CN105111047A - Production method of Grade-99 pentaerythritol - Google Patents
Production method of Grade-99 pentaerythritol Download PDFInfo
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- CN105111047A CN105111047A CN201510538481.6A CN201510538481A CN105111047A CN 105111047 A CN105111047 A CN 105111047A CN 201510538481 A CN201510538481 A CN 201510538481A CN 105111047 A CN105111047 A CN 105111047A
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- grades
- pentaerythritol
- tetramethylolmethane
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- tower
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/36—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal
- C07C29/38—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal by reaction with aldehydes or ketones
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/78—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by condensation or crystallisation
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- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a production method of Grade-99 pentaerythritol. On the basis of the existing production technique of Grade-95 pentaerythritol, formaldehyde, acetaldehyde and liquid caustic soda are subjected to condensation reaction according to the set mole ratio through a DCS system in a tubular reactor, so the side reactions are fewer, and thus, the byproducts are fewer, thereby enhancing the content of the pentaerythritol. A triple-effect negative-pressure evaporation technique is utilized to evaporate the pentaerythritol, and monopentaerythritol and dipentaerythritol are separated by utilizing different solubilities of the pentaerythritol and byproduct at different temperatures and different characteristics of crystalline particles, thereby obtaining the pentaerythritol with the purity of up to 99%. By utilizing the heat energies of every link of the technique, the gas phase of the aldhyde removal tower of the hydrolysis tower is used as a pentaerythritol evaporation heat source, and the formaldehyde generated by the hydrolysis of the hydrolysis tower is recycled, thereby lowering the consumption of the raw material formaldehyde. The Grade-99 hydrolysis tower steam condensate is firstly used as a Grade-99 buffer tank heat source, and enters a Grade-99 mother solution decolorization tank to be used as thermal-insulation steam of the decolorization tank, thereby sufficiently saving the energy.
Description
Technical field
The present invention relates to Chemicals production field, specifically a kind of production method of 99 grades of tetramethylolmethanes.
Background technology
Tetramethylolmethane is a kind of important industrial chemicals, is widely used in the fields such as coating, medicine, agricultural chemicals.At present, produce in tetramethylolmethane process, mainly by condensation reaction principle, make condensing agent with sodium hydroxide, reaction formula is 4CH
2o+CH
3cHO+NaOH=C(CH
2oH)
4+ HCOONa, mixed solution in the condensated liquid generated after condensation reaction, except generating the methyl alcohol also generating dipentaerythritol, tripentaerythritol, many tetramethylolmethanes, tetramethylolmethane cyclic formals, sodium formiate, water and 35 ~ 40g/l formaldehyde and trace while tetramethylolmethane, this processing disadvantages is exactly that the condensation reaction material proportion fluctuation in process that feeds intake is large, by product is many, tetramethylolmethane content is low, does not still have a kind of highly purified Production of pentaerythritol method at present.
Summary of the invention
The object of the present invention is to provide a kind of production method of 99 grades of tetramethylolmethanes, should.
