改性电石渣干法催化净化工业废气中的NO

采用电石水解制取乙炔气体后的废渣(电石渣)脱除工业废气中的NO。结果表明：通过KOH改性之后，该电石渣NO脱除效果有显著提高；改性电石渣NO脱除率随反应温度的升高呈先增大后减小的趋势。正交实验结果显示，各因素对NO脱除率的影响顺序大小为：浸渍浓度>焙烧温度>焙烧时间。NO脱除率随着KOH浓度增加呈现先增加后下降的趋势，随着焙烧温度和焙烧时间的增加NO脱除率下降；当KOH浓度为5 mol.L⁻¹，焙烧温度为300 ℃，焙烧时间为2 h时，改性电石渣的NO脱除率可达80.66%。表征分析结果表明，改性电石渣微观结构明显发生改变，可为催化NO反应提供反应场所，生成的K₂CO₃为NO的去除提供了更多活性点位。

Dry catalytic purification of NO by modified calcium carbide slag

The waste slag from the preparation of acetylene gas by hydrolysis of CS is applied to remove NO. Results show that the NO removal effect is significantly improved after being modified by KOH. The NO removal rate of modified CS increases first and then decreases as the reaction temperature increases. Orthogonal test results show that the the influence of various factors on the NO removal rate descreases in the order of impregnation concentration, roasting temperature, and roasting time. The NO removal rate tends to increase first and then decrease with the increase of KOH concentration. The NO removal rate decreases with the increase of roasting temperature and roasting time. The NO removal rate of the modified calcium carbide slag can reach 80.66% when the KOH concentration is 5 mol·L−1, the roasting temperature is 300 ℃, and the roasting time is 2 h. Characterization analysis shows that the microstructure of the modified CS has obviously changed, which provides a reaction site for catalytic NO reaction, and the generated K2CO3 provides more active sites for NO removal.