 50 nm, i.e. macropores
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Abstract
The invention discloses a novel reaming manufacturing method of macroporous silica gel, which relates to the technical field of production and preparation of massive silica gel, and solves the problems of low automation level, high labor intensity, poor working environment, difficulty in scale production, low production efficiency and the like in the existing production process of macroporous silica gel in the prior art, and the following scheme is proposed: the preparation method comprises the steps of carrying out low-temperature gel preparation by using dilute sulfuric acid and sodium silicate as raw materials to obtain a reaction material, carrying out aging in an aging tank for the first reaming to obtain an aging material, and carrying out gel tapping crushing on the aging material by adopting low-crushing equipment to obtain a gel tapping material. The macroporous massive silica gel produced by the method has the characteristics of uniform product granularity, stable pore volume and pore diameter and high purity of silicon dioxide, is low in production cost, economical and environment-friendly, is easy to realize large-scale industrial production, and has good popularization significance.
Description
Technical Field
The invention relates to the technical field of production and preparation of massive silica gel, in particular to a novel reaming manufacturing method of macroporous silica gel.
Background
The silica gel has the alias: the silicic acid gel is a high-activity adsorption material and belongs to an amorphous substance. The main component of the silica gel is silicon dioxide, and the silica gel is stable in chemical property and does not burn.
The existing macroporous silica gel production process has the characteristics of low automation level, high labor intensity, poor working environment, difficulty in scale production or low production efficiency, higher production cost, lower product pore volume, low controllability of product performance indexes, larger unexpected process change influence and the like. And the production line has high environmental treatment cost and is difficult to realize scale benefit. The production reaming of the macroporous silica gel adopts steam or high-temperature hot water reaming or salt leaching reaming, and the product has the defects of low yield of main products, large crushing, more powder, low product strength, low catalytic activity and the like. And the defects of high production cost, complex process control and the like of the macroporous silica gel produced by adopting organic silicon and an organic pore-expanding agent as raw materials are also overcome.
Disclosure of Invention
The invention aims to solve the technical problems that the existing macroporous silica gel production process in the prior art has the characteristics of low automation level, high labor intensity, poor working environment, difficulty in scale production or low production efficiency, higher production cost, lower product pore volume, low controllability of product performance indexes, larger unexpected process change influence and the like. And the production line has high environmental treatment cost and is difficult to realize scale benefit. The production reaming of the macroporous silica gel adopts steam or high-temperature hot water reaming or salt leaching reaming, and the product has the defects of low yield of main products, large crushing, more powder, low product strength, low catalytic activity and the like. In addition, the method for manufacturing the macroporous silica gel adopts organosilicon and organic pore-expanding agent as raw materials, has the defects of high production cost, complex process control and the like, and aims to solve the technical problem, the novel method for manufacturing the macroporous silica gel is provided, the method uses dilute sulfuric acid and sodium silicate as raw materials to carry out low-temperature gel-making to obtain a reaction material, the reaction material is aged in an aging tank for the first time to carry out pore-expanding to obtain an aging material, the aging material is subjected to gel tapping crushing by adopting low-crushing equipment to obtain a gel tapping material, the gel tapping material enters a serial washing water tank and is subjected to countercurrent washing by spraying condensed water to clean sodium sulfate, sulfuric acid and metal ion impurities generated in the gel-making reaction process, the next water tank after the serial washing of the initial water tank is finished is used as the serial washing water tank to carry out serial washing, the silica gel in the serial washing water tank is subjected to secondary pore-expanding by adopting a pore-, after reaming, the mixture is conveyed to a multi-layer mesh belt steam drying device through an automatic glue scooping machine to obtain low-moisture massive silica gel for screening and separation, and macroporous massive silica gel with different particle size specifications is obtained.
Preferably, a dilute sulfuric acid and sodium silicate raw material pump is automatically started, the temperature of the dilute sulfuric acid and the temperature of the sodium silicate are controlled to be 15-20 ℃, so that stable low-temperature glue making reaction is realized, the concentration of the dilute sulfuric acid is 20-25%, the concentration of the sodium silicate is 25-30%, and the modulus of the sodium silicate is 3.2-3.4.
Preferably, the low-temperature glue-making reaction material enters a rail-type or chain-type aging tank, the aging tank is automatically driven by a motor, the rotating speed frequency of the motor is controlled, the low-temperature glue-making reaction material is automatically received, and the aging time of the reaction material in the aging tank is 30-40 hours to obtain the aging material.
Preferably, the aging material is subjected to tapping by adopting low-crushing equipment through controlling the rotating speed of a motor through frequency conversion to obtain a tapping material, tapping water is from spray hot water, and the breakage equipment adopts a sawtooth type or double-roll type rotating wheel.