The technical solution adopted for the present invention to solve the technical problems is:
A production method for 99 grades of tetramethylolmethanes, comprises following steps:
A) 12 ~ 18% formaldehyde, 98% acetaldehyde and liquid caustic soda are carried out condensation reaction according to the charge ratio that mol ratio is 7.5 ︰ 1 ︰ 1.15 in tubular reactor, the temperature rise rate of reaction is 2 DEG C/5min, is incubated 10min, then neutralizes with formic acid after reaction 90min; Described charge ratio and temperature rise rate are all controlled automatically by DCS system;
B) condensated liquid is entered dealdehyder tower to get rid of 99.5% formaldehyde and send into tetramethylolmethane triple-effect evaporator after 55% water and be separated;
C) triple effect negative pressure evaporation technology is adopted to evaporate tetramethylolmethane, utilize dealdehyder tower tower top secondary steam as thermal source, the tetramethylolmethane mixed solution come from dealdehyder tower is evaporated to 110 DEG C, and proportion is enter medial launder heating after 1.35, enters 95 grades of crystallization kettles after being heated to 120 DEG C;
D) proportion is the tetramethylolmethane mixed solution naturally cooling of 1.35 after 1.5 hours by 95 grades of crystallization kettles, with the rate of temperature fall of 6 ~ 8 DEG C per hour cooling, centrifugal after cooling to 80 DEG C;
E) the centrifugal filter cake obtained washes rear feeding 99 grades of dissolving tanks with water, and washings returns triple-effect evaporator and reclaims, and mother liquor goes to prepare sodium formiate after 95 grades of subsiders filter;
F) 95 grades of filter cakes and 99 grades of mother liquors add 2 side's soft water and carry out proportioning at 99 grades of dissolving tanks by tetramethylolmethane content 70%; Proportioning liquid, at geosyncline phosphoric acid regulating ph value to 5, sends into 99 grades of dashpots after being warmed up to 97 DEG C, then by being pumped into 99 grades of hydrolysis towers;
G) temperature in 99 grades of hydrolysis towers control 125 DEG C, pressure is 3kg/m
2, feed rate is at 5m
3/ h, material is not less than 3 hours at 99 grades of hydrolysis dwell time in the tower;
H) discharging of 99 grades of hydrolysis towers enters continuous crystallizer, and the vacuum degree control of continuous crystallizer is at-55kPa, and temperature controls between 85 ~ 90 DEG C;
I) discharging of continuous crystallizer enters the insulation of centrifugal surge tank, and holding temperature controls at 85 ± 2 DEG C, and centrifugation time is 6 hours;
J) to make a gift to someone after the filter cake evaporation recycle-water washing after centrifugal drying shed drying, obtain 99 grades of tetramethylolmethane finished products;
K) centrifugal washing lotion directly enters the use of 99 grades of dashpot batchings, 99 grades of mother liquors after centrifugal enter 99 grades of mother liquor decolouring grooves, after 99 grades of mother liquor decolouring grooves add gac, again 99 grades of mother liquors are sent into 99 grades of clear liquid grooves, after clear liquid process, send into 99 grades of dashpots prepare burden, batching redundance sends into triple-effect evaporator.
The invention has the beneficial effects as follows, on the production technique basis of existing 95 grades of tetramethylolmethanes, in the condensation stage of tetramethylolmethane formation reaction, tubular reactor and DCS automated control technology is adopted to make condensation reaction side reaction under existing mol ratio minimum, thus improve the content of tetramethylolmethane, recycling tetramethylolmethane and by product at different temperatures different solubility and the different characteristic of crystalline particle carry out being separated in single, double season, thus obtain the tetramethylolmethane of high purity 99%; And make full use of the heat energy of each link of technique, hydrolysis tower is dropped a hint and is entered dealdehyder tower gas phase not only as tetramethylolmethane evaporation thermal source, but also the formaldehyde generated after having reclaimed hydrolysis tower hydrolysis, thus reduce the consumption of raw material formaldehyde; 99 grades of hydrolysis tower steam condensates, as entering 99 grades of mother liquor decolouring grooves after 99 grades of dashpot thermals source again, use as decolouring groove insulation steam, abundant save energy.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention is further described:
Fig. 1 is schematic flow sheet of the present invention.
