多孔陶瓷负载钯催化剂及污水处理研究

Study on Loading of Palladium Catalyst on Porous Ceramics and Sewage Treatment

摘要:

本研究以廉价的高岭土、滑石粉、氧化铝为主要原料，水泥为固化剂，疏水型活性碳粉为泡沫稳定剂，采用直接起泡法制备了高开气孔率的多孔陶瓷，采用浸渍和反应法负载氢氧化高钯催化剂。利用次甲基蓝模拟污水，并作为钯基催化剂催化次氯酸钠分解的标识物。研究了催化剂负载量、温度、次氯酸钠用量对催化剂降解次甲基蓝的影响。结果显示，多孔陶瓷负载的钯催化剂能有效催化次氯酸钠分解，极大地提高了次甲基蓝氧化褪色的速率，随温度升高，最终褪色所需时间急剧减少。在温度为40℃，催化剂量为0.4g，NaClO量为5mL，pH值为7.88的条件下，50mL浓度为10mg/L的次甲基蓝仅需要58分钟就能褪至无色。

Abstract:

Porous ceramics with a high open porosity were prepared by employing low-cost kaolin, talcum powder, and alumina as major raw materials, cement as curing agent, and hydrophobic activated carbon powders as foam stabilizing agent via direct foaming. PdOOH catalyst was loaded on porous ceramics via immersion and reaction method. Methylene blue was used as the simulated pollutant in sewage, and also used as the degradable agent when sodium hypochlorite was decomposed by the palladium-based catalyst. Effects of the loaded amount of catalyst, temperature, and the amount of sodium hypochlorite on the degrading speed of methylene blue were investigated. The results indicate that the palladium catalyst loaded on porous ceramics can effectively catalyze the decomposition of sodium hypochlorite, and significantly improve the color fading speed of methylene blue by oxidation. The time required for color fading drastically decreases with the increment of temperature. It only needs 58 min for methylene blue (10mg/L, 50 mL) to fade to colorless when the temperature, the amounts of catalyst and sodium hypochlorite, and pH value are 40 oC, 0.4 g, 5 mL and 7.88, respectively.