Ni2O3-MnO2-CeO2/γ-Al2O3非均相催化剂处理甲基橙废水研究
2020-08-25彭文博吴正雷王肖虎
彭文博 吴正雷 王肖虎



摘 要: 以γ-Al2O3为载体,采用浸渍法自制负载型Ni2O3-MnO2-CeO2/γ-Al2O3非均相催化剂,利用EDS、SEM和XPS等表征手段对催化剂的表面形貌、组成元素等进行表征。结果表明负载的活性组分颗粒大小趋于均匀,分散性和比表面积明显提高。将制备的催化剂用于处理甲基橙模拟的印染废水,考察了氧化剂次氯酸钠投加量、反应温度、反应时间、催化剂投加量和溶液pH等因素对降解甲基橙的影响,得出最佳的反应工艺为:25 ℃时,次氯酸钠投加量0.1 mL、催化剂投加量5 g、pH值为6、反应5 min,此条件下体积100 mL,浓度为20 mg/L甲基橙的降解率可达98.5%。
关 键 词:非均相催化剂;催化氧化;次氯酸钠;甲基橙
中图分类号:X703.1 文献标识码: A 文章编号: 1671-0460(2020)05-0867-05
Abstract: Supported Ni2O3-MnO2-CeO2/ -Al2O3 heterogeneous catalysts were prepared by immersion method with-Al2O3 as carrier. The catalysts were characterized by EDS,SEM and XPS techniques for surface morphology and component elements in the catalysts. The results of EDS,SEM and XPS indicated that the catalysts had better dispersivity of active components and specific surface area. Then, Ni2O3-MnO2-CeO2/-Al2O3 heterogeneous catalysts were applied to treat the methyl orange simulation wastewater. The effect of some factors such as NaClO dosage, catalyst dosage, pH, reaction temperature and time on the degradation of methyl orange was investigated. The results showed that by adding 5 g catalyst and 0.1 mL NaClO, under the conditions of pH = 6, temperature of 25 ℃ and treatment time of 5 min, the degradation ratio of 20 mg/L methyl orange (100 mL) reached 98.5%.
Key words: Heterogeneous catalyst; Catalytic oxidation; Sodium hypochlorite; Methyl orange
印染行业废水排放量大,成分复杂,色度高,处理难,是较难处理的一类废水,且大部分废水含有偶氮染料,具有致癌性,不仅会影响人体健康,还会在水中积累并抑制水生生物的生长,因此,含偶氮染料废水的有效治理是目前工业废水处理的重要组成部分[1,2]。目前,处理印染废水的方法主要有生物法[3-5]、物理法[6,7]和化学法[8,9]。其中化学法是利用各种氧化剂将染料分子发色基团的不饱和键断开,形成分子量较小的有机物,从而使染料失去发色能力,同时可有效降低废水COD。近年来化学法成为印染废水脱色和降COD较为有效的手段之一[10],但单纯使用氧化剂(如臭氧、次氯酸钠、二氧化氯和H2O2等)的氧化效率低,研究发现通过投加催化剂可以有效提高氧化剂的利用率和处理效果[11]。Ruzimuradov等[12]制备了N-La共掺杂SrTiO3–TiO2复合光催化剂降解罗丹明B,结果表明,可见光照射2 h后,对罗丹明B的降解率达到64%。……
