咪唑类高铼酸盐催化微晶纤维素降解反应研究

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、ReO-4中Re=O与纤维素分子中羟基的相互作用是促进纤维素降解的关键

Degradation of cellulose catalyzed by imidazolium perrhenate

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% ofmim-(CH₂)₃SO₃H]ReO₄, 70μL of water, 0.1g cellulose and 2.0gAmim]Cl under microwave irradiation for 30min 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.