活性炭催化过二硫酸盐降解水中AO7  

Activated Carbon Catalyzed Persulfate Oxidation of Azo Dye Acid Orange 7 in Aqueous Solution

作　　者：杨鑫[1,2] 杨世迎[1,2] 王雷雷[2] 邵雪停[2] 牛瑞[2] 单良[2] 张文义[2] 

机构地区：[1]海洋环境与生态教育部重点实验室,青岛266100 [2]中国海洋大学环境科学与工程学院,青岛266100

出　　处：《环境科学》2011年第7期1960-1966,共7页Environmental Science

摘　　要：过二硫酸盐(persulfate,PS)活化技术是基于硫酸根自由基(SO 4-.)的一种新型高级氧化技术.用颗粒状活性炭(GAC)常温常压下直接非均相催化PS来降解水中难生化偶氮染料AO7(acid orange 7).结果表明,GAC/PS体系对AO7不但能够快速脱色,而且有较高的矿化率.n(PS)∶n(AO7)为100∶1,GAC为1.0 g/L的条件下,5 h内AO7脱色率达80%,萘环去除率50%左右,TOC去除率为48%.GAC作为催化剂,在反应过程中可以重复使用多次.随着使用次数的增加,GAC部分失活,但随着氧化剂浓度的增加,GAC失活程度减少.当n(PS)∶n(AO7)为500∶1,GAC投加量为1 g/L的条件下,GAC在4次使用过程中5 h内对AO7溶液的脱色率几乎没有太大变化,均高于90%.重复使用后GAC的吸附能力随着使用次数的增加而减少,其表面含氧官能团以及扫描电镜(SEM)和能谱分析图(EDS)变化不大.因此,GAC重复使用过程中失活的原因主要是由于有机物在GAC表面的吸附引起的.Persulfate oxidation is a recently emerging advanced oxidation process for the pollution control.Persulfate（PS） degradation of azo dye acid orange 7（AO7） in an aqueous solution was studied in the presence of suspended granular activated carbon（GAC） at ambient temperature（e.g.,25℃）.It was observed that in the GAC/PS combined system AO7 was not only a good decolorization as well as a good mineralization.The AO7 decolorization ratio,the removal efficiency of the naphthalene ring and the removal of TOC were 80%,50% and 48%,respectively,at PS/AO7 molar ratio of 100∶1,GAC dosage of 1.0 g/L in 5 h reaction time.As a catalyst,GAC can be reused for several times.For each reuse cycle,AO7 removal efficiencies gradually decreased,however,with the oxidant concentration increased,the extent of the deactivation of GAC decreased.The removal efficiencies of AO7 for each reuse cycle hardly changed,and were all above 90% at PS/AO7 molar ratio of 500∶1,GAC dosage of 1.0 g/L in 5 h reaction time.The adsorption capacity of reused GAC decreased as the reuse time increased.The results of surface oxygen function groups,scanning electron microscopy（SEM） and energy disperse spectroscopy（EDS） analysis of reused GAC changed slightly.Therefore,the reason leading to deactivation of GAC could be that adsorption took up the active sites,thus reducing PS＇s opportunities to contact with the surface of GAC.

关 键 词：过二硫酸盐 活性炭 非均相催化 重复使用 有机污染物降解 偶氮染料 

分 类 号：X703.1[环境科学与工程—环境工程]