Preferably, the countercurrent washing hot water is hot water obtained by spraying the drying tail gas, the countercurrent washing water washing tanks adopt circulating gradient serial washing, the number of the serial washing tanks is 6-9, and the temperature of the hot water is 50-60 ℃.
Preferably, the pore-expanding agent is an inorganic substance which is ammonia water or ammonium bicarbonate or ammonium carbonate, the mass concentration of the inorganic substance is 0.1-0.3%, the temperature of the pore-expanding agent is 65-75 ℃, the pore-expanding time is 6-10 h, and the pore-expanding agent is recycled.
Preferably, the glue scooping machine is provided with a filter screen, and the glue scooping machine which scoops the glue and bundles the glue through the filter screen is filtered by a plate frame to obtain hot water containing the pore-expanding agent for pore-expanding.
Preferably, the drying equipment is continuous multi-layer mesh belt steam drying equipment, the drying temperature is 100-160 ℃, the steam pressure is 0.55-0.65 MPa, and steam condensate water is recycled.
Preferably, the drying tail gas generated by the drying equipment adopts a multilayer tower plate type efficient spray tower to recover condensed water, the efficient spray tower is provided with a circulating spray to improve the waste heat recovery efficiency and recover hot water and a pore-expanding agent, and the efficient dust removal is achieved
Preferably, the screening equipment used for screening separation is a linear vibrating screen.
Preferably, the silica gel packaging equipment comprises automatic weighing, automatic bag sewing and automatic stacking.
Compared with the prior art, the invention has the beneficial effects that:
1. the automatic production line has simple process flow and is easy for industrial popularization.
2. The hole expanding agent is recycled, and hole expansion is stabilized step by step.
3. The product quality is controllable, the waste heat is comprehensively utilized, and the production cost is low.
4. The screening equipment used for screening and separating is a linear vibrating screen, has the characteristics of small damage and small abrasion, and can obtain products with uniform granularity and high granularity qualification rate through multi-stage screening.
The macroporous massive silica gel produced by the method has the characteristics of uniform product granularity, stable pore volume and pore diameter and high purity of silicon dioxide, is low in production cost, economical and environment-friendly, is easy to realize large-scale industrial production, and has good popularization significance.
Drawings
FIG. 1 is a flow chart of a process for manufacturing silica gel according to the present invention.
Detailed Description
The invention is further described with reference to the accompanying drawings and examples.
In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "vertical", "horizontal", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used for convenience of description only, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
Referring to fig. 1, a novel reaming manufacturing method of macroporous silica gel, the manufacturing method comprises the steps of using dilute sulfuric acid and sodium silicate as raw materials to prepare a reaction material by low-temperature gel making, aging the reaction material in an aging tank for the first reaming to obtain an aging material, using low-crushing equipment to perform gel tapping crushing to obtain a gel cutting material, using spray condensate water to perform countercurrent washing in a washing tank to clean sodium sulfate, sulfuric acid and metal ion impurities generated in the gel making reaction process, using a next washing tank as an initial washing tank to perform serial washing after the serial washing of the initial washing tank is finished, using gel fishing return water to prepare a pore-expanding agent with a certain concentration and temperature to perform secondary reaming, using an automatic gel fishing machine to convey the gel to a multi-layer mesh-belt block steam drying equipment after the reaming is finished, obtaining low-moisture silica gel to perform screening separation, obtaining macroporous massive silica gel with different grain size specifications.
In order to better manufacture the silica gel, the invention also comprises a raw material pump for automatically starting the dilute sulfuric acid and the sodium silicate, wherein the temperature of the dilute sulfuric acid and the sodium silicate is controlled to be 15-20 ℃ so as to realize the stable low-temperature gel-making reaction, the concentration of the dilute sulfuric acid is 20-25%, the concentration of the sodium silicate is 25-30%, and the modulus of the sodium silicate is 3.2-3.4. And the low-temperature glue-making reaction material enters a rail-type or chain-type aging tank, the aging tank is automatically driven by a motor, the rotating speed frequency of the motor is controlled, the low-temperature glue-making reaction material is automatically received, and the aging time of the reaction material in the aging tank is 30-40 hours to obtain the aging material. The aging material is subjected to tapping by adopting low-crushing equipment through controlling the rotating speed of a motor through frequency conversion to obtain a tapping material, tapping water is from spray hot water, and the breakage equipment adopts a sawtooth type or double-roller type rotating wheel. The countercurrent washing hot water is hot water obtained by spraying dried tail gas, and the countercurrent washing water washing tanks adopt circulating gradient serial washing, the number of the serial washing tanks is 6-9, and the temperature of the hot water is 50-60 ℃. The pore-expanding agent is an inorganic substance which is ammonia water, ammonium bicarbonate or ammonium carbonate, the mass concentration of the inorganic substance is 0.1-0.3%, the temperature of the pore-expanding agent is 65-75 ℃, the pore-expanding time is 6-10 hours, and the pore-expanding agent is recycled. The glue scooping machine is provided with a filter screen, and the glue scooping machine which scoops the glued and bound glue and penetrates through the filter screen is filtered by the plate frame to obtain hot water containing the pore-expanding agent for pore-expanding. The drying equipment is continuous multi-layer mesh belt steam drying equipment, the drying temperature is 100-160 ℃, the steam pressure is 0.55-0.65 MPa, and steam condensate water is recycled. Drying tail gas that drying equipment produced adopts multilayer tower plate formula high efficiency spray column to retrieve the comdenstion water, and high efficiency spray column is equipped with the circulation and sprays and improve waste heat recovery efficiency and retrieve hot water and reaming agent to it is the linear vibrating screen to reach the screening installation that high efficiency dust removal screening separation used. The silica gel packaging equipment comprises automatic weighing, automatic bag sewing and automatic stacking.
