CN102504274B - Method for homogeneously derivatizing plant fiber raw material by taking ionic liquid as medium - Google Patents
Method for homogeneously derivatizing plant fiber raw material by taking ionic liquid as medium Download PDFInfo
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- CN102504274B CN102504274B CN201110294393.8A CN201110294393A CN102504274B CN 102504274 B CN102504274 B CN 102504274B CN 201110294393 A CN201110294393 A CN 201110294393A CN 102504274 B CN102504274 B CN 102504274B
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- ionic liquid
- plant fiber
- fiber material
- derivatize
- imidazoles
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Abstract
The invention relates to a method for homogeneously derivatizing a plant fiber raw material by taking an ionic liquid as a medium. The method comprises the following steps of: (1) adding the plant fiber raw material into the ionic liquid; (2) dissolving at the temperature of 80-140 DEG C for 0.5-48 hours to obtain a reaction mixed solution; (3) leaching and separating the reaction mixed solution with a stainless steel filer screen; (4) adding a derivatization reagent into a filtrate, and undergoing an acylation reaction at the temperature of 70-130 DEG C for 1-10 hours; (5) after reacting, adding a precipitant into the mixed solution to separate a product out, filtering and drying to obtain a plant fiber derivatized product; and (6) distilling the filtrate under reducing pressure and recovering to obtain the ionic liquid. The method disclosed by the invention is simple and practicable, and the obtained plant fiber has a high derivatization degree.
Description
Technical field
The present invention relates to a kind of vegetable fibre treatment process, particularly, the present invention relates to a kind of method of the plant fiber material homogeneous phase derivatize taking ionic liquid as medium.
Background technology
The worsening shortages of petrochemical industry resource and petrochemical industry are processed the serious environmental pollution bringing, and make people gradually sight be turned to the cleaner production of renewable biomass resource.Plant fiber material is abundant at occurring in nature reserves, and wide material sources serve many purposes in national life with in producing.Plant fiber material contains abundant hydroxyl, therefore can improve its character by the method for chemical modification.Timber after modification is all improving a lot aspect thermoplasticity, stability, mechanicalness, water absorbability and erosion resistance, has wide practical use in fields such as plastics, film, coating, industrial additives; The wetting ability that has simultaneously changed vegetable fibre due to chemical modification, makes its easier and hydrophobic resin compatible, has greatly increased its applicability.
Traditional Wooden modifying is all in nonhomogeneous system, uses acid catalyst, under exacting terms comparatively, realizes.The method is not only brought negative impact to environment, and technical process is tediously long, and using amount of reagent is large, and energy expenditure is high, and modification efficiency is lower.Therefore,, in the urgent need to seeking new Wooden modifying path, such as finding suitable solvent, realize the modification of timber by homogeneous process.
In recent years, ionic liquid, as a kind of novel green solvent, due to its unique structure and outstanding character, has been given play to very large advantage in plant fiber material derivatize field.
(the Thorough chemical modification of Wood-based lignocellulosic materials in ionic liquids such as Xie; Biomacromolecules; 2007; 8 (12): 3740-3748) use three kinds of ionic liquid BmimCl; AmimCl and BnmimCl; under the condition existing at pyridine; 70 DEG C; 2h has realized the homogeneous phase acidylate of Picea excelsa; find all to compare the modification of heterogeneous timber preferably, weight increases per-cent WPG and can reach more than 70%.
(the Homogeneous Esterification of Poplar Wood in an Ionic Liquid under Mild Conditions:Characterization and Properties.J.Agric.Food Chem such as Yuan; 2010; 58:11302-11310) attempted the homogeneous phase decoyl of the poplar in BmimCl ionic liquid, WPG value is the highest can reach 297.4%.But the raw material of the uses such as Xie is thermomechanical slurry, and in reaction process, has added pyridine; And Yuan etc. have carried out Benzene-ethanol extraction and ball-milling processing to poplar raw material, and in reaction process, add triethylamine.
The pre-treatment of raw material, the interpolation of catalyzer all can make process complications, cause environmental pollution, and bring difficulty to the efficient recovery of solvent.Therefore, develop a kind of simple, the eco-friendly method of technique, taking ionic liquid as medium, avoid using catalyzer etc., significant to realizing the higher value application of plant fiber material.
Summary of the invention
For the deficiencies in the prior art, one of object of the present invention is to provide a kind of method of the plant fiber material homogeneous phase derivatize taking ionic liquid as medium.
