机构地区: 海南师范大学化学与化工学院
出 处: 《化学学报》 2010年第11期1037-1042,共6页
摘 要: 以Keggin型铁取代杂多阴离子PW11O39Fe(Ⅲ)(H2O)4-[PW11Fe(Ⅲ)(H2O)]代替传统光芬顿方法中的Fe3+作为光催化剂,构成一个新颖的光催化体系并用于水体生物难降解有机污染物硝基苯(NB)的降解.详细研究了在紫外光照射和H2O2存在下,PW11Fe(Ⅲ)(H2O)对NB降解的均相光催化作用.考察了NB初始浓度、溶液pH、H2O2和PW11Fe(Ⅲ)(H2O)浓度对光催化降解反应速率的影响.实验结果表明,1.0mmol·L-1PW11Fe(Ⅲ)(H2O)+5.0mmol·L-1H2O2+1.0mmol·L-1NB的中性溶液在300W汞灯照射下反应120min,NB的降解率达93%,总有机碳(TOC)去除约31%,显示了该新颖体系对NB光催化降解的高效性和优越性. A novel system using the Keggin-type PW11O39Fe(Ⅲ)(H2O)^4- [PW11Fe(Ⅲ)(H2O)] to substitute Fe^3+ in conventional photo-Fenton as a photo-catalyst was developed. This novel system was applied to degrade the aqueous biorefractory organic pollutant nitrobenzene (NB). The homogeneous photocatalytic degradation of NB by PW11Fe(Ⅲ)(H2O) was studied in detail under an artificial UV irradiation and the existence of hydrogen peroxide (H2O2), in which the effects of initial NB concentration, pH, H2O2 and PW11Fe(Ⅲ)(H2O) concentration on the photocatalytic degradation rate of NB were examined. The experimental results show that ca. 93% NB degradation ratio was obtained in less than 120 min in a pH 6.86 mixed phosphate solution containing 1.0 mmol·L^-1 NB+ 1.0 mmol·L^-1 PW11Fe(Ⅲ)(H2O)+5.0 mmol·L^-1 H2O2 under irradiation with a 300 W Hg lamp, and a total organic carbon (TOC) removal of ca. 31% was achieved, indicating an excellent efficiency and advantage in photo-catalytic degradation of NB by this novel system.
领 域: [化学工程]