| In the coking benzene, there are some impurities hardly to be removed using the traditional method , and they are also the main barriers for the coking benzene utilization in many chemical industry . The removal of organic sulfur and olefin are the key technology in the coking benzne purification process.In fact, the oxidation process were a promising method in the removal of the coking benzene impurities, and becoming the research hot spot gradually. In this paper, the impurities in a coking benzene were analysis one by one, then the removal of them was studied by used the potassium permanganate as the oxidiant.Firstly, the coking benzene sample was undergoing the analyssis with the GC-MS and UV, the results was that no any significant impurities could be detected from the GCMS analysis. The phenol in the coking benzene could be qualitatively analyzed by the UV. After the treatment by 30% NaOH solution, the phenol could be partially removed .Secondly,The olefin in the coking benzene were quantitatively analyzed by the potentiometric titration, the bromine price of coking benzene sample was 0.0423gBr·100mL-1. Acoording to compared the change of the bromine price, the olefin contained in coking benzene could be removed 5060% after the oxidation processes by potassium permanganate solution. Raising the temperature could help lowering the bromine price and acid washing colormetric analysis of the coking benzene.Lastly, the amounts of thiophene and the total sulfur were mesured by GC-FPD and microcoulomb meter respectively, thiophene was removed from coking benzene by the oxidation and chlorination processing with KMnO4 and the mixtures of KMnO4 and FeCl3·6H2O respectively,the effects of the removal ratio had been discussed in terms of the time ,temperature ,concentration and the amounts of FeCl3·6H2O. Thiophene could be removed a little with KMnO4 solution alone. increasing reaction time and rising temperature, the ratio of the removed thiophene was little arise , which could not reach up to the effection of the deep desulfurization.Prolonging treating time had evidented effect on chloridize removal of thiophene. The experimental results indicated that,the coking benzene sample containing the thiophene sulfur with the content of 71.7mg? L-1 could be removed completely, the volume ratio of the coking benzene,the KMnO4 (45g·L-1),the FeCl3·6H2O (45g·L-1) were under the 5:2:1 and the treating time was 4h.Increasing amounts of the FeCl3·6H2O has evidented effect on chloridize removal of thiophene. Under the same condition,when the concentration of the FeCl3·6H2O increase from 12g·L-1 to 45g·L-1, the ratio of thiophene removal can increase from 35.09 % to 100 %. In the analysis processing, chlorine substitutes'molecular structure were determined by GCMS , the mechanism of removal thiophene was studied and it was proved through theoretical analysis. The mechanism of chloridize removal of thiophene could be expressed with the below equations:...
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