According to the method that realizes plant fiber material homogeneous phase derivatize in ionic liquid of the present invention, the method comprises the following steps:
1) in ionic liquid, add the plant fiber material that accounts for solvent quality 1～8%, at the temperature of 80～140 DEG C, vegetable fibre is dissolved, obtain mixed solution; Wherein, ionic liquid is the C of imidazoles halogen or imidazoles
1-C
6carboxylate salt, in the time that type of heating used is common oil bath, dissolution time is 6～48h, in the time that type of heating used is microwave, dissolution time is 0.5～6h;
2) by step 1) in mixed solution suction filtration separate, obtain ionic liquid solution and the residue of plant fiber material;
3) derivatization reagent is added to step 2) in the ionic liquid solution of plant fiber material, carry out homogeneous phase derivative reaction 1h～10h at 70～130 DEG C, obtain the reaction mixture that contains derivatize plant fiber material, in derivatization reagent and plant fiber material, the mol ratio of hydroxyl is 1: 1～8: 1;
4) to step 3) in reaction mixture in add water, make solid precipitation out; Wherein, the water adding and the volume ratio of ionic liquid are 2: 1～10: 1; Filtration obtains solid and filtrate; Solid is washed with water to the derivatize product that obtains plant fiber material after dry, by the dry filtrate decompression distillation ionic liquid that is recycled;
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described step 1) in plant fiber material comprise one or more in timber, agricultural crop straw, crop seeds cot and residue.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described step 1) in contain plant fiber material ionic liquid reaction solution concentration preferably 3～5%; Solvent temperature is 90～110 DEG C; While adopting common oil bath heating, dissolution time is preferably 6-15 hour; While adopting microwave heating, dissolution time preferably 2～3 hours.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described step 2) in, described suction filtration separates with stainless steel filtering net suction filtration, and the stainless steel filtering net wherein using is 200～400 orders; The aperture of stainless steel filtering net is preferably 280～340 orders.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, in step 3) in, described derivatization reagent is acid anhydrides or acyl chlorides.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, in step 3) in, described derivatize temperature is preferably 90～110 DEG C; Time is preferably 3～6h, in derivatization reagent and plant fiber material the mol ratio of hydroxyl be preferably 3: 1～8: 1.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described step 4) in the water that adds and the volume ratio of ionic liquid be 3: 1～10: 1, be preferably 4: 1～6: 1.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described can dissolving cellulos and the ionic liquid of xylogen be the C of imidazoles halogen or imidazoles
1～C
6carboxylate salt, preferably, described imidazoles halogen is imidazoles villaumite, the C of described imidazoles
1～C
6carboxylate salt is imidazoles acetate.Due to halide anion, particularly chlorion and carboxylate anion can destroy the hydrogen bond between reticulated structure and the molecule between timber macromole, therefore above two class ionic liquids all show good solubility property to plant fiber material, and Mierocrystalline cellulose and xylogen in can high efficiency extraction raw material.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described imidazoles halogen or the C of imidazoles
1～C
6the positively charged ion of carboxylate salt has following formula (I) structure:
In this structural formula, R
1and R
2for C
1～C
20alkyl, thiazolinyl or aryl, R
3, R
4, R
5independently selected from hydrogen, C
1～C
20alkyl, alkoxyl group, thiazolinyl and aryl;
Preferably, described imidazoles halogen or the C of imidazoles
1～C
6the positively charged ion of carboxylate salt has formula (II) structure:
In this structural formula, R
1and R
2for C
1～C
20alkyl, thiazolinyl or aryl;
More preferably, described imidazoles halogen or the C of imidazoles
1～C
6the positively charged ion of carboxylate salt has formula (III) structure:
In this structural formula, R
1for C
1～C
20alkyl, thiazolinyl or aryl.
According to the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium of the present invention, described ionic liquid is through all recyclable recycling of underpressure distillation.
The present inventor is by selecting suitable ion liquid solvent, and strict temperature, time, the acylating reagent addition of controlling reaction, carries out homogeneous phase derivatize to plant material.Have compared with prior art derivatize efficiency high, dissolve and the advantage such as reclaim easily, reusable edible, technique are simple, with low cost, pollution-free, gained vegetable fibre derivatize product can be used for daily use chemicals, medicine and other fields, has very strong prospects for commercial application.
Brief description of the drawings
Fig. 1 is the schematic flow sheet of the plant fiber material homogeneous phase derivatize taking ionic liquid as medium in the present invention;
Fig. 2 is acetylize pine (a) and primary pine (b)
13c CP/MAS NMR spectrogram;
Fig. 3 is the infrared spectrum of acetylize pine (a) and primary pine (b) in the present invention;
Fig. 4 is the XRD spectra of acetylize pine (a) and primary pine (b) in the present invention;
Fig. 5 is the thermogravimetric spectrogram of acetylize pine in the present invention.
