CN105728037A - Method for preparing straw-based carbon solid acid - Google Patents
Method for preparing straw-based carbon solid acid Download PDFInfo
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- CN105728037A CN105728037A CN201610120190.XA CN201610120190A CN105728037A CN 105728037 A CN105728037 A CN 105728037A CN 201610120190 A CN201610120190 A CN 201610120190A CN 105728037 A CN105728037 A CN 105728037A
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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
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0215—Sulfur-containing compounds
- B01J31/0225—Sulfur-containing compounds comprising sulfonic acid groups or the corresponding salts
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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
- B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
- B01J2231/40—Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
- B01J2231/49—Esterification or transesterification
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for preparing a straw-based carbon solid acid, and belongs to the technical field of solid acid preparation. The method disclosed by the invention comprises the following steps: performing saline soaking on wheat straws, removing inner moisture, curing and bulking the straws, and performing blasting treatment, so that gases in the pores rapidly expand, and the cohesiveness among fibers is reduced; conducting preliminary acidification on the interior through microbes, so that the combined acidic capability is enhanced; finally, mixing with saccharides to increase the acidic bonding degree, reacting with strong sulfuric acid, and performing sulfonation, so as to obtain the straw-based carbon solid acid. According to the solid acid prepared by the method disclosed by the invention, the surface acid amount is 3.7-4.3mmol/g, the thermal stability is high, the temperature can reach 190-195 DEG C, and when being used for a catalytic reaction, the solid acid is good in catalytic effect and can be repeatedly used.
Description
Technical field
The preparation method that the present invention relates to a kind of straw base carbonaceous solid acid, belongs to solid acid preparing technical field.
Background technology
Also there is acid catalyzed effect in view of solid acid; but consersion unit corrosivity is very little; and recyclable use again; production cost can be greatly reduced; it is also beneficial to the feature of protection environment; this kind of material has broad application prospects at catalytic field, thus becomes the Main way of the following acid catalyst of development.
In all types of superpower solid acids, in zeolite molecular sieve, ion exchange resin, heteropoly acid etc., especially more it is popular with carbon-based solid acid.Because carrier carbon has resistance to strong acid and the feature of resistance to highly basic, not easily react with other component of reaction system and produce interference etc..In published document, many carbonaceous materials such as wood flour, corn straw, starch, Cotton Gossypii etc. all and can be applied in different reaction systems as preparing the raw material of the superpower solid acid of carbon back, but the subject matter existed is that Surface acidity is low, it is generally 3.0～3.5mmol/g, active component loses catalytic action because of facile hydrolysis (140 DEG C are just hydrolyzed), catalytic effect is poor, and poor heat stability (softening point temperature 186 DEG C).
Summary of the invention
nullThe technical problem to be solved: low for current used solid acid Surface acidity，Activity facile hydrolysis and lose catalytic action，The problem making its catalytic effect difference，Provide to first pass through and wheat stalk is carried out saline soak，Remove internal moisture，Make it bulk again through ripening，Pass through explosion treatment subsequently，The gas in hole is made sharply to expand，Interfibrous caking property reduces，Then pass through microorganism to the preliminary acidifying in its inside，Its combined acid sexuality is made to strengthen，Again through mixing the acid conjugation of increase with glucide，Finally react with strength sulfuric acid，Sulfonating surface，Straw base carbonaceous solid acid can be prepared into，Solid acid Surface acidity prepared by the present invention reaches 3.7～4.3mmol/g，And heat stability is high，Temperature is up to 190～195 DEG C，During for catalytic reaction，Excellent catalytic effect，Can repeatedly use.
For solving above-mentioned technical problem, the present invention adopts the technical scheme as described below to be:
(1) 2～4kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 200～300g sodium sulfite to it, filter after stirring 30～50min with 150r/min, filtrate is put in baking oven, dry 1～2h at 80～90 DEG C；
(2) after above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 160～190g, put in steam explosion tank, setting pressure is 0.5～0.8MPa, temperature is 140～160 DEG C, moment explosion is carried out after keeping temperature 8～12min, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment；
(3) the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 1～3min, set nitrogen flow rate as 70～90mL/min, it is warming up to 430～480 DEG C with 5 DEG C/min, after keeping temperature carbonization 4～6h, naturally cool to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 30～50min after filter, the wheat stalk of the carbonization after filtration is put in baking oven, at 90～95 DEG C, dry 5～6h, obtains straw base carbonaceous solid acid matrix；
(4) measure biogas slurry to put in centrifuge with rotating speed 900～1100r/min centrifugation 5～10min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 3～5%, filter after standing 3～5h after stirring, collect filtrate and put in air-dry machine air-dry；
(5) weigh 800～900g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 2～4L mass fraction is 85% again, temperature is set as 150～190 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 4～8h, filter after adding 1～3L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 80～85 DEG C, dry 5～6h, can obtain straw base carbonaceous solid acid.