Embodiment
As shown in Figure 1, the invention provides a kind of production method of 99 grades of tetramethylolmethanes, comprise the following steps:
A) 12 ~ 18% formaldehyde, 98% acetaldehyde and liquid caustic soda are carried out condensation reaction according to the charge ratio that mol ratio is 7.5 ︰ 1 ︰ 1.15 in tubular reactor, the temperature rise rate of reaction is 2 DEG C/5min, is incubated 10min, then neutralizes with formic acid after reaction 90min; Described charge ratio and temperature rise rate are all controlled automatically by DCS system, obtain the condensated liquid containing tetramethylolmethane, sodium formiate, water, formaldehyde, methyl alcohol;
B) condensated liquid enters dealdehyder tower after plate-type heat exchanger preheating, gets rid of 99.5% formaldehyde and sends into tetramethylolmethane triple-effect evaporator after 55% water again and be separated;
C) triple effect negative pressure evaporation technology is adopted to evaporate tetramethylolmethane, utilize dealdehyder tower tower top secondary steam as thermal source, the tetramethylolmethane mixed solution come from dealdehyder tower is evaporated to 110 DEG C, and proportion is enter medial launder heating after 1.35, enters 95 grades of crystallization kettles after being heated to 120 DEG C;
D) proportion is the tetramethylolmethane mixed solution naturally cooling of 1.35 after 1.5 hours by 95 grades of crystallization kettles, with the rate of temperature fall of 6 ~ 8 DEG C per hour cooling, centrifugal after cooling to 80 DEG C;
E) the centrifugal filter cake obtained washes rear feeding 99 grades of dissolving tanks with water, washings returns triple-effect evaporator and reclaims, mother liquor goes feeding 92 grades of crystallization kettles to obtain sodium formiate crystal after 95 grades of subsiders filter, and sodium formiate crystal sends into 92 grades of centrifuge, and centrifugal rear drying obtains sodium formiate finished product;
F) 95 grades of filter cakes 10 tons add 2 side's soft water with 2 tons, 99 grades of mother liquors and carry out proportioning at 99 grades of dissolving tanks by tetramethylolmethane content 70%; Proportioning liquid, at geosyncline phosphoric acid regulating ph value to 5, sends into 99 grades of dashpots after being warmed up to 97 DEG C, then by being pumped into 99 grades of hydrolysis towers;
G) temperature in 99 grades of hydrolysis towers control 125 DEG C, pressure is 3kg/m
2, feed rate is at 5m
3/ h, material is not less than 3 hours at 99 grades of hydrolysis dwell time in the tower;
H) discharging of 99 grades of hydrolysis towers enters continuous crystallizer, and the vacuum degree control of continuous crystallizer is at-55kPa, and temperature controls between 85 ~ 90 DEG C;
I) discharging of continuous crystallizer enters the insulation of centrifugal surge tank, and holding temperature controls at 85 ± 2 DEG C, and centrifugation time is 6 hours;
J) to make a gift to someone after the filter cake evaporation recycle-water washing after centrifugal drying shed drying, obtain 99 grades of tetramethylolmethane finished products, ash content 0.02%, moisture 0.2%, hydroxyl 49 colourity 1;
K) centrifugal washing lotion directly enters the use of 99 grades of dashpot batchings, 99 grades of mother liquors after centrifugal enter 99 grades of mother liquor decolouring grooves, after 99 grades of mother liquor decolouring grooves add gac, again 99 grades of mother liquors are sent into 99 grades of clear liquid grooves, after clear liquid process, send into 99 grades of dashpots prepare burden, batching redundance sends into triple-effect evaporator.
The tetramethylolmethane that the present invention obtains contrasts with the tetramethylolmethane content of traditional technology and sees the following form:
The present invention is in the condensation stage of tetramethylolmethane formation reaction, tubular reactor and DCS automated control technology is adopted to make condensation reaction side reaction under existing mol ratio minimum, thus improve the content of tetramethylolmethane, recycling tetramethylolmethane and by product at different temperatures different solubility and the different characteristic of crystalline particle carry out being separated in single, double season, thus obtain the tetramethylolmethane of high purity 99%; And make full use of the heat energy of each link of technique, hydrolysis tower is dropped a hint and is entered dealdehyder tower gas phase not only as tetramethylolmethane evaporation thermal source, but also the formaldehyde generated after having reclaimed hydrolysis tower hydrolysis, thus reduce the consumption of raw material formaldehyde; 99 grades of hydrolysis tower steam condensates, as entering 99 grades of mother liquor decolouring grooves after 99 grades of dashpot thermals source again, use as decolouring groove insulation steam, abundant save energy.
The above is only preferred embodiment of the present invention, not does any pro forma restriction to the present invention; Any those of ordinary skill in the art, do not departing under technical solution of the present invention ambit, the Method and Technology content of above-mentioned announcement all can be utilized to make many possible variations and modification to technical solution of the present invention, or be revised as the Equivalent embodiments of equivalent variations.Therefore, every content not departing from technical solution of the present invention, according to technical spirit of the present invention to any simple modification made for any of the above embodiments, equivalent replacement, equivalence change and modification, all still belongs in the scope of technical solution of the present invention protection.
