RuO_2/La_2O_3/TiO_2悬浮体系中直接耐晒黑G的光催化降解

Photocatalytic degradation of direct fast black G by RuO_2/La_2O_3/TiO_2 suspension

钛酸丁酯为前驱体,采用溶胶凝胶浸渍法制备RuO2 /La2O3 /TiO2 复合光催化剂,以紫外灯为光源,研究了催化剂组成、煅烧温度、溶液pH值等因素对直接耐晒黑G(DFBG)光催化降解的影响。结果表明:掺杂量w(La2O3 )1 .39%、w(RuO2 )0 .12%、煅烧温度500℃(2h)、溶液pH值7. 3时,光催化活性最佳。当通气量为200mL/min,催化剂投加量为150mg时, 50mg/L的DFBG溶液经60min降解,其降解率近100%。DFBG的光催化降解服从Langmuir Hinshelwood动力学模型,测得相应的动力学参数k=7 .42×10-3 mmol/L·min,K=19 54L/mmol。

RuO_2/La_2O_3/TiO_2 coupled photocatalyst was prepared by the sol-gel-immersion process with Ti(OC_4H_9)_4 as a precursor.The photocatalytic degradation of direct fast black G (DFBG) in RuO_2/La_2O_3/TiO_2 powder suspension under UV irradiation was investigated. As results, the addition of RuO_2 and La_2O_3 to TiO_2 greatly enhanced its photocatalytic activity. When w(RuO_2)=0.12%,w(La_2O_3)=1.39%, calcined at 500 ℃ for 2 h, the DFBG dye was almost completely degraded in 60 min in the solution of the pH 7.3 with the air flow rate 200 mL/min and the addition of coupled photocatalyst 150 mg. The results demonstrated that the photocatalytic degradation of DFBG follows the Langmuir-Hinshelwood kinetic model, and the kinetic constants k and K values were determined to be 7.42×10 -3 mmol/L·min and 19.54 L/mmol,respectively.