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Up to now, the member of zeolite family has expanded to more than 230. However, only little part of them have been reported as catalysts used in reactions. Discovering potential zeolites for reactions is significantly important, especially in industrial applications. A carbonylation zeolite catalyst Al-RUB-41 has special morphology and channel orientation. The 8-MR channel of Al-RUB-41 is just perpendicular to its thin sheet, making a very short mass-transfer distance along 8-MR. This specific nature endows Al-RUB-41 with efficient catalytic ability to dimethyl ether carbonylation reaction with beyond 95% methyl acetate selectivity. Compared with the most widely accepted carbonylation zeolite catalysts, Al-RUB-41 behaves a much better catalytic stability than H-MOR and a greatly enhanced catalytic activity than H-ZSM-35. A space-confined deactivation mechanism over Al-RUB-41 is proposed. By erasing the acid sites on outer surface, Al-RUB-41@SiO2 catalyst achieves a long-time and high-efficiency activity without any deactivation trend.

Reduction process is a key step to fabricate metal-zeolite catalysts in catalytic synthesis. However, because of the strong interaction force, metal oxides in zeolites are very difficult to be reduced. Existing reduction technologies are always energy-intensive, and inevitably cause the agglomeration of metallic particles in metal-zeolite catalysts or destroy zeolite structure in severe cases. Herein, we disclose that zeolites after ion exchange of ammonium have an interesting and unexpected self-reducing feature. It can accurately control the reduction of metal-zeolite catalysts, via in situ ammonia production from ‘ammonia pools’, meanwhile, restrains the growth of the size of metals. Such new and reliable ammonia pool effect is not influenced by topological structures of zeolites, and works well on reducible metals. The ammonia pool effect is ultimately attributed to an atmosphere-confined self-regulation mechanism. This methodology will significantly promote the fabrication for metal-zeolite catalysts, and further facilitate design and development of low-cost and high-activity catalysts.

The effects of particle concentration and size on hydrodynamics and mass transport in a slurry bubble column were experimentally studied. With increasing particle concentration, the averaged gas holdup, gas holdup of small bubbles and gas-liquid volumetric mass transfer coefficient decreased, while the gas holdup of large bubbles increased slightly. With increasing particle size, the averaged gas holdup and kla remained unchanged when the particle size increased from 55 to 92 m, but decreased significantly when the particle size was further increased to 206 m. A liquid turbulence attenuation model which could quantitatively describe the effects of particle concentration and size was first proposed. Semi-empirical correlations were obtained based on extensive experimental data in a wide range of operating conditions and corrected liquid properties. The gas holdup and mass transfer coefficient calculated by the correlations agreed with the experimental data from both two-phase and three-phase bubble columns

Lignocellulose was oxidatively decomposed in a newly developed polyoxometalates-imidazolium ionic liquid mixture. Aromatic compounds covering acids, esters, ketones, aldehydes, and phenols were selectively produced under various conditions. 4-Hydroxylbenzoic acid was dominatingly yielded under low temperature and high oxidant concentration. Phenolic compounds were mainly generated at high temperature with a selectivity of 45.1% and a yield of 4.3%, higher than those generated in similar polyoxometalates-ionic liquids system. The products distributions and residues of lignocellulose decomposition under various conditions were characterized; the influences of the ionic liquids anions on the polyoxometalates-ionic liquids complex formation, the acidic and redox properties of the catalyst, and the final products were profoundly investigated; and a tentative reacting process was proposed. The ionic liquid could be recycled for five times. This work not only provided a new lignocellulose decomposition strategy to produce aromatic products, but also offered a guidance for product-oriented lignocellulose decomposition.

