羟基自由基抑制剂对臭氧氧化降解苯酚的影响

采用臭氧氧化法处理模拟苯酚废水,考察了废水pH以及HCO3-、CO32-、HPO42-、H2PO4-和叔丁醇等·OH抑制剂对苯酚降解效果的影响。实验结果表明:苯酚降解率随废水pH的增大而增大;当废水pH=11时,降解25 min后苯酚降解率达到99.55%,比废水pH=5时提高了50.12百分点;CO32-和H2PO4-对·OH的抑制作用分别强于HCO3-和HPO42-;当叔丁醇质量浓度由0增至50 mg/L时,苯酚降解率由99.55%降至69.19%。

Novel-structured Mo-Cu-Fe-O composite for catalytic air oxidation of dye-containing wastewater under ambient temperature and pressure

A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐programmed reduction by H2,cyclic voltammetry,and temperature‐programmed desorption by O2.The results showed that Mo6+diffused into the Cu‐Fe‐O crystal lattice and then formed a new crystalline phase of CuMoO4.The Mo‐Cu‐Fe‐O catalyst had redox properties,and its surface contained active sites for oxygen adsorption.In addition,the catalytic activity of the Mo‐Cu‐Fe‐O composite was evaluated by the degradation of Cationic Red GTL,Crystal Violet,and Acid Red in catalytic wet air oxidation(CWAO)at ambient temperature and pressure.The Mo‐Cu‐Fe‐O catalyst showed excellent activity at basic conditions for the degradation of Cationic Red GTL.High removal efficiencies of91.5%and92.8%were achieved for Cationic Red GTL and Crystal Violet,respectively,in wastewater,and the efficiency remained high after seven cycles.However,almost no degradation of Acid Red occurred in the CWAO process.Furthermore,hydroxyl radicals were formed in the CWAO process,which induced the decomposition of the two cationic dyes in wastewater,and the toxicity of their effluents was decreased after degradation.The results indicate that the Mo‐Cu‐Fe‐O composite shows excellent catalytic activity for the treatment of wastewater contaminated with cationic dyes.

Antioxidant Activity of Ethanol Extract of Pomegranate Seed

In this study, the ethanol extract of pomegranate seed was prepared and its antioxidant activities were investigated. It was found the total phenolic content in the extract was as high as 41.791 mg GAE/g. And the extract showed high antioxidant activity measured as scavenging of DPPH radicals, hydroxyl radicals. It also exhibited strong antioxidant activity in reducing power and Rancimat test. These results demonstrated Pomegranate seeds could serve as a new source of natural antioxidant.

在烟道中脱除NOx并生成HNO3的方法

为了解决目前气体电离放电脱硝方法存在的等离子源体积庞大、能耗高、NOx脱除率低以及需要依靠传统脱硝方法的协同作用等问题,拟用小流量、高浓度的氧活性粒子[O2+,O(1D),O(3P),O3]、引发剂HO2-分别注入烟道中,与烟气中水反应生成.OH,在无吸收剂、催化剂、氧化剂及其他技术协同作用下,实现了烟道中.OH快速氧化脱除大烟气量中的微量NOx并生成HNO3溶液的整个反应过程,等离子体反应管道长度为1～8m.实验结果表明,氧活性粒子与NOx摩尔比值决定了脱除率,摩尔比选择在2～3为宜,此时NOx脱除率将达到95%左右,回收酸液中NO3-回收率达到58.1%;NOx脱除率随着实验气体温度增高而下降;O2含量增加对脱硝效果有20%左右的影响;H2O含量大于4%时脱硝率处于最高值.可见本方法不但解决气体电离放电脱硝存在的问题,同时又为大气污染治理提供一种绿色新方法.