Catalytic Transformation of Bio-oil to Olefins with Molecular Sieve Catalysts

Catalytic conversion of bio-oil into light olefins was performed by a series of molecular sieve catalysts, including HZSM-5, MCM-41, SAPO-34 and Y-zeolite. Based on the light olefins yield and its carbon selectivity, the production of light olefins decreased in the following order： HZSM-5〉SAPO-34〉MCM-41〉Y-zeolite. The highest olefins yield from bio-oil using HZSM- 5 catalyst reached 0.22 kg/kgbio-oil with carbon selectivity of 50.7% and a nearly complete bio-oil conversion. The reaction conditions and catalyst characterization were investigated in detail to reveal the relationship between the catalyst structure and the production of olefins. The comparison between the pyrolysis and catalytic pyrolysis of bio-oil was also performed.

Deactivation mechanisms and anti-deactivation strategies of molecular sieve catalysts for NO_(x)reduction

Molecular sieve catalysts,owing to their unique chemical properties,are widely used as catalysts among various catalytic reactions.Abundant Br?nsted acid sites in molecular sieve catalysts usually enable active components to disperse well on the catalyst surface,and help to adsorb a large number of gas molecules to achieve maximum catalytic performance.Therefore,a variety of molecular sieve catalysts have been developed and used in the selective catalytic reduction of NO_(x)by NH_(3)(NH_(3)-SCR).For example,Cu molecular sieve catalysts such as Cu-SSZ-13 and Cu-SAPO-34 with wide temperature windows and stable structure are considered and applied as commercial catalysts for NO_(x)removal in diesel vehicles for a long time.Although molecular sieve catalysts possess many advantages,they still cannot avoid the serious deactivation caused by various factors in practical applications.In this review,reasons leading to the deactivation of molecular sieve catalysts for NO_(x)reduction in actual working conditions were concluded.The deactivation mechanisms of molecular sieve catalysts for NO_(x)reduction were analyzed and the corresponding anti-deactivation strategies were summarized.Finally,challenges and prospects of molecular sieve catalysts for NO_(x)reduction were also proposed.

Aluminum impregnated silica catalyst for Friedel–Crafts reaction：Influence of ordering mesostructure

Friedel–Crafts alkylation of benzene with linear chain ole fin(C_(10)–C_(14)),which is an important reaction of synthetic detergent,was studied via different catalysts of aluminum impregnated silica molecular sieves.AlCl_3 was immobilized on silica molecular sieves with different channel structures,hexagonal packing channels network(SBA-15,MCM-41),and disordered channel network(SiO_2,SiO_2-Gel) by impregnation.XRD and N_2 adsorption–desorption isotherms con firmed that the speci fic mesoporous structures were maintained for order channel network catalyst after impregnation.Catalytic activities were investigated under different conditions.The in fluences of channel structure were discussed.The results showed that catalyst based on mesoporous like SBA-15 had the highest catalytic activities and 2-LAB selectivity compared with other catalysts in this work.The highest 2-LAB selectivity was nearly 50% when 1-dodecene conversion was nearly 100%.At low 1-dodecene conversion or higher benzene/1-dodecene molar ratio,2-LAB selectivity was nearly 60%.