As one of the significant part of IGFC (integrated gasification fuel cell) system, coal gasification technology has an important effect on system efficiency as well as technological process. To figure out what kind of gasifier technology could benefit IGFC system most, we select two representative gasifiers for comparison, which are E-Gas gasifier and Shell gasifier. In this study MW-level E-gas IGFC system and Shell IGFC system models are developed respectively, moreover, the energy analysis of two systems are carried out simultaneously. The results show that SOFC DC Power efficiency and system net plant efficiency of E-gas IGFC system are 52.82% and 50.89% , both higher than Shell IGFC system, which are 49.24% and 49.74%; under the same design conditions, gasifier with high content of CH 4 would be easier to obtain higher SOFC power efficiency as well as system net efficiency. The present work is helpful to provide gasifier selection suggestions for large-scale IGFC system.

Facile preparation of highly efficient iron-based catalysts is vital to improve the performance of Fischer-Tropsch synthesis (FTS), a sustainable process for converting non-petroleum carbon resources to valuable hydrocarbons. In this work, a convenient preparation for nitrogen-regulated graphene supported iron nanoparticles, with the assistant of microwave treatment, was developed. Thereinto, the nitrogen-containing groups in graphene support were introduced by NH3·H2O treatment. By comparison with ordinary calcination, microwave treatment could significantly shorten the heating time to few seconds, and promote the reduction of iron species. The existence of a small number of nitrogen-containing groups could effectively anchor iron species, and improve the dispersion of iron species. Meanwhile, the duration length of NH3·H2O treatment time could regulate the content of N configuration (pyridinic-N and pyrrolic-N). The size of supported iron species from 120 nm to 10 nm could be well controlled via increasing microwave time from 0 to 14 s. For N-regulated graphene supported iron catalysts, evenly dispersed small particles of iron species, improved surface reduction behavior and reasonable N configuration all promoted FTS. Under relevant industrial conditions (320 °C, 2.0 MPa, 5 g h mol−1), the optimized 15%Fe/AG(12 h)-W(10) catalyst achieved CO conversion as high as 97.2% and C5+ selectivity of 40.0% while maintaining a mild CO2 selectivity (28.2%). The superior preparation and catalytic performance disclosed that the catalyst could be one of ideal candidates for industrial iron-based FTS catalysts in future.

For Fe-based Fischer-Tropsch synthesis catalyst, how to decrease CO2 formation is a big challenge. In this work, a capsule catalyst (FeMn@HZSM-5) with FeMn as core and HZSM-5 as shell was prepared and used for Fischer-Tropsch to olefins (FTO) reaction, compared with bare FeMn catalyst and several hybrid catalysts by physically mixing FeMn and HZSM-5 in different ways. Among these catalysts, the FeMn@HZSM-5 capsule catalyst showed the best catalytic performance with the highest light olefins selectivity and the lowest CO2 selectivity. Compared with FeMn catalyst, the CO2 selectivity of FeMn@HZSM-5 catalyst decreased more than 10%. However, the CO2 selectivity of other physically mixing catalysts was similar to that of bare FeMn catalyst, indicating that randomly adding HZSM-5 had no effect on depressing the CO2 formation. Benefiting from the HZSM-5 shell, the FeMn@HZSM-5 capsule catalyst could effectively affect the diffusion of H2O and thus suppress the water-gas shift reaction in FTO reaction.

A gas-solid bi-phase mass flow rate measurement technology based on microwave transmission is presented to meet the demand of online flow measurement of pulverized coal in gasification plant. Unlike the methods based on capacitance senor, radiometric sensor and microwave reflection principle, the microwave mass flow meter transmitted microwave through the pulverized coal flow and received on the opposite by antennas. The energy of microwave was absorbed by coal particles. The attenuation degree of the microwave indicated the concentration of the pulverized coal flow. Comparative experiments of microwave mass flow meter and a commercial capacitance mass flow meter were conducted in pilot-scale gasification plant. Experimental results demonstrate the microwave mass flow meter has better dynamic performance than the capacitance mass flow meter in tracking transient fluctuations of pulverized coal flow, especially at start and stop sections during conveying procedure.