The working principle is as follows: preparing dilute sulfuric acid with the mass concentration of 18 percent at the temperature of 20 ℃, performing low-temperature glue-making reaction with sodium silicate with the mass concentration of 26 percent at the temperature of 20 ℃ to a chain type aging tank, standing and aging the reaction material in the aging tank for 36h for carrying out first hole expansion, then performing glue cutting by using a roller type crushing device, then performing countercurrent washing by using hot water subjected to spray condensation at the temperature of 55 ℃, then preparing 0.15 percent mass concentration by using glue fishing backwater and steam condensate water, soaking in 70 ℃ ammonia water for 6h for carrying out second hole expansion, conveying to a multi-layer mesh belt steam drying device by using an automatic glue fishing machine after hole expansion is completed, setting the temperature of a first layer of mesh belt to be 100-140 ℃, setting the temperature of a second layer of mesh belt to be 140-160 ℃, setting the temperature of a third layer of mesh belt device to be 100-160 ℃, obtaining silica gel with the moisture content of less than or equal to 5, 1-6mm, 0.5-2 mm, and powder.
The above-described embodiments only express the preferred embodiments of the present invention, and the description thereof is more specific and detailed, but the present invention is not limited to these embodiments, and it should be noted that it is obvious to those skilled in the art. Any modification falling within the scope of protection of the present invention without departing from the gist of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (11)
1. A novel reaming manufacturing method of macroporous silica gel is characterized in that: the manufacturing method comprises the steps of carrying out low-temperature gel making by taking dilute sulfuric acid and sodium silicate as raw materials to obtain a reaction material, carrying out aging first-time chambering on the reaction material in an aging tank to obtain an aging material, carrying out gel tapping crushing on the aging material by adopting low-crushing equipment to obtain a gel tapping material, enabling the gel tapping material to enter a serial washing tank, washing sodium sulfate, sulfuric acid and metal ion impurities generated in the gel making reaction process by adopting spray condensate water to carry out countercurrent washing by adopting spray condensate water, carrying out serial washing by taking the next washing tank as an initial washing tank after the serial washing of the initial washing tank is finished, carrying out secondary chambering expansion on silica gel in the serial washing tank by adopting gel fishing return water to prepare a pore expanding agent with certain concentration and temperature, and carrying out screening separation on the obtained low-moisture blocky silica gel by adopting an automatic glue fishing machine after the chambering expansion is finished, thereby obtaining the.
2. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: and (3) automatically starting a dilute sulfuric acid and sodium silicate raw material pump, controlling the temperature of the dilute sulfuric acid and the sodium silicate to be 15-20 ℃ so as to realize stable low-temperature glue making reaction, wherein the concentration of the dilute sulfuric acid is 20-25%, the concentration of the sodium silicate is 25-30%, and the modulus of the sodium silicate is 3.2-3.4.
3. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 2, characterized in that: and the low-temperature glue-making reaction material enters a rail-type or chain-type aging tank, the aging tank is automatically driven by a motor, the rotating speed frequency of the motor is controlled, the low-temperature glue-making reaction material is automatically received, and the aging time of the reaction material in the aging tank is 30-40 hours to obtain the aging material.
4. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the aging material is subjected to tapping by adopting low-crushing equipment through controlling the rotating speed of a motor through frequency conversion to obtain a tapping material, tapping water is from spray hot water, and the breakage equipment adopts a sawtooth type or double-roller type rotating wheel.
5. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the countercurrent washing hot water is hot water obtained by spraying dried tail gas, and the countercurrent washing water washing tanks adopt circulating gradient serial washing, the number of the serial washing tanks is 6-9, and the temperature of the hot water is 50-60 ℃.
6. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the pore-expanding agent is an inorganic substance which is ammonia water, ammonium bicarbonate or ammonium carbonate, the mass concentration of the inorganic substance is 0.1-0.3%, the temperature of the pore-expanding agent is 65-75 ℃, the pore-expanding time is 6-10 hours, and the pore-expanding agent is recycled.
7. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the glue scooping machine is provided with a filter screen, and the glue scooping machine which scoops the glued and bound glue and penetrates through the filter screen is filtered by the plate frame to obtain hot water containing the pore-expanding agent for pore-expanding.
8. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the drying equipment is continuous multi-layer mesh belt steam drying equipment, the drying temperature is 100-160 ℃, the steam pressure is 0.55-0.65 MPa, and steam condensate water is recycled.
9. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: drying tail gas that drying equipment produced adopts multilayer tower plate formula high efficiency spray column to retrieve the comdenstion water, and high efficiency spray column is equipped with the circulation and sprays and improve waste heat recovery efficiency and retrieve hot water and reaming agent to reach high-efficient dust removal.
10. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the screening equipment used for screening and separating is a linear vibrating screen.
11. The novel broaching manufacturing method of macroporous silica gel as claimed in claim 1, characterized in that: the silica gel packaging equipment comprises automatic weighing, automatic bag sewing and automatic stacking.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310437526.5A CN116459784A (en) | 2020-12-08 | 2020-12-08 | Novel macroporous silica gel reaming manufacturing method based on cyclic utilization of reaming agent |
| CN202011442499.3A CN112717874A (en) | 2020-12-08 | 2020-12-08 | Novel reaming manufacturing method of macroporous silica gel |
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| CN202011442499.3A CN112717874A (en) | 2020-12-08 | 2020-12-08 | Novel reaming manufacturing method of macroporous silica gel |
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| CN202310437526.5A Division CN116459784A (en) | 2020-12-08 | 2020-12-08 | Novel macroporous silica gel reaming manufacturing method based on cyclic utilization of reaming agent |
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| CN112717874A true CN112717874A (en) | 2021-04-30 |
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| CN202011442499.3A Pending CN112717874A (en) | 2020-12-08 | 2020-12-08 | Novel reaming manufacturing method of macroporous silica gel |
| CN202310437526.5A Pending CN116459784A (en) | 2020-12-08 | 2020-12-08 | Novel macroporous silica gel reaming manufacturing method based on cyclic utilization of reaming agent |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3501269A (en) * | 1967-04-20 | 1970-03-17 | Grace W R & Co | Process for preparing silica gel |
| CN1363514A (en) * | 2001-01-11 | 2002-08-14 | 青岛美晶化工有限公司 | macroreticular silica gel and its preparing process |
| CN101591022A (en) * | 2009-06-29 | 2009-12-02 | 青岛中能集团有限公司 | A kind of preparation process of high-purity silica gel and method |
| CN104229810A (en) * | 2013-06-20 | 2014-12-24 | 青岛康威龙日用品有限公司 | Preparation method of coarse-pore blocky silica gel |
| CN105776227A (en) * | 2014-12-13 | 2016-07-20 | 王欣欣 | Production technology of ultra-large-pore adsorptive silica gels |
| CN109292784A (en) * | 2018-10-25 | 2019-02-01 | 青岛美高集团有限公司 | A kind of preparation method of silica gel and thus resulting silica gel |
| CN209735560U (en) * | 2019-03-13 | 2019-12-06 | 青岛创客机械设备制造有限公司 | Full-automatic glue making device |
-
2020
- 2020-12-08 CN CN202011442499.3A patent/CN112717874A/en active Pending
- 2020-12-08 CN CN202310437526.5A patent/CN116459784A/en active Pending
Patent Citations (7)
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|---|---|---|---|---|
| US3501269A (en) * | 1967-04-20 | 1970-03-17 | Grace W R & Co | Process for preparing silica gel |
| CN1363514A (en) * | 2001-01-11 | 2002-08-14 | 青岛美晶化工有限公司 | macroreticular silica gel and its preparing process |
| CN101591022A (en) * | 2009-06-29 | 2009-12-02 | 青岛中能集团有限公司 | A kind of preparation process of high-purity silica gel and method |
| CN104229810A (en) * | 2013-06-20 | 2014-12-24 | 青岛康威龙日用品有限公司 | Preparation method of coarse-pore blocky silica gel |
| CN105776227A (en) * | 2014-12-13 | 2016-07-20 | 王欣欣 | Production technology of ultra-large-pore adsorptive silica gels |
| CN109292784A (en) * | 2018-10-25 | 2019-02-01 | 青岛美高集团有限公司 | A kind of preparation method of silica gel and thus resulting silica gel |
| CN209735560U (en) * | 2019-03-13 | 2019-12-06 | 青岛创客机械设备制造有限公司 | Full-automatic glue making device |
Non-Patent Citations (2)
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| 王文静 等, 中国海洋大学出版社 * |
| 王海 等: "催化剂载体硅胶的扩孔研究进展", 《甘肃化工》 * |
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