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The nitration 's the regioselective nitration reaction a hot research topic , the thesis Nitration of toluene substrate major study of of different nitrification system , temperature , nitrification strength , catalysts and their use of factors such as its nitrification area selectivity . Toluene nitration generally generate 60% ??of o-nitrotoluene , 4% of nitro toluene , 36% isomers of nitrotoluene three , currently on the market , nitrotoluene nitrotoluene has considerable economic value , how to improve nitrotoluene nitrotoluene formation ratio has become more practical issues . The main purpose of this paper is how to increase the proportion of generation nitrotoluene nitrotoluene . The paper by a large number of experiments , Regioselective Nitration of toluene in sulfuric acid medium , a certain degree of research . The results show that , in the mixed acid - phosphoric acid system H2S04 : N205 : P205 = 0.2:9.1:2.5 reaction temperature 60 ℃ between the nitrotoluene generation ratio of 4.7 % , O / P value of 1.62 . Sulfate - urea nitrate system , by adding a certain amount of urea nitrate solid study the impact of the temperature and the amount of sulfuric acid to the proportion of each product in the nitration of toluene , wherein the ratio of m-tolyl compared to a 1.2% increase in the industrial production reached 5.2 %, while the O / P value of 1.85. In the amide -based compound as a catalyst under the conditions , by adding a certain amount of the amide compound to study the impact of temperature, nitrification and amides substance amount on the proportion of each product in the nitration of toluene . After adding N, N- dimethylformamide was catalyzed the formation ratio of the nitrotoluene of 4.3 % o / P value dropped to 1.26 ; adding carboxamide catalytic the nitrotoluene generation ratio of 5.3 % , O, / P = 1.59; joining acetamide catalytic nitrotoluene ratio of 4.2 % , the O / P value of 1.48 ; ionic liquids under catalytic conditions , to study the temperature ionic liquids by adding a certain amount of nitrification strength and ionic liquids of toluene nitration product ratio of the amount of . Addition of ionic liquid [ p - SABPy HS04 the nitrotoluene generation proportion increased to 5.3% , the O / P value can be reduced to 1.27 . Among them , the use of sulfuric acid - urea nitrate system with amides catalyzed a new attempt to provide a reliable basis for the nitration of toluene industrial applications , has important guiding significance .
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