Abstract: Improved sol-gel has been used for preparing TiO₂ heterogeneous catalyst which uses Al₂O₃ as its carrier. Drilling wastewater COD as target degradation products, the effects of catalyst dosage, ozone concentration, pH and reaction time on COD removal by O₃/TiO₂/Al₂O₃ catalytic oxidation are investigated. The results show that comparied with O₃ and O₃/TiO₂ treatment processes separately, the wastewater COD removing rate is greatly improved by O₃/TiO₂/Al₂O₃ process, and alkalic pH environment is good for carrying on the TiO₂/Al₂O₃ catalytic ozonation process. Under the conditions as follows:the catalyst dosage is 3.75 g/L, ozone mass concentration 80 mg/L, and pH 9.4, and after 25 min of reaction time, the COD removing rate can reach 92.35%, wastewater COD decreases from 890 mg/L to about 68 mg/L, meeting the first class requirements of Wastewater Comprehensive Discharge Standard(GB 8978— 1996).

Key words: drilling wastewater, heterogeneous catalystic ozonation, ozone, TiO₂/Al₂O₃

摘要： 试验采用改进的溶胶-凝胶法制备了以Al₂O₃为载体的TiO₂多相催化剂，并以钻井废水COD为目标降解物，考察了催化剂投加量、臭氧浓度、pH和反应时间对O₃/TiO₂/Al₂O₃催化氧化去除COD的影响。结果表明：相比于单独O₃、O₃/TiO₂处理工艺，O₃/TiO₂/Al₂O₃明显地提高了对废水COD的去除率，且碱性pH环境利于TiO₂/Al₂O₃催化臭氧化反应的进行；在催化剂投加量为3.75 g/L，臭氧质量浓度为80 mg/L，pH 为9.4的条件下，反应25 min后，COD去除率可达92.35%，废水COD可从890 mg/L降至约68 mg/L，达到了《污水综合排放标准》（GB 8978—1996）的一级排放标准。

关键词: 钻井废水, 多相催化臭氧化, 臭氧, TiO₂/Al₂O₃

CLC Number: 

• X703.1