摘要
以偶氮染料酸性橙AO7为目标污染物,研究了单独的热活化及零价铁(ZVI)活化S2O28-(PS)降解AO7过程温度、PS浓度及ZVI投加量对AO7降解率的影响,并将2种活化方式进行了对比,最终将其联合以期获得最好的降解效果.结果表明,热活化体系对AO7的降解符合一级动力学,其反应速率随温度(室温～90℃)升高而增加,随PS浓度(1～12 mmol.L-1)升高而增加.ZVI投加量为0.2 g时,ZVI活化体系对AO7的氧化降解率最高,90 min时达到95.6%.通过加热活化体系与ZVI活化体系的比较可以看出ZVI活化是更有效的PS活化方式.热与ZVI联合活化体系对AO7的降解是两段一级动力学过程,它们的协同活化效应增加了AO7降解反应的效率,热活化体系中ZVI的加入使加热活化体系对AO7降解的表观活化能Ea由原来的130.26 kJ.mol-1降低到27.70 kJ.mol-1,使反应条件变得温和.
Effects of temperatures,PS concentrations and ZVI dosages on AO7 decomposition were investigated in sole heat and ZVI activating systems.The degradation results of two systems were compared for selecting a better activating way for AO7 degradation and finally the two activating ways were combined for getting the optimal AO7 degradation efficiency.The degradation of AO7 by Heat/PS systems followed pseudo first-order kinetics.The reaction rates increased with increasing reaction temperatures（elevated from room temperature to 90℃） and also increased when initial PS concentrations varied from 1 to 12 mmol·L-1.For ZVI activating systems（ZVI/PS systems）,the degradation rate of AO7 was the highest when ZVI dose was 0.2 g,and it reached to 95.6% within 90 min.Comparing ZVI/PS systems with Heat/PS systems,the results showed that the ZVI activation was a more effective way to activate PS than the heat activation for AO7 degradation.AO7 degradation processes by ZVI/heat/PS systems were two-stage pseudo first-order kinetic processes,and the combining of two activating ways significantly increased the reaction rates.By the addition of ZVI to the Heat/PS system,the apparent activation energy Ea of AO7 degradation reduced from the original 130.26 kJ·mol-1 to 27.70 kJ·mol-1.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2011年第10期2949-2955,共7页
Environmental Science
基金
广东省首批"节能减排"重大专项(2008A080800003)
