Cr(VI)-乙酸复合体系中硫酸盐掺杂的含钛高炉渣光催化还原Cr(VI)

采用煅烧的硫酸盐掺杂的含钛高炉渣作光催化剂，研究了Cr(VI)-乙酸(AA)复合体系中Cr(VI)的光催化还原效率，考察了初始pH值、Cr(VI)初始浓度、AA/Cr(VI)体积比、协同效率因子、光催化剂使用寿命等因素的影响. 结果表明，增大AA/Cr(VI)比到0.2%，Cr(VI)的还原效率先增大到27.55%随后逐渐降低. 酸性条件下，Cr(VI)单一体系和Cr(VI)-AA复合体系中Cr(VI)的还原率和吸附率都明显提高；相同反应时间下(110 min)，初始pH 1.5时，2种体系中Cr(VI)的还原效率分别为76.32%(单一体系)和100%(复合体系). 复合体系中协同效率因子始终大于0. 循环使用5次后催化剂对Cr(VI)的光催化还原率为92.2%. Cr(VI)在Cr(VI)-AA体系中的光催化还原遵循Langmuir-Hinshelwood动力学规律.

Photocatalytic Reduction of Cr(VI) in Cr(VI)-Acetic Acid Compound System

Using calcined sulfate-modified titanium-bearing blast furnace slag as photocatalyst, the photocatalytic reduction of Cr(VI) in Cr(VI)-acetic acid (AA) compound system was studied. The effects of initial pH value, concentration of Cr(VI), AA/Cr(VI) volume ratio, synergistic effect factor and reuse on its photocatalytic reaction performance were also investigated. The results indicate that with increase of AA/Cr(VI) volume ratio up to 0.2%, the reduction efficiency of Cr(VI) significantly increases up to 27.55%, and thereafter it decreases gradually. The acidic solutions are favorable for the photocatalytic reduction of Cr(VI), and the optimum pH for the reduction of Cr(VI) is 1.5. Under the same conditions of 110 min and pH 1.5, the photocatalytic reduction efficiency of Cr(VI) is 76.32% for single Cr(VI) system and 100% for Cr(VI)-AA system. Cr(VI) is more efficiently eliminated in Cr(VI)-AA compound system than in single Cr(VI) system, and the synergistic effect factor is always greater than 0, indicating that there exists a synergistic effect in the compound system. The photocatalytic reduction of Cr(VI) in Cr(VI)-AA system follows Langmuir-Hinshelwood kinetic model.