CN102887959A - Method for synthesizing cationic guar gum by mixed solvent method - Google Patents
Method for synthesizing cationic guar gum by mixed solvent method Download PDFInfo
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Abstract
The invention relates to a mixed solvent method for synthesizing cationic guar gum. According to the method, water and isopropanol in a certain proportion are used as a mixed solvent, and guar gum, alkali and a cation reagent can uniformly and highly efficiently react in the mixed solvent. The reaction requires a mild condition and is easy to operate, and it is simple to refine. A synthesized cationic guar gum crude product undergoes processes of filtration, washing, drying and the like to remove impurities so as to obtain the cationic guar gum with its effective content being greater than or equal to 90%, viscosity (1% of an aqueous solution) being greater than or equal to 3500 mpa.s and nitrogen content being greater than or equal to 0.4%.
Description
Technical field
The present invention relates to a kind of synthetic method of cation guar gum, especially a kind of method with mixed solvent method synthesizing cationic guar gum belongs to the field of chemical synthesis.
Background technology
Cation guar gum is widely used in the fields such as papermaking, oilfield additive, cosmetic material as important auxiliary chemicals.
The at present preparation of cation guar gum mainly is to react with cationic etherifying agent under the effect of sodium hydroxide by the guar gum raw material, generates cation guar gum.Reaction formula is:
It seems from the preparation method of in the past cation guar gum, according to the difference of reaction medium, the preparation method is divided into: organic solvent method, water solvent method, dry method.Organic solvent method is with a large amount of water-miscible organic solvents (ethanol, methyl alcohol, Virahol), guar gum is dispersed in wherein forms pulpous state, and react the method for preparing cation guar gum with cationic reagent.This kind method is used a large amount of organic solvent costs and is greatly improved, and required reactor is very large, needs simultaneously a large amount of salt, is difficult to suitability for industrialized production.The water solvent method is guar gum raw material and water heated and stirred to be made become pasty state, and then obtains cation guar gum with alkali and cationoid reagent reaction.Because guar gum is easy gel in water, this kind method can only prepare the cation guar gum of low degree of substitution.And need very long gelatinization time and reaction times, be unfavorable for industrial production.Dry method is that the mixture with alkali lye and cationoid reagent is sprayed onto on the former powder of guar gum, get final product in 1～2 hour 60～80 ℃ of lower stirrings, and the method is easy and simple to handle, but stirs inhomogeneous, reaction not exclusively, the very high reason of equipment requirements is difficult to application.
Summary of the invention
The object of the invention is to, a certain proportion of mixed solvent is provided, make even, efficient, economic the carrying out of cation modifying of guar gum.
Method with mixed solvent method synthesizing cationic guar gum of the present invention follows these steps to carry out:
A, the mass ratio of pressing guar gum and sodium hydroxide (the certain density aqueous solution) and isopropanol solvent are=1:0.2～0.25:0.2～0.3, join in the reactor, stir.
B, maintenance solution temperature are 40～60 ℃, to wherein adding the cationic etherifying agent aqueous solution (CTA), the mass ratio of cationic etherifying agent and guar gum=0.3～0.5.Added complete rear stirring reaction 4～6 hours.
After c, reaction finished, the PH that adds the hydrochloric acid soln regulator solution in the reaction mixture was 7, and filtering separation obtains the crude product of cation guar gum, and crude product enters that next step is refining.
D, with a certain amount of distilled water wash of crude product, the mass ratio of distilled water and crude product is 0.1:1.Use the washed with isopropyl alcohol crude product three times, the mass ratio of each Virahol and crude product is 0.1:1 again.After filtering filter cake is put in 60 ℃ the baking oven dry 1 hour.Cation guar gum after must making with extra care.Wherein substitution value is 1.8, and viscosity is 3200PaS above (0.5% the aqueous solution).
Wherein the mass concentration of the aqueous sodium hydroxide solution among the step a is 20%～30%, and the mass concentration of the cationic etherifying agent aqueous solution among the step b is 69%.
The mixed solvent of water and Virahol is as reaction medium in the process of reaction, and wherein water comes from sodium hydroxide solution and cationic etherifying agent solution, and the mass ratio of water and Virahol is 3～4:1.
