| P-tert-butyltoluene(PTBT) is a kind of organic intermediate which is an important raw material of manufacturing lilial. Thus it is significant that study the process of how to product p-tert-Butyltoluene by toluene and tert-butylchloride. Tert-butylchloride, which could be treated as the raw material of alkylation reaction, was made in continuous operation reaction unit in order to investigate both preparation conditions and purification conditions. It is stringent to develop a novel process since there were several problems existed in traditional process such as contamination and equipment erosion. In this paper, ionic liquid was regarded as catalyst in order to study its function in alkylation reaction between toluene and tert-butylchloride.Tert-butylchloride was manufactured by hydrogen chloride and tertiary butanol in continuous operation reaction equipment which contained HCl plant and reactor. Amount of tert-butylchloride would rise by means of controlling related reaction conditions and enhancing the equipment. The purity of product(tert-butylchloride) could arrive at99.9%on the condition that tert-butylchloride was washed by sulfuric acid and water, dehydrated by molecular sieve, rectified by rectification column(collecting cut fraction between51℃and52℃).Many kinds of ionic liquid (with Br(?)nsted acidity sites and Lewis acidity sites respectively) were prepared and utilized to catalyze the alkylation reaction in batch reactor so that their catalytic performance could be studied and suitable catalyst could be manufactured finally. Research showed that ionic liquid with Br(?)nsted acidity sites could not catalyze the alkylation reaction between toluene and tert-butylchloride whereas ionic liquid with Lewis acidity sites was able to catalyze the reaction apparently. However, selection of PTBT, which was catalyzed by various kinds of catalyst with Lewis acidity site, differed from each other due to the catalytic activity of catalyst, which was synthetized by different cation and anion, was different.The main research object, in this paper, was the ionic liquid composed of AlCl3and triethylamine hydrochloride. The composition of ionic liquid, amount of ionic liquid, reaction time, reaction temperature, molar ratio between toluene and tert-butylchloride, ability of regeneration were investigated respectively in the experiment in order to explore how those parameters affected the alkylation reaction. As a result, the best condition of manufacturing PTBT was listed as follows:the molar ratio between AlCl3and Et3NHCl was1.6; The amount of ionic liquid was10%of toluene; the molar ratio between toluene and tert-butylchloride was2, the reaction should conduct at20℃during10minutes. The conversion of tert-butylchloride could reach98%and the selection of PTBT could amount to82.5%simultaneously. Furthermore, the ionic.liquid could be reused by8times which still showed apparent catalytic performance.Trace amount of material with ability of electron donating (sulfur alcohol, sulfur ether, transition mental ion, nitromethane e.g.) was added into ionic liquid so that selection of PTBT could be enhanced. According to experimental results, ionic liquid which CuCl, CH3NO2or n-butyl mercaptan was added into increased the selectivity of PTBT evidently.Since both stability and property of catalyst would be affected substantially by impurities existed in industrial raw materials, the effect of water, tertiary butanol, ethyl tert-butyl ether was taken into account in the sight of their negative influence on ionic liquid. The results illustrated that both stability and catalytic performance of ionic liquid would be impaired by those impurities.Regeneration of inactive ionic liquid was carried out and the results demonstrated that activity of inactive ionic liquid could be restored by adding the fresh AICl3into the inactive catalyst. The ionic liquid, after regeneration, had similar catalytic activity and reusability compared with fresh catalyst. |
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