Research On Technology And Mechanism In The Process Of Quinoline SCF Extraction

Quinoline is an important chemical raw material,except the Skraup synthesis to obtain quinoline,it mainly exists in wash oil fraction of coal tar. It is important to study the new technology of quinoline separation in the wash oil fraction. In this paper, the common extraction and supercritical fluid extraction had been carried out on wash oil which had been treated as secondary product of coking. The influence of the kinds of extracting agent, the density of extracting agent, the ratio of extracting agent and distillate had been studied during common extraction proceeding. In the supercritical fluid extraction, the alcohol was chose as the extracting agent innovative. The influence of temperature, pressure, density of quinoline, cosolvents was studied in the supercritical extraction proceeding. The mechanism of each factor had been approached. This study is treated as the foundation of further study of wash oil processing, and quinoline processing especially. The characteristic work of this study are:In the common extraction proceeding, the pH and density of extracting agent had a great effect on extraction efficiency. Avoiding indole and pyridine's secondary reactions could also increase the efficiency of quinoline extraction. To obtain 64.78% quinoline in the raw quinoline production ,the best agent is ammonium bisulfate that massfraction is 20% mixing up with distillate in the ratio of 5/8.The alcohol was chose as the agent innovative. The influence of temperature, pressure, density of quinoline, cosolvents was studied in the supercritical extraction proceeding. Draw a conclusion that the optimum conditions of temperature is 260℃,pressure is 7.3MPa. The conclusion shows that the extraction efficiency is greater when the pressure is bigger, and it will quickly become lower when the pressure is bigger than the optimum condition. Temperature also has a great influence on the extraction efficiency.In this paper, the influence of cosolvents on supercritical extraction proceeding has been studie. The conclusion shows that the extraction efficiency could be increased by adding cosolvents. Best operational factors is 1.847. The influence of two kinds of cosolvents is pentane>methanol.