Beneficial effect
Reaction conditions of the present invention is gentle, is easy to control, and the impurity that produces in the reaction is dissolved in the mixing solutions, and filtration can be removed, and has simplified purification step.Characteristics of the present invention are: the characteristics that the reaction times is short, selectivity is high, productive rate is high, product purity is high, energy consumption is low, consumption of organic solvent is few.
Embodiment
The present invention can according to the technology implementation in the summary of the invention, further specify embodiment with following indefiniteness embodiment.
Embodiment 1
In the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, add 200g guar gum raw material, be 25% NaOH solution and 80g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3500mpas; Nitrogen content 0.45%; Active matter content 90%.
Embodiment 2
In the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, add 200g guar gum raw material, be 25% NaOH solution and 150g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3540mpas; Nitrogen content 0.47%; Active matter content 91%.
Embodiment 3
In the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, add 200g guar gum raw material, be 20% NaOH solution and 80g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3470mpas; Nitrogen content 0.42%; Active matter content 86%.
Embodiment 4
Adding 200g guar gum raw material in the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, is 25% NaOH solution to wherein adding the 176g massfraction again, under agitation is heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3100mpas; Nitrogen content 0.34%; Active matter content 81%.
Embodiment 5
Adding 200g guar gum raw material in the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, is 25% NaOH solution and 80g distilled water to wherein adding the 176g massfraction again, under agitation is heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3110mpas; Nitrogen content 0.35%; Active matter content 83%.
Embodiment 6
In the beaker of the four-hole 500ml that thermometer, reflux condensing tube, dropping funnel and agitator are housed, add 200g guar gum raw material, again to wherein adding the 800g isopropanol solvent, under agitation be heated to 60 ℃ of reaction 1h.This moment, reaction system was mixed uniformly mashed prod, and adding the 88g massfraction in the reaction system by dropping funnel is that 50% NaOH solution and 107g working substance content are 69% the cationic etherifying agent aqueous solution (CTA), keeps 60 ℃ to react 4h.The temperature of question response liquid is down to room temperature, adds the PH to 7 of a certain amount of HCl solution conditioned reaction mixture.Filter reaction mixture, filter cake washs in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dries with 10ml distilled water wash twice, and obtain flaxen solid product: viscosity (25 ℃ of 1% aqueous solution) is 3600mpas; Nitrogen content 0.48%; Active matter content 94%.
The present invention with an organic solvent with the method for water as mixed solvent, organic solvent can promote the good pulp of guar gum raw material, improves reaction yield, Reaction time shorten, reduction temperature of reaction, dissolving part organic impurity.The while water solvent can well dissolve and remove inorganic impurity (NaCl), replace a part of organic solvent to reduce cost, to reduce potential safety hazard, reduction aftertreatment cost in producing as eco-friendly solvent.
Mixed solvent method and organic solvent method contrast: the usage quantity that 1) greatly reduces organic solvent has been saved cost; 2) reduced the potential safety hazard of actual production, ethanol, methyl alcohol, Virahol be as easy volatile solvent, evaporate in the air not only dangerously but also can bring actual bodily harm to producers, uses mixed solvent can greatly reduce the volatilization of solvent; 3) can be except the NaCl that produces in the dereaction, NaCl can not be dissolved in the organic reagent as inorganic salt, only uses organic reagent to bring difficulty to separation.The contrast of mixed solvent and water solvent: 1) increased gelatinization speed and the gelatinization effect of guar gum, make reaction can be more even, carry out more efficiently; 2) can dissolve the unreacted organism of part and organic impurity, improve the purity of product.
The contrast of mixed solvent method and dry method: 1) simple to operate, to equipment require low; 2) sufficient reacting, the product substitution value is high; 3) NaCl and a small amount of organic impurity mixed solvent that produce in the reaction process can be left in the dry method and then these impurity can be well dissolved and in filtration, remove.Utilize in sum mixed solvent method to prepare cation guar gum and can make building-up reactions evenly, carry out efficiently, reduced the consumption of organic solvent, be easy to the industrialization operation.
