微晶纤维素基复合材料的制备及其对亚甲基蓝的催化降解性能

Preparation of modified microcrystalline cellulose based composite and its catalytic degradation performance on methylene blue

以微晶纤维素(MCC)为原料,通过在其表面负载纳米氧化铜颗粒(CuO NPs),添加3-氯丙基三甲氧基硅烷(CPTES)与二乙醇胺(DEA)进行接枝反应制备CuO NPs@MCC–Si–N(OH)2复合材料。探讨了DEA添加量对CuO NPs@MCC–Si–N(OH)2性能的影响,表征并分析了改性微晶纤维素红外光谱、晶体结构、表面形貌和热稳定性。结果表明,CuO NPs可成功负载在MCC表面,硅烷偶联剂可提高复合材料的分散性与接枝胺基的能力,进而增强其催化活性,使硼氢化钠(NaBH4)与亚甲基蓝(MB)氧化还原反应效率增加,快速降解MB染色剂。通过优化发现DEA用量为20wt%时制得的CuO NPs@MCC–Si–N(OH)2催化效果最佳,CuO NPs@MCC–Si–N(OH)2和NaBH4的用量分别为30 mg和10 mg,处理30 mL 3 mmol/L MB溶液5 min后,MB去除率可达99.71%,五次循环性测试后,去除率为93.24%。

Microcrystalline cellulose(MCC)was used as raw materials and loaded with CuO nanoparticles(CuO NPs).Then,3-chloropropyltrimethoxysilane(CPTES)and diethanolamine(DEA)were added for grafting reaction to prepare CuO NPs@MCC–Si–N(OH)2.CuO NPs@MCC–Si–N(OH)2 was characterized with FTIR,XRD,thermal gravimetric analysis and morphology analysis.The results show that CuO NPs can be successfully loaded on the surface of MCC,and silane coupling agent can improve the dispersion of the composite and the ability to graft amine groups,thus enhancing its catalytic activity,and increasing the redox reaction efficiency of sodium borohydride(NaBH4)and methylene blue(MB).Hence,MB stain is degraded rapidly.It’s also found that CuO NPs@MCC–Si–N(OH)2 with 20wt%DEA shows the best catalytic effect,and the highest removal efficiency is 99.71%after treating 30 mL MB solution(3 mmol/L)with 30 mg CuO NPs@MCC–Si–N(OH)2 and 10 mg NaBH4 within 5 min,and the removal rate is 93.24%after five cycles.