催化湿式氧化复合催化剂对偶氮染料废水的降解

Dye wastewater treatment using composite catalysts in catalytic wet peroxide oxidation

以C包覆海绵铁(SI-C)为载体,La、Mn、Ni的硝酸盐为前驱物,采用混合浸渍焙烧法制备了SI-C表层负载金属催化剂(Mn-Ni/C、Mn-La/C、Ni-La/C、Mn-Ni-La/C),以H2O2为氧化剂,研究常温常压下H2O2与催化剂协同作用处理偶氮染料模拟废水的效果,并对其制备条件和性能进行探讨.结果表明,负载型Mn-Ni-La/C在催化湿式过氧化氢氧化(CWPO)中降解效果最好,且0.02 mol·L-1的La、Mn、Ni硝酸盐金属浸渍液以体积比1:1:1均匀混合,300℃焙烧2 h条件下制得的催化剂效果最佳;通过海绵铁固定床外加高频交变磁场,实现一种新型热传递方式下的感应热非均相反应处理有机废水.以海绵铁为感应磁核,形成固-液界面高温微反应区,促进非均相催化反应的进行.实验结果显示直接蓝D-3GL的去除率达98.39%,对直接紫D-BL的去除率达97.56%,对直接大红D-GLN的去除率达92.18%.

Three transition metals La, Mn, Ni were had been used as active components to prepare supported catalysts Mn-Ni/C, Mn-La/C, Ni-La/C, Mn-Ni-La/C in which SI/C were used as carrier. The degradation efficiency of azo dyes was investigated at the room temperature and atmospheric pressure by adding H2O2. Results showed that the degradation effiaency of the loaded Mn-Ni-La/C was the highest catalytic wet peroxide oxidation （CWPO）. Optimum preparation conditions of the catalysts were volume ratio of 1 to 1, 0.02mol.L- 1 La, Mn, Ni nitrate for metal pickling liquid, calcination at 300 ℃for 2 h, and dosing quantity of 15 mL. L-1 H2O2. A novel thermal transfer pathway in the aqueous heterogeneous reaction was realized via the sponge iron fixed bed with high frequency alternating magnetic field. With sponge iron as the induction magnetic cores, the induction heating fixed bed formed a high temperature solid-liquid interface reaction zone, deriving from the ferromagnetic heating in the micro-reaction zone, which promoted the heterogeneous catalytic reaction. The induction heating fixed bed dynamic experiment indicated the removal rate on direct blending blue D-3GL was 98. 39%, direct blending purple D-BL was 97. 56%, direct blending red D-GLN was 92.18%.