Claims (9)
1. with the method for mixed solvent method synthesizing cationic guar gum, it is characterized in that synthesizing according to the following steps: a, the mass ratio of press guar gum and aqueous sodium hydroxide solution and isopropanol solvent be=1:0.2～0.25:0.2～0.3, joins in the reactor, stirs; B, maintenance solution temperature are 40～60 ℃, and to wherein adding the cationic etherifying agent aqueous solution, the mass ratio of cationic etherifying agent and guar gum=0.3～0.5 added complete rear stirring reaction 4～6 hours; After c, reaction finished, the PH that adds the hydrochloric acid soln regulator solution in the reaction mixture was 7, and filtering separation obtains the crude product of cation guar gum, and crude product enters that next step is refining; D, with a certain amount of distilled water wash of crude product, the mass ratio of distilled water and crude product is 0.1:1, use again the washed with isopropyl alcohol crude product three times, the mass ratio of each Virahol and crude product is 0.1:1, after filtering filter cake is put in 60 ℃ the baking oven dry 1 hour, cation guar gum after must making with extra care, wherein substitution value is 1.8, viscosity is more than the 3200PaS.
2. the method with mixed solvent method synthesizing cationic guar gum according to claim 1 is characterized in that, the mass concentration of the aqueous sodium hydroxide solution in step a is 20%～30%, and the mass concentration of the cationic etherifying agent aqueous solution among the step b is 69%.
3. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, the mixed solvent of water and Virahol is as reaction medium in the process of reaction, wherein water comes from sodium hydroxide solution and cationic etherifying agent solution, and the mass ratio of water and Virahol is 3～4:1.
4. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, be 25% NaOH solution and 80g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3500mpas; Nitrogen content 0.45%; Active matter content 90%.
5. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, be 25% NaOH solution and 150g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3540mpas; Nitrogen content 0.47%; Active matter content 91%.
6. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, be 20% NaOH solution and 80g isopropanol solvent to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3470mpas; Nitrogen content 0.42%; Active matter content 86%.
7. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, be 25% NaOH solution to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3100mpas; Nitrogen content 0.34%; Active matter content 81%.
8. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, be 25% NaOH solution and 80g distilled water to wherein adding the 176g massfraction again, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding 107g working substance content in the reaction system by dropping funnel is 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3110mpas; Nitrogen content 0.35%; Active matter content 83%.
9. the method with mixed solvent method synthesizing cationic guar gum according to claim 1, it is characterized in that, thermometer is being housed, reflux condensing tube, add 200g guar gum raw material in the beaker of the four-hole 500ml of dropping funnel and agitator, again to wherein adding the 800g isopropanol solvent, under agitation be heated to 60 ℃ of reaction 1h, this moment, reaction system was mixed uniformly mashed prod, adding the 88g massfraction in the reaction system by dropping funnel is that 50% NaOH solution and 107g working substance content are 69% the cationic etherifying agent aqueous solution, keep 60 ℃ of reaction 4h, the temperature of question response liquid is down to room temperature, the PH to 7 that adds a certain amount of HCl solution conditioned reaction mixture, filter reaction mixture, twice of 10ml distilled water wash of filter cake, wash in the baking oven of sending into 80 ℃ after three times with the 10ml isopropanol solvent and dry, obtain flaxen solid product: viscosity is 3600mpas; Nitrogen content 0.48%; Active matter content 94%.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20010051143A1 (en) * | 1999-04-26 | 2001-12-13 | Ian W. Cottrell | Keratin treating cosmetic compositions containing high ds cationic guar gum derivatives |
| CN101077892A (en) * | 2007-06-28 | 2007-11-28 | 上海东升新材料有限公司 | Cation guar gum and preparing process thereof |
| CN101563367A (en) * | 2006-11-17 | 2009-10-21 | 蓝宝迪有限公司 | Procedure for the preparation of purified cationic guar |
| CN101768225A (en) * | 2010-02-10 | 2010-07-07 | 刘东辉 | Cation guar gum with transparent gum liquid and preparation method thereof |
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2011
- 2011-07-19 CN CN2011102017709A patent/CN102887959A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20010051143A1 (en) * | 1999-04-26 | 2001-12-13 | Ian W. Cottrell | Keratin treating cosmetic compositions containing high ds cationic guar gum derivatives |
| CN101563367A (en) * | 2006-11-17 | 2009-10-21 | 蓝宝迪有限公司 | Procedure for the preparation of purified cationic guar |
| CN101077892A (en) * | 2007-06-28 | 2007-11-28 | 上海东升新材料有限公司 | Cation guar gum and preparing process thereof |
| CN101768225A (en) * | 2010-02-10 | 2010-07-07 | 刘东辉 | Cation guar gum with transparent gum liquid and preparation method thereof |
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Application publication date: 20130123 |