CuAPO-5分子筛催化氧化水溶液中苯酚的性能

CuAPO-5 molecular sieve as catalyst for oxidation of phenol in aqueous solutions

以水热晶化法合成了铜磷铝分子筛CuAPO-5,并用XRD、SEM,FT-IR,UV-Vis等对样品进行了表征,结果表明Cu2+进入到了AlPO4-5分子筛骨架中。研究了以CuAPO-5为催化剂,H2O2为氧化剂对水溶液中苯酚的催化氧化性能。在苯酚初始浓度200 mg/L、H2O2添加量1 200 mg/L、pH值5.0、处理温度80℃时,处理240 min时苯酚去除率达到100%,TOC去除率达81.76%,析出到溶液中Cu2+浓度仅为0.527 mg/L。温度从40℃上升到80℃时,苯酚的去除率及TOC去除率明显增大,表明温度对催化剂的活性影响显著,相比于均相催化剂骨架Cu催化过氧化氢分解需要更多的能量。重复性实验表明,催化剂性能稳定。

Cu-substituted aluminophosphate molecular sieve （CuAPO-5） was synthesized by hydrothermal crystallization and characterized by XRD, SEM, FT-IR, UV-Vis. The results showed that Cu^2＋ had incorporated into the AlPO4-5 framework. Catalyst based on CuAPO-5 and H2O2 as oxidant for catalytic oxidation of phenol in aqueous solutions was investigated. Under the conditions of phenol initial concentration 200 mg/L, H2O2 concentration 1 200 mg/L and pH 5.0, the phenol removal rate reaches 100% and TOC removal rate reaches 81.76% at 80 ℃ after treatment for 240 min. The leaching-off Cu^2＋ from catalyst into aqueous solutions is only 0. 527 mg/L by ICP analysis. Both the phenol removal and TOC removal increase appearently at the temperature from 40 ℃ to 80 ℃, which indicates that the activity of the catalyst is significantly affected by temperature and Cu species in the molecular sieve framework seem to require more energy than that of homogeneous Cu^2＋ to generate · OH radicals from H2O2. The repeating experiments show that CuAPO-5 catalyst is stable in catalytic oxidation phenol in aqueous solutions.