ZEO-1,the first stable aluminosilicate zeolite with extra-large pores,marks a great breakthrough in the zeolite community after decades of exploration and endeavors,opening possibilities for processing bulky substrate...ZEO-1,the first stable aluminosilicate zeolite with extra-large pores,marks a great breakthrough in the zeolite community after decades of exploration and endeavors,opening possibilities for processing bulky substrates.However,the long synthesis cycle and relatively low reproducibility hinder the wide application of this intriguing material.This work developed a‘deficient fluoride approach’for ZEO-1 zeolite synthesis by adding a small amount of fluoride to induce a charge imbalance between the OSDA and fluoride.This approach significantly accelerates crystallization(15 times faster than the reported method)and achieves higher reproducibility than the originally reported protocol.Crystallization kinetics studies demonstrate the accelerating effect of stoichiometrically deficient fluoride anions on the nucleation and crystallization process.The ZEO-1 zeolites synthesized via the‘deficient fluoride approach’show catalytic activity for phenol alkylation with tert-butyl alcohol comparable to that of ZEO-1LCS,but the products are evenly distributed,suggesting that more Brønsted acid sites might have been successfully introduced in the 16 MR channels.This work provides an incentive for feasible academic study and application of ZEO-1.展开更多
Zeolite crystals are often subjected to different post-synthetic chemical treatments prior to being used in catalytic or separation processes.We highlight a novel non-chemical post-synthetic approach to overcome diffu...Zeolite crystals are often subjected to different post-synthetic chemical treatments prior to being used in catalytic or separation processes.We highlight a novel non-chemical post-synthetic approach to overcome diffusion limitations in zeolite catalysts and boost their catalytic activity by applying a constant pressure to downsize micron-sized zeolite crystals to sub-micron-sized particles.The method is highlighted by treating a ZSM-5 with hydraulic pressure.The physicochemical characterization of the resulting material shows a substantial reduction in the size of the crystals without altering their native properties(crystallinity,porosity,acidity).ZSM-5 crystals processed in such a way exhibit improved catalytic activity in the Methanol-to-Olefins(MTO)reaction,where the cumulative amount of methanol converted is two and a half times greater than their parent.This is ascribed to the enhanced molecular diffusion of the pressure-treated crystals,which is supported by breakthrough curve analysis.展开更多
基金The ZeoMat Group acknowledges the starting grant provided by the Qingdao Institute of Bioenergy and Bioprocess Technology and the support from the Shandong Energy Institute(SEI S202107)P.L.acknowledges the support from the Qingdao New Energy Shandong Laboratory of International Cooperation Project(QNESL ICP 202305)V.V.and P.L.acknowledge the collaboration within the Sino-French International Research Network‘Zeolites’framework.The authors are indebted to Yida Zhou and Shutao Xu from Dalian Institute of Chemical Physics for collecting the 19F NMR data.
文摘ZEO-1,the first stable aluminosilicate zeolite with extra-large pores,marks a great breakthrough in the zeolite community after decades of exploration and endeavors,opening possibilities for processing bulky substrates.However,the long synthesis cycle and relatively low reproducibility hinder the wide application of this intriguing material.This work developed a‘deficient fluoride approach’for ZEO-1 zeolite synthesis by adding a small amount of fluoride to induce a charge imbalance between the OSDA and fluoride.This approach significantly accelerates crystallization(15 times faster than the reported method)and achieves higher reproducibility than the originally reported protocol.Crystallization kinetics studies demonstrate the accelerating effect of stoichiometrically deficient fluoride anions on the nucleation and crystallization process.The ZEO-1 zeolites synthesized via the‘deficient fluoride approach’show catalytic activity for phenol alkylation with tert-butyl alcohol comparable to that of ZEO-1LCS,but the products are evenly distributed,suggesting that more Brønsted acid sites might have been successfully introduced in the 16 MR channels.This work provides an incentive for feasible academic study and application of ZEO-1.
基金supported by the Industrial Chaire EcoGas,funded by TotalEnergies and the Normandy region.
文摘Zeolite crystals are often subjected to different post-synthetic chemical treatments prior to being used in catalytic or separation processes.We highlight a novel non-chemical post-synthetic approach to overcome diffusion limitations in zeolite catalysts and boost their catalytic activity by applying a constant pressure to downsize micron-sized zeolite crystals to sub-micron-sized particles.The method is highlighted by treating a ZSM-5 with hydraulic pressure.The physicochemical characterization of the resulting material shows a substantial reduction in the size of the crystals without altering their native properties(crystallinity,porosity,acidity).ZSM-5 crystals processed in such a way exhibit improved catalytic activity in the Methanol-to-Olefins(MTO)reaction,where the cumulative amount of methanol converted is two and a half times greater than their parent.This is ascribed to the enhanced molecular diffusion of the pressure-treated crystals,which is supported by breakthrough curve analysis.
