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Slurry-phase hydrocracking (SPHC) of unconventional heavy feedstocks is considered as a promising process to fill the gap between the ever-increasing demand for vehicle fuels and the fast-depleting supply of conventional crude oil. The one-through nature of SPHC processes requires low-cost yet high-performance catalyst. This article reports a simple but effective hydrothermal modification strategy to treat a cheap natural bauxite mineral as a support (HMB) to prepare SPHC catalyst (HMBC) with outstanding catalytic performance. For comparison, an acid-modified bauxite (AMB) derived catalyst (AMBC) was also prepared. The physicochemical properties of HMB, HMBC, AMB and AMBC were systematically characterized, and the catalytic performance of HMBC and AMBC was assessed in the SPHC of a high temperature coal tar (HTCT). The results showed that HMBC exhibited HTCT hydrocracking activity superior to AMBC, attributed to the more suitable acidity of the support HMB and the weaker interaction between MoO 3 and HMB that results in the higher sulfidation degree of molybdenum oxide species and thereby provides more active MoS 2 phases for hydrocracking. Furthermore, compared with the acid treatment previously reported, the hydrothermal modification is simpler, more energy-saving, and more environment-friendly and therefore is feasible for industrial application.

The hydrothermal synthesis of zeolite from chemical Al/Si source in the presence of structure directing agent is considered to be a resource extensive, energy consuming, and environmental unfriendly process. Herein, we report a novel, cost-effective, and eco-friendly synthesis for the preparation of ZSM-5 zeolite from silicon-rich diatomite and aluminum-rich rectorite minerals in the absence of organic structure-directing agent and chemical Al/Si source. Synthesis factors (SiO2/Al2O3, Na2O/SiO2, and H2O/SiO2 molar ratios along with seed content) and crystallization behavior were systematically investigated, providing fundamental knowledges on the formation of ZSM-5 from natural minerals. Synthesis under the optimized conditions (SiO2/Al2O3 ratio of around 38, Na2O/SiO2 ratios of 0.12–0.15, H2O/SiO2 ratios of 15–25, and seed content above 0.5%) led to production of highly crystalline ZSM-5 zeolite with hexagonal prism morphology and large surface area. Various characterization techniques tracking the products at different crystallization times revealed that the crystallization process consisted of three stages: short induction stage (0–6 h), rapid growth stage (6–18 h), and stable growth stage (18–36 h). Moreover, the synthesized ZSM-5 crystals can be used as effective seed for producing the next generation of ZSM-5 zeolite.

The use of natural aluminosilicate minerals as the low-cost starting materials for zeolite synthesis is a field of current interest. However, impurities existing in these minerals greatly affect the purity of final products. Herein, we describe a cheap and green route for synthesizing pure-phase zeolite beta from natural aluminosilicate minerals via a modified nanoscale depolymerization-reorganization approach. The physicochemical and catalytic properties of the synthesized zeolite beta were systematically characterized and assessed, respectively. The results indicate that the resulting zeolite beta possesses more moderate Bronsted acid sites compared with the reference one, and thus exhibits higher catalytic activity in the esterification of acetic acid with ethanol. This methodology demonstrates great perspective for the low-cost and environmentally-benign synthesis of zeolite beta that avoids the use of aluminum- and silicon-containing inorganic chemicals, eliminates the interference of impurities, and reduces the usage of the organic template.

Heterobimetallic zeolites have been considered as highly efficient catalysts to reduce nitrogen oxide emissions, but economic and sustainable preparation methods have been lacking. This paper presents an economic and sustainable one-pot synthesis strategy to prepare the heterobimetallic FeCu-SSZ-13 zeolite (FeCu-SSZ-13M) with high crystallinity via the mesoscale depolymerization-reorganization of natural aluminosilicate minerals without the use of any synthetic silicon-, aluminum-, and iron-containing chemicals. Systematic characterization results reveal that the resultant FeCu-SSZ-13M sample has smaller crystallize size, larger specific surface area and pore volume (especially external specific surface area and mesopore volume), lower acid strength and more isolated Cu2+ and framework Fe3+ ions when compared with Cu-SSZ-13C and FeCu-SSZ-13C prepared from conventional precursors. Therefore, it exhibits outstanding catalytic performance (such as super-wide reaction temperature window, excellent hydrothermal stability, high H2O and SO2 tolerance, and good gaseous hourly space velocity flexibility) in the selective catalytic reduction of NO by NH3. Our research contributes to the design and synthesis of an efficient environmental protection catalyst in an economic and sustainable manner.