Embodiment
For ease of understanding the present invention, it is as follows that the present invention enumerates embodiment.Those skilled in the art should understand, described embodiment only, for helping to understand the present invention, should not be considered as concrete restriction of the present invention.
Embodiment 1
Take the about 0.5g of pine sawdust, ionic liquid 1-allyl group-3-Methylimidazole villaumite (AmimCl) 50.0g, puts into round-bottomed flask, microwave heating to 110 DEG C, and intense mechanical stirs 2 hours.Dissolve and finish, use 300 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 1.4g, 70 DEG C of heating 2h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 156%.
Embodiment 2
Take the about 0.5g of pine sawdust, ionic liquid 1-ethyl-3-methylimidazole acetate (EmimAc) 50.0g, puts into round-bottomed flask, microwave heating to 100 DEG C, and intense mechanical stirs 2 hours.Dissolve and finish, use 400 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 0.7g, 70 DEG C of heating 3h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 95%.
Embodiment 3
Take the about 0.5g of pine sawdust, ionic liquid 1-butyl-3-methyl imidazolium villaumite (BmimCl) 50.0g, puts into round-bottomed flask, microwave heating to 100 DEG C, and intense mechanical stirs 3h.After dissolving finishes, use 280 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 2.3g, 80 DEG C of heating 24h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 149%.
Embodiment 4
Take the about 0.5g of pine sawdust, reclaim ionic liquid 1-allyl group-3-Methylimidazole villaumite (AmimCl) 50g; Put into round-bottomed flask, microwave heating to 80 DEG C, intense mechanical stirs 6h.Dissolving finishes rear use 400 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 1.1g, 100 DEG C of heating 6h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 120%.
Take poplar and consider about 0.5g to be worth doing, ionic liquid 1-allyl group-3-Methylimidazole villaumite (AmimCl) 50.0g; Put into round-bottomed flask, microwave heating to 80 DEG C, intense mechanical stirs 2h.After dissolving finishes, use 400 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 0.5g, 120 DEG C of heating 2h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 80%.
Embodiment 6
Take the about 1.0g of bagasse, ionic liquid 1-allyl group-3-Methylimidazole villaumite (AmimCl) 50.0g; Put into round-bottomed flask, microwave heating to 100 DEG C, intense mechanical stirs 0.5h.After dissolving finishes, use 400 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 4.6g, 70 DEG C of heating 4h, after dissolving finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 125%.
Embodiment 7
Take the about 2.5g of Chinese catalpa wood chip, ionic liquid 1-ethyl-3-methylimidazole villaumite (EmimCl) 50.0g, puts into round-bottomed flask, and oil bath is heated to 120 DEG C, and intense mechanical stirs 24h.After dissolving finishes, use 200 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 4.6g, 70 DEG C of heating 2h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 120%.
Embodiment 8
Take Chinese parasol tree and consider about 4.0g to be worth doing, ionic liquid 1-phenyl-3-Methylimidazole acetate (BzmimAc) 50.0g; Put into round-bottomed flask, oil bath is heated to 140 DEG C, and intense mechanical stirs 15h.After dissolving finishes, use 280 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 28.6g, 80 DEG C of heating 15h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 118%.
Embodiment 9
Take the about 0.5g of Chinese catalpa wood chip, ionic liquid 1-phenyl-3-Methylimidazole acetate (BzmimAc) 50.0g; Put into round-bottomed flask, microwave heating to 120 DEG C, intense mechanical stirs 2h.After dissolving finishes, use 200 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 1.4g, 80 DEG C of heating 15h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 128%.
Take the about 1.0g of stalk, ionic liquid 1-ethyl-3-methylimidazole formate, puts into round-bottomed flask, and oil bath is heated to 120 DEG C, and intense mechanical stirs 4h.After dissolving finishes, use 400 order stainless steel filtering net filtering separation.
In filtrate, add diacetyl oxide 2.8g, 70 DEG C of heating 6h, after reaction finishes, add water precipitation to go out product.Filter, washing, dry obtain derivatize product, WPG value is 126%.
Applicant's statement, the present invention illustrates detailed process condition of the present invention and technical process by above-described embodiment, but the present invention is not limited to above-mentioned detailed process condition and technical process, do not mean that the present invention must rely on above-mentioned detailed process condition and technical process could be implemented.Person of ordinary skill in the field should understand, any improvement in the present invention, and the selections of the equivalence replacement to the each raw material of product of the present invention and the interpolation of ancillary component, concrete mode etc., within all dropping on protection scope of the present invention and open scope.
