Conversion of methanol(MeOH) to 2,2,3-trimethylbutane(triptane) over zinc iodide(ZnI_2)catalyst was investigated in a closed batch reactor.Optimum operating parameters were searched and catalyst deactivation and regen...Conversion of methanol(MeOH) to 2,2,3-trimethylbutane(triptane) over zinc iodide(ZnI_2)catalyst was investigated in a closed batch reactor.Optimum operating parameters were searched and catalyst deactivation and regeneration behaviors were discussed.The fresh,spent and regenerated catalysts were characterized by XRD,TG and XRF measurements to elucidate the related mechanism.The experimental results showed that the triptane yield reached up to 12.2% under the process conditions,including a reaction temperature of 200℃,an initial pressure of 0.35 MPa,a reaction time of 2 h,and a Me OH to ZnI_2 molar ratio of 2.The catalyst was gradually deactivated after several run cycles.A small amount of iodine was lost and a certain amount of ZnO was formed on the deactivated ZnI_2 catalyst.Deactivation of the catalyst could be attributed to the reduction of ZnI_2 amount,resulted from iodine loss and formation of Zn O.It was firstly pointed out from our work that the deactivated catalyst could be well regenerated by the hydrogen iodide(HI) and the tert-butanol compensation method,wherein the latter was added as an initiator into the reaction system.The activity recovery of the deactivated(spent) catalyst might be related to the reformation of ZnI_2 and acceleration of the initiation step of this reaction.展开更多
文摘Conversion of methanol(MeOH) to 2,2,3-trimethylbutane(triptane) over zinc iodide(ZnI_2)catalyst was investigated in a closed batch reactor.Optimum operating parameters were searched and catalyst deactivation and regeneration behaviors were discussed.The fresh,spent and regenerated catalysts were characterized by XRD,TG and XRF measurements to elucidate the related mechanism.The experimental results showed that the triptane yield reached up to 12.2% under the process conditions,including a reaction temperature of 200℃,an initial pressure of 0.35 MPa,a reaction time of 2 h,and a Me OH to ZnI_2 molar ratio of 2.The catalyst was gradually deactivated after several run cycles.A small amount of iodine was lost and a certain amount of ZnO was formed on the deactivated ZnI_2 catalyst.Deactivation of the catalyst could be attributed to the reduction of ZnI_2 amount,resulted from iodine loss and formation of Zn O.It was firstly pointed out from our work that the deactivated catalyst could be well regenerated by the hydrogen iodide(HI) and the tert-butanol compensation method,wherein the latter was added as an initiator into the reaction system.The activity recovery of the deactivated(spent) catalyst might be related to the reformation of ZnI_2 and acceleration of the initiation step of this reaction.