Synthesis of zeolites from natural aluminosilicate minerals is a green and sustainable technology. One major challenge in the synthesis is how to enhance the reactivity of the natural minerals. Herein we developed a facile quasi-solid-phase method to efficiently depolymerize natural rectorite into its corresponding mesoscale building blocks, i.e., TO4 (T = Si or Al) monomers or oligomeric species. Natural rectorite can be completely and efficiently depolymerized at 170 °C within 60 min, which is substantially lower than temperatures (>900 °C) used in industrial depolymerization methods. The transformation of Si and Al species in the QSP depolymerization mainly undergoes three stages: (1) the layer of Na6AlVI4AlIV2Si6O24·nH2O is dissociated and converted into Na6AlVI2AlIV4Si6O24; (2) Na6AlVI2AlIV4Si6O24 is further depolymerized into Na4AlIV4Si6O20 and monomer NaAlIVO2; (3) Na4AlIV4Si6O20 is finally decomposed into mesoscale monomers (Na4SiO4 and NaAlIVO2), dimers (Na6Si2O7), and chains (Na2SiO3). Moreover, the depolymerized rectorites exhibits high reactivity for synthesizing highly crystalline ZSM-5 zeolite.

A template free synthesis route was developed for the synthesis of hierarchical zeolite Beta from a natural layered aluminosilicate mineral kaolin. Detailed study on the crystallization of zeolite Beta established the optimized synthesis condition, and the synthesized hierarchical Beta zeolite was fully studied by XRD, IR, SEM, TEM, BET, NH3-TPD, Py-IR and NMR techniques. The characterization results reveal that the hierarchical Beta zeolite possesses good crystallinity, bimodal pore architecture, large surface area, big pore volume, high acid site concentration and excellent hydrothermal stability. An improved catalytic performance was achieved in hierarchical Beta zeolite for the esterification of acetic acid with benzyl alcohol, and the high activity and selectivity in this zeolite are mainly attributed to the presence of mesopores for accelerating the intraparticle diffusion rate of both reactant and product. This novel synthesis methodology provides a low-cost and environmentally-benign way for the preparation of hierarchical Beta zeolite, which could serve a sustainable platform of large-scale production of hierarchical zeolite for practical application.

The syntheses and structures of two ethyl mercaptan molecular wheels complexes, [M(μ2-SCH2CH3)2]6 (M=Fe, Co), have been reported. Each metal atom is surrounded by four S atoms of the μ2-SCH2CH3 ligands in a distorted square plane fashion. The edge-sharing S4 square planes connect with each other to form a ring. Six metal atoms are located at the vertices of an almost hexagon, with M···M separations in the range of 2.903(1)~2.936(2) A for Fe and 2.889(2)~2.962(2) A for Co. The diameter of the ring, defined as the average distance between two opposing metal atoms, is 5.850(1) A for Fe and 5.780(1) A for Co, respectively. The magnetic property behaves of cobalt(II) cluster complex is studied.

The nucleophilic trifluoromethylthiolation of benzyl bromides using (bpy)Cu(SCF3) gave the desired products of benzyl trifluoromethyl sulfides in good to excellent yields. A diverse set of important functional groups including cyano, nitro, ester, alkoxy, halide, and heterocyclic groups can be well tolerated in the protocol.

The direct palladium-catalyzed coupling of polyfluoroarenes with aryltrifluoroborates gave the desired products of fluorinated biaryls in good to excellent yields. A diverse set of important functional groups including methoxy, aldehyde, ester, nitro and halide can be well tolerated in the protocol.