Kinetic and thermodynamic studies on adsorption of thiophene and benzothiophene onto AgCeY Zeolite

Dynamic catalytic adsorptive desulfurization of real diesel over ultra‐stable and low‐cost silica gel‐supported TiO2

“…The negative value of ΔG indicates the spontaneous nature of sorption of sulfone over the adsorbent, and a negative ΔH indicates an exothermic adsorption . The ΔH (33.4 kJ/mol) of sulfone adsorption over 15% TiO 2 /C‐SiO 2 ‐2 is higher than the calculated heat of physisorption of BT on AgCeY Zeolite reported by Song et al (∼26 kJ/mol), and lower than the heat of chemisorption of BT on NA‐ZSM‐5 reported by Yang and coworkers (76–79 kJ/mol), as Na promoted the interaction between sulfur atom and the adsorbent. The sulfur adsorption is not as strong as chemisorption, which is plausible for reversible and ease regeneration later in multiple adsorption‐regeneration cycles after the adsorbent saturated.…”

“…Liu reported the Langmuir equilibrium constant can be reasonably used for calculated free energy change for adsorption, while the adsorbates were neutral or with weak charge. The Langmuir equilibrium constant has been employed often for calculation of Δ G using the equation in adsorption studies . The thermodynamic parameters can be calculated using the following equation …”

Avaliação da remoção adsortiva do tiofeno de uma gasolina modelo utilizando ZSM-35 impregnada com molibdênio

“…Neste processo a carga que entra no reator é composta por naftas ou destilados, oriundos de outras unidades de processamento tais como a destilação atmosférica, destilação a vácuo ou unidade de craqueamento. O processo de hidrodessulfurização é altamente eficiente na remoção de tióis, sulfetos e dissulfetos, mas é menos eficiente para tiofenos e derivados de tiofeno [5][6][7]1]. Assim, os compostos de enxofre que permanecem nos combustíveis de transporte são tiofeno, benzotiofeno, dibenzotiofeno e seus derivados alquilados [1].…”

“…Sendo assim, a viabilidade técnica de processos alternativos e/ou complementares à HDS é uma crescente no meio científico, sendo que os principais processos alternativos e/ou complementares de dessulfurização estudados visam a aplicação de processos biotecnológicos [9][10][11], utilização de processos oxidativos [12][13][14], e a aplicação de processos adsortivos utilizando diferentes materiais adsorventes [2,5,15]. A dessulfurização adsortiva recebe destaque por ser um dos métodos que utiliza condições operacionais de temperatura e pressão mais brandas [6].…”

Removal of sulphur from model gasoline by CuAgY zeolite: equilibrium, thermodynamics and kinetics

“…Besides experimental studies, mathematical model analysis is a practical and efficient way to elaborate the chemical processes and equipment in detail. Song et al 34,35 investigated the model of adsorption kinetics and adsorption equilibrium of TP and BT in model fuel on AgCeY and Cu I-Ce IV Y. They found that the Langmuir isotherm and the pseudo-rst-order model exhibited the best ts of experimental data, and the intra-particle diffusion was not the rate controlling step.…”