【作者】 赵强；

【导师】 雷晓东；

【作者基本信息】 北京化工大学 ， 化学工程与技术， 2011， 硕士

【摘要】 噻吩类化合物是一种存在于含硫废水和燃料中的有机硫化物。废水中的硫化物具有毒性、腐蚀性,燃料中的硫化物经过燃烧会产生SOx等大气污染物。如果不将其脱除,势必会对生态环境造成严重污染,从而危及到人类的生存。本文利用成核晶化隔离法和共沉淀法分别制备出的碳酸根和十二烷基硫酸钠(SDS)插层的水滑石(LDH)作为吸附剂来脱除水相中的噻吩。吸附结果表明两种材料对水中噻吩具有不同的吸附特性。对于Zn2Al-CO3LDH,需要将溶液pH值控制在6-8。在吸附温度为25℃时,对800 ppm的噻吩溶液最大去除率可达88.7%,吸附量达354.80 mg/g；对于SDS-LDH, pH值不需要控制在特定的范围。在吸附温度为25℃时,最大去除率可达91.4%,吸附量达146.24 mg/g。对这两种材料的吸附行为的动力学研究表明化学吸附在吸附过程中起着主导作用。本文研究了利用成核晶化隔离法制备出的Zn3Al-LDHs和Ni3Fe-LDHs对正庚烷溶液中噻吩的吸附性能。发现Ni3Fe-CO3 LDH具有最高的去除率和吸附容量。在温度为40℃时,Ni3Fe-CO3 LDH对500 ppm噻吩的去除率最高可达26.8%,吸附量最高可达8.62 mg/g。在50℃下于空气中活化60 min,再生产物的吸附量下降程度最低。经过三次循环再生利用,吸附量没有大幅度下降,表明Ni3Fe-CO3 LDH是一种较稳定的噻吩吸附剂。更多还原

【Abstract】 Thiophene compounds is a kind of typical organic sulfur compounds, which consist abundantly in many fields, such as fuels, industrial effluents. Thiophene compounds which consist in the industrial wastewaters are toxic substances and have corrosive action. Thiophene compounds in transportation fuels are a significant source of atmospheric pollution by sulfur oxides. There will be a great harm to the health of human beings and the environment, if thiophene compounds not be eliminated.In our research, the Zn2Al-CO3 LDH was synthesized by using a new method involving separate nucleation and aging steps, and the dodecylsulfate intercalated hydrotalcite (SDS-LDH) was synthesized by using the co-precipitation method. The two materials have been used to remove thiophene from aqueous solution, It was noticed that the adsorption behavior of thiophene on them was very different. The adsorption behavior of Zn2Al-CO3 LDH was obviously influenced by the pH, with the best removal efficiency in the pH range of 6.00 to 8.00. When the temperature was 25℃, the initial thiophene concentration was 800 ppm, the highest removal rate was 88.7% and the maximum value of adsorption capacity was 354.8 mg/g. For SDS-LDH, the adsorption process was found to be pH-independent, which could be used in a wide pH range. When the temperature was 25℃, the initial thiophene concentration was 800 ppm, the highest removal rate was 91.4% and the maximum value of adsorption capacity was 146.24 mg/g. The adsorption kinetics research of the two materials indicated the chemisorption mechanism being the rate-determining step, not just diffusion process.The Zn3Al-LDH and Ni3Fe-LDH were synthesized by using a new method involving separate nucleation and aging steps. These materials have been used to remove thiophene from n-heptane solution. It was observed that Ni3Fe-CO3 LDH was the best adsorbent, because it had the highest removal rate and the maximum value of adsorption capacity. So we have made further researches on adsorption of thiophene from n-heptane solution by Ni3Fe-CO3 LDH. The results indicated that the highest removal rate was reached after 120 min at 40℃. The highest removal rate was 26.8% and the maximum value of adsorption capacity was 8.62 mg/g. The optimum dosage for Ni3Fe-CO3 LDH was 20 g·L-1 respectively. The regeneration of adsorbent was also studied. The results showed that 50℃and 60 min was the best condition for regeneration of adsorbent. The adsorption capacity had only reduced a little when regeneration three times.更多还原