含铜尖晶石催化剂在苯酚催化湿式氧化降解中铜溶出的研究

利用溶胶-凝胶法制备了Cu0.10Zn0.90Al1.90Fe0.10O4尖晶石结构催化剂,并用于苯酚的催化湿式氧化降解反应,考察了催化剂在H2-TPR实验中的氧化-还原性能,苯酚作为还原剂、反应温度和苯酚,催化剂质量比对铜离子溶出量的影响.结果表明,在较低反应温度或较高苯酚/催化剂质量比的情况下,被还原的催化剂活性组分不易被再氧化是导致铜离子大量溶出的主要因素.当反应温度较高和苯酚/催化剂质量比较低时,铜离子溶出量显著减少.在190℃、苯酚浓度为4.29 g·L-1、催化剂用量为25 g·L-1的条件下反应2 h,铜离子溶出量仅为0.96 mg·L-1.

Copper Leaching in Catalytic Wet Oxidation of Phenol with Cu-containing Spinel

Abstract: The Cu0.10Zn0.90Al1.90Fe0.10O4 spinel type catalyst prepared by sol-gel method was tested for catalytic wet air oxidation of phenol. The performances of Cu0.10Zn0.90Al1.90Fe0.10O4 catalyst in TPR experiment, the influence of phenol as reducer, reaction temperature and phenol-to-catalyst mass ratio on copper leaching were checked respectively. According to the experimental results it is suggested that the reduced active species can not be easily re-oxidized under low reaction temperature and high phenol-to-catalyst mass ratio are the main reasons for copper leaching. Under high enough reaction temperature and low phenol-to-catalyst mass ratio, the copper leaching reduces remarkably. At 1900C in the presence of 100mL aqueous solution of 4.29 g?L-1 of phenol and 2.5g catalyst, the copper leaching was only 0.96mg?L-1 after 2h of reaction.