【作者】 吴爱明；

【导师】 戴友芝；

【作者基本信息】 湘潭大学 ， 环境工程， 2007， 硕士

【摘要】 炼油碱渣是石油炼制工业进行油品碱洗精制时产生的废碱液,含有酚类物质和有机硫化物等大量有毒有机物,生物降解性差,常规处理效果不理想,给环境造成严重污染。本文为解决中国石油化工股份有限公司长岭分公司炼油碱渣废水处理的技术难题,对湿式氧化及其强化处理工艺进行了研究,重点对催化湿式氧化法处理炼油碱渣废水催化剂的制备及其处理碱渣废水性能进行了研究,并对Mn基催化剂催化湿式氧化处理碱渣废水反应机理进行初探。湿式氧化法处理炼油碱渣废水研究表明:氧分压与处理效果呈正相关,当氧分压达2.0MPa即理论需氧量的1.18倍时,COD去除率达71.43%,且当供氧量不低于理论需氧量的0.59倍时,可从根本上解决结焦问题;采用酸化回收—湿式氧化组合工艺,酸化后COD去除71.9%[0],后续湿式氧化COD去除40.7%,总COD去除率为83.3%;采用酸化回收（后调节pH）—湿式氧化（+双氧水）组合工艺,经酸化（后调节pH）后废水COD去除78.1%[0],后续湿式氧化COD去除率提升至74.9%[0],总COD去除率高达94.4%;加入催化剂后,湿式氧化效果有明显提高。研制出适合碱渣废水的湿式氧化催化剂MnO_x/γ-Al₂O₃和MnOx-CeO_x/γ-Al₂O₃,MnO_x/γ-Al₂O₃对碱渣废水处理表现出较高的活性及稳定性,稀土元素Ce的加入则进一步提高了其性能。催化剂表征结果:处理碱渣废水后催化剂表面存在较多的有机官能团,结构中存在MnCO3和Al₄₅O₄₅（OH）₄₅Cl。Mn基催化剂催化湿式氧化处理炼油碱渣废水,当氧分压2MPa,反应温度220℃,催化剂用量2g/L时,废水COD去除率达91.33%;催化剂重复使用3次,COD去除率保持在85%以上,再生后催化剂活性提升1.83%,催化剂具有较好的稳定性。本文还对催化湿式氧化反应机理进行初步探讨,从理论上得出高的氧分压有利于提高反应速率;而锰负载量过高或者催化剂的投加过量时会抑制氧化反应,产生负催化作用;掺杂CeO₂可提高MnO_x/γ-Al₂O₃催化剂催化活性及稳定性。更多还原

【Abstract】 Refinery spent caustic is a kind of spent alkali liquor produced in refinery industry of petroleum. The content of toxic organic compound such as phenol and organic is very high in the petrochemical spent caustic wastewater which results in the poor biodergradation, and poor performance of conventional treatment process and exerts a serious pollution on the environment. For solving the technical problems of refinery spent caustic of Changling branche of China Petrochemical Corp. This paper investigated the technology, the catalyst properties of treating refinery spent caustic wastewater in wet oxidation, and explored wastewater treatment mechanism of the reaction of wet oxidation catalyst.The study of Wet oxidation of refinery spent caustic wastewater was found: oxygen partial pressure was positively correlated with the effect of the treatment. When oxygen partial pressure increased to 2.0 MPa which is 1.18 times of the theory value, 71.43% COD removal efficiency can be acquired. At the same time, we founded, when the amount of oxygen which is not lower than 0.59 times of the theoretical strength, the problem of coking can be fundamentally resolved. 83.3% total COD removal rate was obtained by the combination process of acidification-wet oxidation for disposal refinery spent caustic wastewater; while 94.4% total COD removal rate was got by the assembled process of acidification-wet oxidation for treating refinery spent caustic wastewater. The effects of wet air oxidation was obviously improved, when homogeneous metal catalysts was Added.In this paper, MnO_x/γ-Al₂O₃, MnO_x-CeO_x/γ-Al₂O₃ and manganese oxides were studied for suitable refinery spent caustic wet oxidation. The results indicated that MnO_x/γ-Al₂O₃ showed high activity and stability in the system, the adding of Ce further improve its performance. Catalyst characterization results: it can been seen that the reaction of catalyst surface has more organic functional; and reaction catalyst phase of the changes reaction catalyst structure exists MnCO₃ and Al₄₅O₄₅（OH）₄₅Cl.This paper study the base of Mn catalyst for treating the refinery spent caustic wastewater, The removal efficiency of COD was 91.33% with the dose of catalyst 2.0 g/L at reaction temperature of 220℃and oxygen partial pressure of 2.0 MPa. More than 85.0% of COD removal rate can maintain to 10%MnO_x/γ-Al₂O₃ catalyst reused three times, and its catalytic activity was increased 1.87% by regeneration; The results indicated that the reusable catalyst can restored a high activity. and reached good stability.The mechanism of catalytic wet oxidation reaction was explored, high oxygen partial pressure can effectively raise the rate of reaction in theoretics, while loading and manganese catalyst too high or excessive dosage will inhibit oxidation reactions and produce negative catalyst, and adding CeO2 can enhance the activity and stability of MnOx/γ-Al₂O₃ catalyst.更多还原