The application process of the present invention: utilize straw base carbonaceous solid acid prepared by the present invention to be applied in catalytic esterification, condensation and etherification reaction as catalyst, compared with making catalyst with the concentrated sulphuric acid of equivalent, catalytic efficiency improves 10～12%, and reaction terminate after the catalyst that filters out can use 6～7 times, activity remains unchanged.
The present invention is compared with additive method, and Advantageous Effects is:
(1) the solid acid Surface acidity that prepared by the present invention reaches 3.7～4.3mmol/g；
(2) heat stability is high, and temperature is up to 190～195 DEG C；
(3) time for catalytic reaction, excellent catalytic effect, can repeatedly use, preparation process is simple simultaneously, and required cost is low.
Detailed description of the invention
First 2～4kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 200～300g sodium sulfite to it, filter after stirring 30～50min with 150r/min, filtrate is put in baking oven, dry 1～2h at 80～90 DEG C；After above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 160～190g, putting in steam explosion tank, setting pressure is 0.5～0.8MPa, temperature is 140～160 DEG C, carry out moment explosion after keeping temperature 8～12min, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment；Again the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 1～3min, set nitrogen flow rate as 70～90mL/min, it is warming up to 430～480 DEG C with 5 DEG C/min, after keeping temperature carbonization 4～6h, naturally cool to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 30～50min after filter, the wheat stalk of the carbonization after filtration is put in baking oven, at 90～95 DEG C, dry 5～6h, obtains straw base carbonaceous solid acid matrix；Measure biogas slurry to put in centrifuge with rotating speed 900～1100r/min centrifugation 5～10min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 3～5%, filter after standing 3～5h after stirring, collect filtrate and put in air-dry machine air-dry；Then weigh 800～900g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 2～4L mass fraction is 85% again, temperature is set as 150～190 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 4～8h, filter after adding 1～3L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 80～85 DEG C, dry 5～6h, can obtain straw base carbonaceous solid acid.
Example 1
First 4kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 300g sodium sulfite to it, filter after stirring 50min with 150r/min, filtrate is put in baking oven, dry 2h at 90 DEG C；After above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 190g, putting in steam explosion tank, setting pressure is 0.8MPa, and temperature is 160 DEG C, carries out moment explosion, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment after keeping temperature 12min；Again the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 3min, set nitrogen flow rate as 90mL/min, it is warming up to 480 DEG C with 5 DEG C/min, after keeping temperature carbonization 6h, naturally cools to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 50min after filter, putting in baking oven by the wheat stalk of the carbonization after filtration, at 95 DEG C, dry 6h, obtains straw base carbonaceous solid acid matrix；Measure biogas slurry to put in centrifuge with rotating speed 1100r/min centrifugation 10min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 5%, filter after standing 5h after stirring, collect filtrate and put in air-dry machine air-dry；Then weigh 900g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 4L mass fraction is 85% again, temperature is set as 190 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 8h, filter after adding 3L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 85 DEG C, dry 6h, can obtain straw base carbonaceous solid acid.Utilizing straw base carbonaceous solid acid prepared by the present invention to be applied in catalytic esterification as catalyst, compared with making catalyst with the concentrated sulphuric acid acid of equivalent, catalytic efficiency improves 12%, and reaction terminate after the catalyst that filters out can use 7 times, activity remains unchanged.
Example 2
First 2kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 200g sodium sulfite to it, filter after stirring 30min with 150r/min, filtrate is put in baking oven, dry 1h at 80 DEG C；After above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 160g, putting in steam explosion tank, setting pressure is 0.5MPa, and temperature is 140 DEG C, carries out moment explosion, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment after keeping temperature 8min；Again the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 1min, set nitrogen flow rate as 70mL/min, it is warming up to 430 DEG C with 5 DEG C/min, after keeping temperature carbonization 4h, naturally cools to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 30min after filter, putting in baking oven by the wheat stalk of the carbonization after filtration, at 90 DEG C, dry 5h, obtains straw base carbonaceous solid acid matrix；Measure biogas slurry to put in centrifuge with rotating speed 900r/min centrifugation 5min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 3%, filter after standing 3h after stirring, collect filtrate and put in air-dry machine air-dry；Then weigh 800g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 2L mass fraction is 85% again, temperature is set as 150 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 4h, filter after adding 1L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 80 DEG C, dry 5h, can obtain straw base carbonaceous solid acid.Utilizing straw base carbonaceous solid acid prepared by the present invention to be applied in catalyzing and condensing reaction as catalyst, compared with making catalyst with the concentrated sulphuric acid acid of equivalent, catalytic efficiency improves 10%, and reaction terminate after the catalyst that filters out can use 6 times, activity remains unchanged.