Claims (13)
1. the plant fiber material homogeneous phase derivatization method taking ionic liquid as medium, is characterized in that, said method comprising the steps of:
1) in ionic liquid, add the plant fiber material that accounts for solvent quality 1～8%, at the temperature of 80～140 DEG C, vegetable fibre is dissolved, obtain mixed solution; Wherein, ionic liquid is the C of imidazoles halogen or imidazoles
1-C
6carboxylate salt; In the time that type of heating used is common oil bath, dissolution time is 6～48h, and in the time that type of heating used is microwave, dissolution time is 0.5～6h;
2) the mixed solution suction filtration in step 1) is separated, obtain ionic liquid solution and the residue of plant fiber material;
3) derivatization reagent is added to step 2) in the ionic liquid solution of plant fiber material, carry out homogeneous phase derivative reaction 1～10h at 90～130 DEG C, obtain the reaction mixture that contains derivatize plant fiber material, in derivatization reagent and plant fiber material, the mol ratio of hydroxyl is 3:1～10:1; Described derivatization reagent is acid anhydrides or acyl chlorides;
4) in the reaction mixture in step 3), add water, make solid precipitation out; Wherein, the water adding and the volume ratio of ionic liquid are 2:1～10:1; Filtration obtains solid and filtrate; Solid is washed with water to the derivatize product that obtains plant fiber material after dry, filtrate decompression is distilled to dried recovered and obtain ionic liquid;
The C of described imidazoles halogen or imidazoles
1～C
6the positively charged ion of carboxylate salt comprises the structural formula of formula III:
Wherein, R
1for C
1～C
20alkyl, thiazolinyl or aryl.
2. method according to claim 1, is characterized in that, in described step 1), plant fiber material comprises one or more in timber, agricultural crop straw and crop seeds cot.
3. method according to claim 1 and 2, is characterized in that, the plant fiber material adding in described step 1) accounts for 3～5% of ionic liquid.
4. method according to claim 1 and 2, is characterized in that, solvent temperature is 90～110 DEG C.
5. method according to claim 1 and 2, is characterized in that, while adopting common oil bath heating, dissolution time is 6-15 hour.
6. method according to claim 1 and 2, is characterized in that, while adopting microwave heating, dissolution time is 2～3 hours.
7. method according to claim 1 and 2, is characterized in that, described step 2) in, described suction filtration separates with stainless steel filtering net suction filtration, and the stainless steel filtering net wherein using is 200～400 orders.
8. method according to claim 7, is characterized in that, the aperture of described stainless steel filtering net is 280～340 orders.
9. method according to claim 1 and 2, is characterized in that, in step 3), described derivatize temperature is 90～110 DEG C.
10. method according to claim 1 and 2, is characterized in that, in step 3), the described derivatize time is 3～6h.
11. methods according to claim 1 and 2, is characterized in that, in step 3), in described derivatization reagent and plant fiber material, the mol ratio of hydroxyl is 3:1～8:1.
12. methods according to claim 1 and 2, is characterized in that, the water adding in described step 4) and the volume ratio of ionic liquid are 3:1～10:1.
13. methods according to claim 12, is characterized in that, the water adding in described step 4) and the volume ratio of ionic liquid are 4:1～6:1.
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| CN101497668A (en) * | 2009-02-24 | 2009-08-05 | 华南理工大学 | Homogeneous phase modifying method for cellulose in ion liquid |
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| CN101497668A (en) * | 2009-02-24 | 2009-08-05 | 华南理工大学 | Homogeneous phase modifying method for cellulose in ion liquid |
Non-Patent Citations (6)
| Title |
|---|
| Dissolution of Wood in Ionic Liquids;ILKKA KILPELAINEN et al.;《Journal of Agricultural and Food Chemistry》;20071002;第55卷(第22期);9143页右栏第31行到37行，第9144页表1中3号和4号实验 * |
| Haibo Xie et al..Thorough Chemical Modification of Wood-Based Lignocellulosic Materials in Ionic Liquids.《Biomacromolecules》.2007,第8卷(第12期),3440-3748. |
| ILKKA KILPELAINEN et al..Dissolution of Wood in Ionic Liquids.《Journal of Agricultural and Food Chemistry》.2007,第55卷(第22期), |
| Thorough Chemical Modification of Wood-Based Lignocellulosic Materials in Ionic Liquids;Haibo Xie et al.;《Biomacromolecules》;20071103;第8卷(第12期);3741页2.3节和2.5节、3742页表1的A4实验 * |
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| 离子液体在植物纤维化学研究中的应用;刘娟娟等;《纤维素科学与技术》;20090331;第17卷(第1期);全文 * |
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