Gas chromatography and gas chromatography-mass spectrometry were used to analyze the non-aromatics in the feedstock of the toluene disproportionation unit of Shanghai Petrochemical Company Limited, SINOPEC (SPC). The effects of the non-aromatics in the feedstock on the toluene disproportionation and the aromatics transalkylation were investigated. The qualitative analysis showed that the non-aromatics in the feedstock included C3-5 alkanes, C7-10 cycloalkanes with five or sixmembered ring, and C10 and C11 alkanes. And the mass fraction of the non-aromatics in the feedstock was 2.90％. The toluene disproportionation and the aromatics transalkylation for the SPC feedstock indicated that the feedstock conversion was obviously lower than that of conventional feedstock after the reactions under the conditions of 400 ℃, 72 h, WHSV 2.5 h- 1, n ( H2 ): n (hydrocarbon) 3.0 and 3.0 MPa. To get the same conversion as the conventional feedstock the reaction temperature for the SPC feedstock should be heightened by 20 ℃, which would resulted in shortening of the catalyst lifetime. The existence of large amount of heavy non-aromatics in the SPC feedstock significantly affected the catalyst lifetime also.%采用气相色谱-质谱联用和气相色谱相结合的方法对中国石化上海石油化工股份有限公司甲苯歧化单元原料中的非芳烃进行了定性、定量分析;并考察了原料中的非芳烃对甲苯歧化与芳烃烷基转移反应的影响.定性分析结果表明,该原料中的非芳烃组分非常复杂,包括C3-5的低碳烷烃、以五元环和六元环为主的C7～10环烷烃以及少量的C10和C11链烷烃;定量分析结果表明,非芳烃的质量分数(相对于原料)达到2.90%.甲苯歧化与芳烃烷基转移反应实验结果表明,在反应温度400℃、液态空速2.5 h-1、氢烃摩尔比3.0、反应压力3.0 MPa、反应时间72 h的条件下,该原料的转化率明显低于常规原料,要维持相同转化率,反应温度大约需提高20℃;该原料因含有较多的重质非芳烃,在较大程度上影响了催化剂的使用寿命.
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