Claims (1)
1. a production method for 99 grades of tetramethylolmethanes, is characterized in that, described method comprises following steps:
A) 12 ~ 18% formaldehyde, 98% acetaldehyde and liquid caustic soda are carried out condensation reaction according to the charge ratio that mol ratio is 7.5 ︰ 1 ︰ 1.15 in tubular reactor, the temperature rise rate of reaction is 2 DEG C/5min, is incubated 10min, then neutralizes with formic acid after reaction 90min; Described charge ratio and temperature rise rate are all controlled automatically by DCS system;
B) condensated liquid is entered dealdehyder tower to get rid of 99.5% formaldehyde and send into tetramethylolmethane triple-effect evaporator after 55% water and be separated;
C) triple effect negative pressure evaporation technology is adopted to evaporate tetramethylolmethane, utilize dealdehyder tower tower top secondary steam as thermal source, the tetramethylolmethane mixed solution come from dealdehyder tower is evaporated to 110 DEG C, and proportion is enter medial launder heating after 1.35, enters 95 grades of crystallization kettles after being heated to 120 DEG C;
D) proportion is the tetramethylolmethane mixed solution naturally cooling of 1.35 after 1.5 hours by 95 grades of crystallization kettles, with the rate of temperature fall of 6 ~ 8 DEG C per hour cooling, centrifugal after cooling to 80 DEG C;
E) the centrifugal filter cake obtained washes rear feeding 99 grades of dissolving tanks with water, and washings returns triple-effect evaporator and reclaims, and mother liquor goes to prepare sodium formiate after 95 grades of subsiders filter;
F) 95 grades of filter cakes and 99 grades of mother liquors add 2 side's soft water and carry out proportioning at 99 grades of dissolving tanks by tetramethylolmethane content 70%; Proportioning liquid, at geosyncline phosphoric acid regulating ph value to 5, sends into 99 grades of dashpots after being warmed up to 97 DEG C, then by being pumped into 99 grades of hydrolysis towers;
G) temperature in 99 grades of hydrolysis towers control 125 DEG C, pressure is 3kg/m
2, feed rate is at 5m
3/ h, material is not less than 3 hours at 99 grades of hydrolysis dwell time in the tower;
H) discharging of 99 grades of hydrolysis towers enters continuous crystallizer, and the vacuum degree control of continuous crystallizer is at-55kPa, and temperature controls between 85 ~ 90 DEG C;
I) discharging of continuous crystallizer enters the insulation of centrifugal surge tank, and holding temperature controls at 85 ± 2 DEG C, and centrifugation time is 6 hours;
J) to make a gift to someone after the filter cake evaporation recycle-water washing after centrifugal drying shed drying, obtain 99 grades of tetramethylolmethane finished products;
K) centrifugal washing lotion directly enters the use of 99 grades of dashpot batchings, 99 grades of mother liquors after centrifugal enter 99 grades of mother liquor decolouring grooves, after 99 grades of mother liquor decolouring grooves add gac, again 99 grades of mother liquors are sent into 99 grades of clear liquid grooves, after clear liquid process, send into 99 grades of dashpots prepare burden, batching redundance sends into triple-effect evaporator.
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| CN105111047B CN105111047B (en) | 2017-01-25 |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105693467A (en) * | 2016-04-06 | 2016-06-22 | 内蒙古宜化化工有限公司 | Energy-saving production method of pentaerythritol |
| CN109020782A (en) * | 2018-09-10 | 2018-12-18 | 武汉中能恒信工程技术有限公司 | A kind of preparation method of bulky grain pentaerythritol with co-production of formic acid potassium |
| CN109206297A (en) * | 2018-09-10 | 2019-01-15 | 武汉中能恒信工程技术有限公司 | A kind of preparation method of pentaerythritol with co-production sodium oxalate |
| CN109369347A (en) * | 2018-12-10 | 2019-02-22 | 安徽金禾实业股份有限公司 | A kind of preparation method of tripentaerythritol |
