废纸纤维近临界水解获取5-羟甲基糠醛的研究

STUDY ON PREPARATION OF 5-HYDROXYMETHYL FURFURAL BY HYDROLYSIS OF WASTE PAPER FIBER IN NEAR-CRITICAL WATER

以废纸纤维为原料,研究温度、反应时间、原料浓度、反应压力对废纸纤维近临界水解获取5-羟甲基糠醛(5-HMF)的影响,同时考察前驱物六碳糖和水解副产物乙酰丙酸对5-HMF生成和降解的影响。最优水解条件显示:近临界温度为375℃、反应时间为200 s、原料浓度为2.4%、反应压力为19.2 MPa时,获得的5-HMF产率最大,为(10.92±0.51)%。相比原生废纸纤维,其水解残渣的结晶度由69.24%降为57.14%,残渣中仍存在一定量的纤维素,纤维素结晶结构带来的反应屏障是影响5-HMF产率的一个重要因素。

Taking waste paper fiber as the raw material, the effect of temperature, reaction time, raw materials concentration and reaction pressure on hydrolyzing waste paper fiber for 5-hydroxymethyl furfural （5-HMF） production in near-critical water was studied. The effect of the precursor six carbon sugars and levulinic acid hydrolysis byproducts on creation and decomposition of 5-HMF （hexoses） were also investigated. The maximum yield of 5-HMF can be obtained by （10.92±0.51）% under the optimal condition, such as the raw material concentration of 2.4%, reaction pressure of 19.2 MPa, near-critical temperature of 375 ℃ and reaction time of 200 s. The crystallinity of waste paper hydrolysis residue was decreased from 69.24% to 57.14% compared the original waste paper, but there were still some cellulose in the residue. The results show that the reaction constraint of cellulose crystal structure is a major factor which affects 5-HMF yield.