Abstract:

A kind of fixed bed ozone catalytic oxidation equipment with reflux was designed, and the properties of α-Fe₂O₃/γ-Al₂O₃ catalyst prepared by impregnation method was characterized, then the performance of ozone catalytic oxidation for the concentrated water of coal chemical reverse osmosis was studied by α-Fe₂O₃/γ-Al₂O₃ catalyst in the fixed bed equipment with reflux. The results showed that the specific surface area, average pore diameter, total pore volume and the active component α-Fe₂O₃ content of the α-Fe₂O₃/γ-Al₂O₃ were 161.74m²/g, 10nm, 0.4533cm³/g and 8.73%, respectively. With the increase of catalyst loading height, ozone concentration and hydrogen peroxide dosage, the COD removal rate of the reverse osmosis concentrated water increased firstly, and then decreased, the reflux could significantly increase the rate. The suitable values of the catalyst loading height in the equipment, ozone concentration, dosage of hydrogen peroxide and reflux ratio were 350mm, 300mg/L, 150mg/L and 50%, respectively, which the COD removal rate of ozone-catalyzed oxidation reverse osmosis concentrated water was as high as 74.33%. Most of the dissolved organic matter and humic acids in the reverse osmosis water from coal chemical industry had been decomposed after ozone catalytic oxidation.

Key words: ozone, catalytic oxidation, reflux, fixed-bed, reverse osmosis concentrated water

摘要：

设计了一种具有回流的固定床臭氧催化氧化反应装置，对浸渍法制得的α-Fe₂O₃/γ-Al₂O₃催化剂的性能进行了表征，并利用其在回流固定床反应装置中对煤化工反渗透浓水的臭氧催化氧化性能进行了研究。结果表明：α-Fe₂O₃/γ-Al₂O₃的比表面积、平均孔径、总孔容和活性组分α-Fe₂O₃含量分别为161.74m²/g、10nm、0.4533cm³/g和8.73%。反渗透浓水COD去除率随催化剂装填高度、臭氧投加浓度和过氧化氢投加量的增加而均呈现为先增加、后降低的变化趋势，回流可显著地提高废水COD去除率，适宜的催化剂装填高度、臭氧投加浓度、过氧化氢投加量和回流比分别为350mm、300mg/L、150mg/L和50%，臭氧催化氧化反渗透浓水的COD去除率达74.33%。煤化工反渗透浓水中大部分溶解性有机物和腐殖酸类物质均被臭氧催化氧化分解。

关键词: 臭氧, 催化氧化, 回流, 固定床, 反渗透浓水