咪唑类高铼酸盐催化微晶纤维素降解反应研究

Degradation of cellulose catalyzed by imidazolium perrhenate

以咪唑类高铼酸盐为催化剂,以离子液体1-烯丙基-3-甲基咪唑氯盐([Amim]Cl)为溶剂降解微晶纤维素(MCC)。分别考察反应温度、反应时间、反应物浓度、催化剂用量和结构对纤维素降解反应的影响。结果表明,以5%1-(3-磺酸)丙基-3-甲基咪唑高铼酸盐([mim-(CH_2)_3SO_3H]ReO_4)为催化剂,在微波辅助加热条件下,0.1 g纤维素在2.0 g离子液体[Amim]Cl中于160℃降解30 min,还原糖收率(TRS)和葡萄糖收率最高可达89.6%和46.7%。研究还对咪唑类高铼酸催化纤维素降解反应的催化机理进行讨论,认为催化剂芳环阳离子。

Imidazolium perrhenate was applied as the catalyst to promote the degradation of microcrystalline cellulose（MCC） with the solvent of ionic liquid 1-allyl-3-methyl imidazolium chloride（[Amim]Cl）. The effects of reaction temperature,reaction time,reactant concentration,the amount and structure of catalyst on the degradation of cellulose were studied in details. When using 5% of [mim-（CH2）3 SO3 H]ReO4,70 μL of water,0.1 g cellulose and 2.0 g [Amim]Cl under microwave irradiation for 30 min at 160 ℃,89.6% of total reducing sugar（TRS） and 46.7% of glucose yield can be obtained. The degradation mechanism of cellulose catalyzed by imidazolium perrhenate was also studied.The hydrogen bonding between hydroxyl groups of cellulose and ReO4 anion and aromatic ring cation of catalyst is assumed to be the key step for depolymerization of cellulose.