| CN109438182A (en) * | 2018-12-14 | 2019-03-08 | 赤峰瑞阳化工有限公司 | A kind of production system and its production technology of 99 grades of pentaerythrites |
| CN109503325A (en) * | 2018-12-10 | 2019-03-22 | 安徽金禾实业股份有限公司 | A kind of method that pentaerythrite reduces coloration |
| CN110790635A (en) * | 2019-11-19 | 2020-02-14 | 安徽金禾实业股份有限公司 | Multi-effect evaporation energy-saving method for pentaerythritol |
| CN112062659A (en) * | 2020-09-09 | 2020-12-11 | 赤峰瑞阳化工有限公司 | Method for producing tripentaerythritol with purity of more than 90 percent |
| CN115806473A (en) * | 2022-12-08 | 2023-03-17 | 赤峰瑞阳化工有限公司 | Method for removing pentaerythritol formal macromolecular impurities |
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| CN101696158A (en) * | 2009-09-30 | 2010-04-21 | 濮阳市鹏鑫化工有限公司 | Method for preparing pentaerythritol and dipentaerythritol |
| CN202226794U (en) * | 2011-10-12 | 2012-05-23 | 贵州金江化工有限公司 | High-purity pentaerythritol purification device |
| CN103113191A (en) * | 2012-11-11 | 2013-05-22 | 安徽金禾实业股份有限公司 | Method for producing pentaerythritol by removing formaldehyde through double rectification column |
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2015
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Patent Citations (3)
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| CN101696158A (en) * | 2009-09-30 | 2010-04-21 | 濮阳市鹏鑫化工有限公司 | Method for preparing pentaerythritol and dipentaerythritol |
| CN202226794U (en) * | 2011-10-12 | 2012-05-23 | 贵州金江化工有限公司 | High-purity pentaerythritol purification device |
| CN103113191A (en) * | 2012-11-11 | 2013-05-22 | 安徽金禾实业股份有限公司 | Method for producing pentaerythritol by removing formaldehyde through double rectification column |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105693467A (en) * | 2016-04-06 | 2016-06-22 | 内蒙古宜化化工有限公司 | Energy-saving production method of pentaerythritol |
| CN105693467B (en) * | 2016-04-06 | 2018-02-09 | 内蒙古宜化化工有限公司 | A kind of pentaerythrite energy-saving production method |
| CN109020782A (en) * | 2018-09-10 | 2018-12-18 | 武汉中能恒信工程技术有限公司 | A kind of preparation method of bulky grain pentaerythritol with co-production of formic acid potassium |
| CN109206297A (en) * | 2018-09-10 | 2019-01-15 | 武汉中能恒信工程技术有限公司 | A kind of preparation method of pentaerythritol with co-production sodium oxalate |
| CN109020782B (en) * | 2018-09-10 | 2021-11-19 | 武汉中能恒信工程技术有限公司 | Preparation method of large-particle pentaerythritol and potassium formate |
| CN109503325A (en) * | 2018-12-10 | 2019-03-22 | 安徽金禾实业股份有限公司 | A kind of method that pentaerythrite reduces coloration |
| CN109369347A (en) * | 2018-12-10 | 2019-02-22 | 安徽金禾实业股份有限公司 | A kind of preparation method of tripentaerythritol |
| CN109503325B (en) * | 2018-12-10 | 2021-12-21 | 安徽金禾实业股份有限公司 | Method for reducing chroma of pentaerythritol |
| CN109438182A (en) * | 2018-12-14 | 2019-03-08 | 赤峰瑞阳化工有限公司 | A kind of production system and its production technology of 99 grades of pentaerythrites |
| CN109438182B (en) * | 2018-12-14 | 2021-04-27 | 赤峰瑞阳化工有限公司 | Production system and production process of 99-grade pentaerythritol |
| CN110790635A (en) * | 2019-11-19 | 2020-02-14 | 安徽金禾实业股份有限公司 | Multi-effect evaporation energy-saving method for pentaerythritol |
| CN112062659A (en) * | 2020-09-09 | 2020-12-11 | 赤峰瑞阳化工有限公司 | Method for producing tripentaerythritol with purity of more than 90 percent |
| CN112062659B (en) * | 2020-09-09 | 2023-04-07 | 赤峰瑞阳化工有限公司 | Method for producing tripentaerythritol with purity of more than 90 percent |
| CN115806473A (en) * | 2022-12-08 | 2023-03-17 | 赤峰瑞阳化工有限公司 | Method for removing pentaerythritol formal macromolecular impurities |
| CN115806473B (en) * | 2022-12-08 | 2023-09-12 | 赤峰瑞阳化工有限公司 | Method for removing macromolecular impurities of pentaerythritol formal |
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| CN105111047B (en) | 2017-01-25 |
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