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Various dealuminum methods of zeolite Beta to generate the jet fuels by converting isobutyl alcohol has been investigated in detail. And related factors of the zeolite catalyst such as acid site, pore structure, and pore size which can influence reactive activity, were also studied utilizing XRD, SEM, XRF, Nitrogen adsorption-desorption, NH3-TPD, Py-FTIR, and 27Al solid-state NMR. Removal of extra-framework aluminum or part of framework aluminum by hydrochloric acid dealumination, is able to improve the diffusion property of the products in the channel of zeolite Beta via increasing the ratio of Lewis/Bronsted. Consequently, isobutyl alcohol can be quantitatively oligomerized over dealuminated zeolite Beta with the selectivity of C8−16 exceeding 50 % at a conversion of 98 %. Moreover, the deactivated catalyst can be easily regenerated by calcining it in flowing air. High conversion, high jet fuels selectivity, and facile regeneration make it an attractive potential catalyst for isobutyl alcohol oligomerization reaction.

Spinel-like ZnFe2O4 is tailor-made synthesized for catalyzing CO2 hydrogenation, achieving an ultra-high yield (1858.1 g kgcat-1 h-1) of full spectrum alkenes in a three-stage reactor system. This study provides rational design concepts from catalyst to equipment amelioration by combining promoter regulation and ex situ water removal, efficiently catalyzing CO2 into valuable chemical feedstocks with industrial potential.

Cu/ZnO catalysts with varied Cu/(Cu + Zn) molar ratios were prepared by a facile solid-state method. The Cu/(Cu + Zn) molar ratio displayed a significant effect on the oxygen vacancy formation of the calcined catalysts, thereby influencing the CuO-ZnO interaction and the reducibility of CuO. The Cu/(Cu + Zn) molar ratio also exhibited a significant effect on Cu

Spinel-like ZnFe

Binary Cu/ZnO catalysts were prepared by solid-state method and tested for vapor-phase low-temperature methanol synthesis from CO2-containing syngas. The influence of H2C2O4/(Cu + Zn) molar ratio on the physicochemical properties and the corresponding catalytic activity was systematically studied. The space time yield (STY) of methanol exhibited a linear relationship with the Cu0 surface area, and increased linearly by enhancing the number of strongly acidic sites or moderately basic sites. The effects of various parameters on the methanol synthesis reaction were also investigated. C4-Red catalyst (H2C2O4/(Cu + Zn) = 4/1) exhibited the maximum turnover frequency (TOF, 11.4 × 10−3 s−1) and STY values (456.3 g/kg h−1), due to the larger Cu0 surface area, greater specific surface area, more strongly acidic sites and moderately basic sites. The strengthened Cu-ZnO interaction, superior CO and H2 adsorption capability as well as higher adsorbed CO and H2 amount also contributed to increasing the catalytic performance of C4-Red catalyst.

Effects of different mordenite (MOR) zeolite synthesis conditions, such as salt additive, hydrothermal time, hydrothermal temperature, and ultrasonic assistance, on dimethyl ether (DME) carbonylation were studied systematically in this work. Salt as additives being introduced into hydrothermal system obviously promoted the crystallinity and morphology of MOR. With the increase of hydrothermal time and temperature, a better crystallinity was obtained on the sample. However, a higher hydrothermal temperature of 180 °C led to a slightly decreased crystallinity. The MOR catalyst with NaCl as the additive and hydrothermal treatment at 130 °C for 48 h realized a better DME carbonylation activity with 50% DME conversion and almost 100% methyl acetate (MA) selectivity. In addition, H-MOR-UT, a MOR zeolite prepared with the assistance of ultrasonic treatment, showed a special morphology consisting of lots of MOR nanosheets with a width of around 70 nm. Here, this H-MOR-UT realized an enhanced catalytic stability and the highest DME conversion of 70%, about 5 times higher than the reference MOR zeolite prepared by traditional method. The strikingly excellent catalytic performance was attributed to its more acid content, stronger acid strength and smaller grain size.

This work describes a novel route for the fabrication of heteroatom doped iron-based catalysts (spinel-like structure) through urea self-combustion method, and catalytic performances over these self-combustion catalysts are investigated in detail. It is found that catalytic performances are affected by the properties of doped metals. Owing to the high methanation activity of Ni and Co, NiFe2Ox and CoFe2Ox catalysts present high CH4 selectivity compared to Fe2O3 catalysts. MgFe2Ox exhibits high olefin hydrogenation ability. By contrast, the utilization of Cu and Zn promotes catalytic activity and olefins selectivity via regulating surface CO2 adsorption and carbides content. Among these spinel catalysts, the ZnFe2Ox catalyst shows the best CO2 hydrogenation performance. Enhanced CO2 adsorptions as well as active species of carbides result in the benign hydrogenation behavior. Meanwhile, the effects of Zn/Fe molar ratio are also investigated. It is worth noting that the catalytic performance can be improved regardless of the added amount of Zn promoter. Nevertheless, the catalytic performance reaches the best level when the Zn/Fe molar ratio equals 1/2. The proposed method provides a new strategy different from traditional catalyst preparation process for catalytic hydrogenation of CO2 into highly valuable products.