非均相Fe_2O_3/γ-Al_2O_3催化降解木质素模型物愈创木酚

以等体积超声浸渍法制备负载型Fe2O3/γ-Al2O3催化剂,采用XRD、SEM、N2吸附仪对催化剂结构进行表征.研究非均相催化剂Fe2O3/γ-Al2O3催化H2O2氧化愈创木酚的降解反应,分别考察催化剂铁的负载量、催化剂加入量、H2O2加入量、初始pH对愈创木酚去除效果的影响.结果表明:该催化剂对降解愈创木酚具有较好的效果,在愈创木酚质量浓度100,mg/L、反应温度75,℃、催化剂加入量6,g/L、H2O2(质量分数30%)加入量0.030,5,mol/L、pH 6.10、反应时间80,min的条件下,愈创木酚的去除率高达92.6%.此外,该非均相体系在pH 3.0~9.0范围内都有较高的催化活性,这表明该催化剂克服了某些类Fenton催化剂在中性、碱性环境低效率的问题.催化剂重复5次使用后稳定性高,铁浸出较低,对反应影响可以忽略.

Catalytic Oxidation of Lignin Model Compound Guaiacol with Fe2O3/γ-Al2O3 Catalyst

Fe2O3/γ-Al2O3 heterogeneous catalyst was prepared with wet impregnation method and was characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and N2 adsorption. The catalyst was used for the catalytic oxi-dation of guaiacol. The effects of iron loading,catalyst dosage,initial concentration of hydrogen peroxide and initial pH on the removal efficiency of guaiacol were investigated. The results show that this new catalyst is highly effective for the degra-dation of guaiacol. With 100 mg/L of the initial concentration,an initial pH of 6.1,t=75,℃,6 g/L catalyst,0.030,5,mol/L hydrogen peroxide（30%）,the removal efficiency of guaiacol reached 92.6%within 80,min. Moreover,the catalytic activity was very good when pH ranged 3.0-9.0. This indicates that the use of Fe2O3/γ-Al2O3 can deal with the problem of low effi-ciency of Fenton-like reaction when pH is neutral and even alkaline. Fe2O3/γ-Al2O3 exhibits low iron leaching,good struc-tural stability and no loss of performance after recycling five times.