Example 3
First 3kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 250g sodium sulfite to it, filter after stirring 40min with 150r/min, filtrate is put in baking oven, dry 1h at 85 DEG C；After above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 170g, putting in steam explosion tank, setting pressure is 0.7MPa, and temperature is 150 DEG C, carries out moment explosion, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment after keeping temperature 10min；Again the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 2min, set nitrogen flow rate as 80mL/min, it is warming up to 450 DEG C with 5 DEG C/min, after keeping temperature carbonization 5h, naturally cools to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 40min after filter, putting in baking oven by the wheat stalk of the carbonization after filtration, at 92 DEG C, dry 6h, obtains straw base carbonaceous solid acid matrix；Measure biogas slurry to put in centrifuge with rotating speed 1000r/min centrifugation 7min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 4%, filter after standing 4h after stirring, collect filtrate and put in air-dry machine air-dry；Then weigh 850g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 3L mass fraction is 85% again, temperature is set as 170 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 5h, filter after adding 2L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 82 DEG C, dry 5h, can obtain straw base carbonaceous solid acid.Utilizing straw base carbonaceous solid acid prepared by the present invention to be applied in catalyst etherifying reaction as catalyst, compared with making catalyst with the concentrated sulphuric acid acid of equivalent, catalytic efficiency improves 11%, and reaction terminate after the catalyst that filters out can use 6 times, activity remains unchanged.
Claims (1)
1. the preparation method of a straw base carbonaceous solid acid, it is characterised in that concrete preparation process is:
(1) 2～4kg wheat stalk is weighed, use clear water by clean for its surface washing, again the straw after flushing is put in pulverizer and pulverize, cross 40 mesh sieves, the granule of gained after sieving is soaked in the hydrochloric acid solution that mass fraction is 5%, and adds 200～300g sodium sulfite to it, filter after stirring 30～50min with 150r/min, filtrate is put in baking oven, dry 1～2h at 80～90 DEG C；
(2) after above-mentioned dried filtrate being mixed homogeneously with the sodium carbonate of 160～190g, put in steam explosion tank, setting pressure is 0.5～0.8MPa, temperature is 140～160 DEG C, moment explosion is carried out after keeping temperature 8～12min, then naturally cool to room temperature, obtain the wheat stalk of explosion treatment；
(3) the above-mentioned wheat stalk through explosion treatment is put in tubular type retort, after using nitrogen to purge retort 1～3min, set nitrogen flow rate as 70～90mL/min, it is warming up to 430～480 DEG C with 5 DEG C/min, after keeping temperature carbonization 4～6h, naturally cool to room temperature, will be cooled to the wheat stalk of room temperature put into the alcoholic solution that mass fraction is 18% of 20 DEG C soaks 30～50min after filter, the wheat stalk of the carbonization after filtration is put in baking oven, at 90～95 DEG C, dry 5～6h, obtains straw base carbonaceous solid acid matrix；
(4) measure biogas slurry to put in centrifuge with rotating speed 900～1100r/min centrifugation 5～10min, collect supernatant, the straw base carbonaceous solid acid matrix of above-mentioned gained is soaked in supernatant, add the glucose of straw base carbonaceous solid acid substrate quality 3～5%, filter after standing 3～5h after stirring, collect filtrate and put in air-dry machine air-dry；
(5) weigh 800～900g above-mentioned air-dry after filtrate put into reactor, it is added thereto to the concentrated sulphuric acid that 2～4L mass fraction is 85% again, temperature is set as 150～190 DEG C, with discharging after rotating speed 150r/min stirring sulfonation 4～8h, filter after adding 1～3L distilled water mix homogeneously in discharging thing, collect filtrate, the distilled water flushing filtrate using temperature to be 90 DEG C, until flushing liquor pH to 7.0, then the filtrate after flushing is put in vacuum drier, at 80～85 DEG C, dry 5～6h, can obtain straw base carbonaceous solid acid.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610120190.XA CN105728037A (en) | 2016-03-03 | 2016-03-03 | Method for preparing straw-based carbon solid acid |
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| CN201610120190.XA CN105728037A (en) | 2016-03-03 | 2016-03-03 | Method for preparing straw-based carbon solid acid |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107254791A (en) * | 2017-06-07 | 2017-10-17 | 常州中翔科技有限公司 | A kind of method of waste crop straws recycling |
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2016
- 2016-03-03 CN CN201610120190.XA patent/CN105728037A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107254791A (en) * | 2017-06-07 | 2017-10-17 | 常州中翔科技有限公司 | A kind of method of waste crop straws recycling |
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