滩涂石油污染高级氧化修复技术

在模拟原沉积物弱碱性及含水率的条件下,分别研究了2种高级氧化反应体系:H2O2辅助加入催化剂FeSO4或Fe2(SO4)3及Na2S2O8辅助加入催化剂FeSO4或CaO及热催化对污染滩涂沉积物中石油烃的去除效果及其影响因素。同时,还模拟研究了长江口潮汐作用对滩涂石油污染修复效果的影响。研究表明:H2O2与样品的质量投加比为0.05,FeSO4和Fe2(SO4)3与H2O2摩尔投加比均为0.1时,石油烃去除率分别达到48.9%和57.4%;Na2S2O8本身氧化能力较强,单一Na2S2O8与样品的质量比大于0.01时,石油烃去除率达到46%以上;而在Na2S2O8最佳投加比条件下,FeSO4、CaO与Na2S2O8摩尔比为0.05和0.9时,去除率分别达到60.4%和51.3%以上,同时最佳催化温度为50 ℃。潮汐作用对芬顿试剂氧化修复滩涂石油污染具有促进作用,而高浓度污染滩涂区域建议采用阻隔修复。

Advanced oxidation technology for remediation of petroleum-contaminated tidal flat

Through simulating the pH and moisture content of original sediment, two different types of advanced oxidation reaction systems:H2O2 catalyzed by FeSO4 or Fe2(SO4)3 and Na2S2O8 catalyzed by FeSO4 or CaO and heat, were chosen to investigate the removal effect of petroleum hydrocarbon in the tidal flat sediment. At the same time, bench scale experiments were conducted to study how the tidal action which was simulated at the laboratory influence the remediation efficiency of petroleum-contaminated tidal flat at the Yangtze estuary. The results indicated that, when H2O2/sediment ratio was 0.05 and FeSO4 or Fe2(SO4)3/H2O2 (mol/mol) ratio was 0.1, the removal rates of petroleum were 48.9% and 57.4%, respectively. Under condition of no catalyst, when Na2S2O8/sediment weight ratio surpassed 1%, more than 46% of petroleum was removed. At the optimal Na2S2O8/sediment weight ratio, the removal rates of petroleum were 60.4% and 51.3%, respectively as Fe2+/Na2S2O8(mol/mol)=0.05 or CaO/Na2S2O8 (mol/mol)=0.9 and the optimal activated temperature was 50 ℃. Tidal action has a promoting effect on the remediation of petroleum-contaminated tidal flat by Fenton, while for the polluted area of high concentration, in-situ blocking remediation is more suitable.