New sorbents for desulfurization by π-complexation:: Thiophene/benzene adsorption
New sorbents for desulfurization by π-complexation:: Thiophene/benzene adsorption
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DOI：
10.1021/ie0109657
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发表时间：
2002-05-15
影响因子：
4.2
通讯作者：
Yang, RT
中科院分区：
文献类型：
--
作者：
Takahashi, A;Yang, FH;Yang, RT
采用π络合法开发了新型液体燃料脱硫剂。研究了Ag-Y、Cu-Y、Na-Y、H-USY、Na-ZSM-5、活性炭和改性活性氧化铝等吸附剂对苯/噻吩的气相吸附等温线。与Na-Y相比，Cu-Y和Ag-Y在低压下吸附显著更大量的噻吩和苯，这是由于与Cu+和Ag+的π络合。分子轨道计算证实了π络合作用的相对强弱顺序为噻吩>苯和Cu+ > Ag+。π-络合的吸附热的实验结果与理论分子轨道预测非常吻合。Na-ZSM-5和活性炭在低压下也能吸附少量的噻吩和苯。在2.3 × 10（-5）atm的低压下，噻吩的吸附容量为0.92分子/Cu+和0.42分子/Ag+，并且遵循Cu-Y和Ag-Y的顺序，远大于Na-ZSM-5 >活性炭> Na-Y >改性氧化铝和H-USY。由纯组分吸附等温线计算的噻吩在苯上的分离因子（在低浓度噻吩时）呈现Ag-Y > Na-ZSM-5 > Cu-Y（接近活性炭）远大于Na-Y（接近改性活性氧化铝）远大于H-USY（接近改性活性氧化铝）的趋势。
New sorbents for the desulfurization of liquid fuels were developed using pi-complexation. Vapor-phase adsorption isotherms were investigated to understand the interaction between benzene/thiophene and various kinds of sorbents, including Ag-Y, Cu-Y, Na-Y, H-USY, Na-ZSM-5, activated carbon, and modified activated alumina. Compared to Na-Y, Cu-Y and Ag-Y adsorbed significantly larger amounts of, both thiophene and benzene at low pressures, as a result of pi-complexation with Cu+ and Ag+. Molecular orbital calculations confirmed that the relative strengths of pi-complexation lie in the order thiophene > benzene and Cu+ > Ag+. The experimental heats of adsorption for pi-complexation are in excellent agreement with theoretical molecular orbital predictions. Na-ZSM-5 and activated carbon could also adsorb small amounts of thiophene and benzene at low pressures. The sorbent capacities for thiophene at the low pressure of 2.3 x 10(-5) atm were 0.92 molecule/Cu+ and 0.42 molecule/Ag+ and followed the order Cu-Y and Ag-Y much greater than Na-ZSM-5 > activated carbon > Na-Y > modified alumina and H-USY. The separation factors of thiophene over benzene (at low concentrations of thiophene) calculated from pure component adsorption isotherms exhibited the trend Ag-Y > Na-ZSM-5 > Cu-Y approximate to activated carbon much greater than Na-Y much greater than H-USY approximate to modified activated alumina.