CAJ | 학술논문

以杉木屑为原料,采用原位合成法制备炭基磷钨酸催化剂,以此催化剂催化水解微晶纤维素制备纳米纤维素( NCC),考察了液料浸渍比、炭化温度及炭化时间等催化剂的制备因素对NCC得率的影响。结果表明：液料浸渍比2.5∶1(mL∶g),炭化温度350℃,炭化时间1.5 h条件下制备得到的炭基磷钨酸的催化性能较好,NCC得率可达25.28%。采用傅里叶红外光谱仪、热重分析及扫描电镜对炭基磷钨酸催化剂进行了表征,结果表明：磷钨酸较好地负载在炭材料上,炭基磷钨酸的Keggin结构特征吸收峰并未发生明显变化,磷钨酸Keggin结构开始分解的温度是370℃。用透射电子显微镜和X射线衍射仪对NCC的形貌、晶体结构进行了分析,结果表明：NCC呈棒状,直径9~70 nm,长度130~830 nm,平均长径比为11.2∶1,结晶度为76.1%,平均晶粒尺寸6.9 nm。
이삼목설위원료,채용원위합성법제비탄기린오산최화제,이차최화제최화수해미정섬유소제비납미섬유소( NCC),고찰료액료침지비、탄화온도급탄화시간등최화제적제비인소대NCC득솔적영향。결과표명：액료침지비2.5∶1(mL∶g),탄화온도350℃,탄화시간1.5 h조건하제비득도적탄기린오산적최화성능교호,NCC득솔가체25.28%。채용부리협홍외광보의、열중분석급소묘전경대탄기린오산최화제진행료표정,결과표명：린오산교호지부재재탄재료상,탄기린오산적Keggin결구특정흡수봉병미발생명현변화,린오산Keggin결구개시분해적온도시370℃。용투사전자현미경화X사선연사의대NCC적형모、정체결구진행료분석,결과표명：NCC정봉상,직경9~70 nm,장도130~830 nm,평균장경비위11.2∶1,결정도위76.1%,평균정립척촌6.9 nm。
Carbon-based phosphotungstic acid ( H3 PW12 O40 ) catalyst was prepared from sawdust of Chinese fir by in-situ synthesis. Nanocrystalline cellulose ( NCC) from cellulose by catalytic hydrolysis was studied. The effects of impregnation ratio, carbonization temperature and carbonization time on the yield of NCC were also analyzed. The results showed that under the impregnation ratio of liquid to solid 2. 5∶1, thecarbonization temperature 350 ℃ and carbonization time 1. 5 h, a comparatively high yield of NCC was observed as 25. 28%. The catalysts were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscope. The results indicated that phosphotungstic acid was loaded on the carbon under good conditions, the keggin structure characteristic absorption peak of carbon-based phosphotungstic acid remains stable, and the initial decomposition temperature of keggin structure of phosphotungstic acid is 370 ℃. The morphological and crystal structures of NCC were carried out by Transmission electron microscopy and X-ray diffraction. The results showed that the NCC observed by TEM turned out to be rod-like, with the size of 9-70 nm in width and 130-830 nm in length and the average aspect ratio of 11. 2∶1. X-ray diffraction analysis revealed that the crystallinity of the NCC was 76. 1%, with the average particle size of 6. 9 nm.