Sulfonic acid-functionalized ionic liquid catalyzed hydrolysis of cellulose under microwave irradiation

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1 34 3 Vol 34No Journal of Zhejiang Normal UniversityNat Sci Aug * W 0 05 g 0 04 g 0 6 g 60 s O636 1 A Sulfonic acid-functionalized ionic liquid catalyzed hydrolysis of cellulose under microwave irradiation CHEN Qin 1 XIAO Wenjun 2 WU Ying 1 WU Tinghua 1 1 Institute of Physical ChemistryZhejiang Key Laboratory for Reactive Chemistry on Solid SurfacesZhejiang Normal UniversityJinhua Zhejiang China2 Key Laboratory of Fire Retardant Materials of Fujian ProvinceCollege of MaterialsXiamen UniversityXiamen Fujian China AbstractHydrolysis of cellulose in room temperature ionic liquids was carried out under microwave irradiation MWwith sulfonic acid-functionalized ionic liquids SFILsas catalysts The effect of dimethyl sulfoxide loadingwater loading and catalyst amount were investigated The result showed that hydrolysis of cellulose in 1-ally-3-methylimidazolium chloride was better than in 1-butyl-3-methylimidazolium chloride Dimethyl sulfoxide was able to sharply reduce the viscosity and increase the total reducing sugar yield The catalytic activity of the SFILs was showed to be relevant to their acidity And the optimal reaction conditions were as follows amount of SFILs 0 05 gwater 0 04 gdmso 0 6 gmicrowave power 640 W and irradiation time 60 s MW seemed greatly enhanced the cellulose hydrolysis Key wordscellulosehydrolysisacid-functionalized ionic liquidsmicrowave * C thwu@ zjnu cn

2 Swatloski BmimCl 10% 4 5BmimCl 100 Cole 6 - SO 3 H Brosted /s BmimCl 82 1 g 1 mol 97 2 g 1 05 mol 500 ml 200 ml 48 h / 1 H NMR400 MHz CDCl 3 δ0 95 ~ 1 003H t1 34 ~ 1 462H m1 87 ~ 1 972H m4 153H s7 511H s7 611H s10 831H s AmimCl 1 H NMR400 MHz CDCl 3 δ4 06 3H s4 942H d5 41H d5 91 ~ 5 971H m7 421H s7 651H s10 441H s HmimCl 20 g 36% 30 g 2 h 1 H NMR400 MHz CDCl 3 δ4 121H s7 171H s7 401H s9 751H s15 801H s SFIL1 20 g ml 20 g

3 h 9 g 80 6 h 3 SFIL1 1 H NMR400 MHz D 2 Oδ1 878m 2H ~ 2 493t 2H3 470s 3H3 928t 2H7 027s 1H7 091s 1H8 031s 1H SFIL SFIL3 SFIL2 1 H NMR 400 MHz D 2 Oδ1 953m 2H2 011s 3H2 582t 2H3 5s 3H3 952t 2H6 975d 1H 7 035s 1H s 1H d 1H s 1H SFIL3 1 H NMR400 MHz D 2 Oδ 1 917m 2H2 397 ~ 2 527t 2H3 510s 3H3 968t 2H7 074s 1H7 138s 1H8 353 s 1H mol /L TU g 0 1 g 100 DMSO 640 W NaOH DNS 182 g 6 3 g DNS 262 ml 2 mol /L NaOH 500 ml 5 g 5 g ml 1 ml 1 ml DNS min 10 ml 540 nm M TRS Y = 0 9 M TRS /M Ce M Ce M TRS = φ V ρ φ V ρ AmimCl BmimCl 63 1% 32 0% 2 AmimCl BmimCl AmimCl Seddon 13 20% 50% AmimCl

4 % 0 6 g 59 2% 0 6 g HmimCl 49 5% SFIL1 Hammett H 0 = pk aq I+ log I s / IH + s I pk aq I AmimCl 2 g 0 1 g SFIL 0 05 g 0 04 g DMSO 0 6 g 640 W 60 s pk a I IH pk aq I= nm 380 nm I/ IH + H H 0 HmimCl SFIL1 H 0 = 1 28 H 0 = 1 24 SFIL1 > SFIL3 > SFIL2 > HmimCl SFIL1

5 Hammett A max x /% x /% H HmimCl SFIL SFIL SFIL H 2 SO pk aq I= mol /L mol /L 380 nm g 70 s 59% 0 05 g 60 s 69% 0 08 g 50 s AmimCl 2 g 0 1 g0 04 g DMSO 0 6 g 640 W SFIL g 0 05 g s 49 7% g 4 50 s AmimCl 2 g 0 1 g DMSO 0 6 g SFIL g 640 W 70 s 59 9% 0 04 g 20 s 35 4% 40 s 65 5%

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