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Abstract: In this work, the denitrogenation of hydrocarbons under supercritical water oxidation environment was investigated in a rotated bomb reactor at 623–723K and 25–35MPa over sulfided NiMo catalyst. Quinoline was used as a model nitrogen-containing compound. A high reduction of total nitrogen up to about 85% was obtained. The denitrogenation pathway is composed of two consecutive steps: in situ H2 generation and the hydrogenation of quinoline. The hydrogenation mechanism of quinoline varies with reaction temperature because of the participation of supercritical water in HDN step. The strong adsorption of quinoline and its hydrogenation intermediates on catalyst surface has an adverse influence on total nitrogen reduction rate. [Copyright &y& Elsevier]

• The mesoporous iron oxide was successfully synthesized by using the waste wood powder as a template. • The alkali concentration had an effect on the physicochemical properties and performance of the synthesized iron oxides. • The iron oxide catalyst with larger surface area and pore volume exhibited higher yield of gasoline and diesel distillates. • The perfect performance of mesoporous iron oxide catalyst is ascribed to the presence of more exposure Fe active sites. In order to develop a high-efficiency iron oxide catalyst for the slurry-phase hydrocracking of poor heavy oil, the mesoporous iron oxide was successfully synthesized by using the waste wood powder as a template, and the influence of alkali concentration in the resulting solution on crystal phase, morphology and pore structure of the synthesized samples was investigated. The crystal phase of the synthesized iron oxide transfers from α-Fe 2 O 3 to γ-Fe 2 O 3 , and their crystal sizes gradually decrease with an increase of alkali concentration based on the XRD and HRTEM results. Additionally, the iron oxide with mesoporous structure, larger surface area and pore volume is obtained at the higher concentration of alkali in solution confirmed by N 2 adsorption-desorption analysis. The assessment result of the iron oxide catalyst employed in the slurry-phase hydrocracking of vacuum residue (VR) illustrates that the yields of gasoline and diesel distillates obtained over Fe-O-B 20 , Fe-O-B 24 and Fe-O-B 30 catalysts are higher compared with those over Fe-O-B 2 and Fe-O-B 14 catalysts, it can be attributed that more exposure Fe active sites derived from their larger surface area and pore volume availably improve the catalyst hydrogenation activity, which can inhibit the over-cracking reaction of intermediate products and the condensation of polycyclic aromatic hydrocarbon in VR to enhance the yields of gasoline and diesel distillates. [ABSTRACT FROM AUTHOR]

• ASA with the different Al/Si ratio were synthesized by a simple co-precipitation method. • The Al/Si ratio affects the Al coordination state, pore structure, acidity and surface properties of ASA. • Mo/ASA-4 with the largest amount of Mo atoms located at edge sites can provide the most amount of exposure Mo active sites. • Mo/ASA-4 catalyst achieves the highest yield of value light oil and the lowest yield of gas and coke due to its excellent hydrogenation activity. To deeply illuminate the effect of ASA composition on its corresponding Mo catalyst properties and performance for the slurry-phase hydrocracking of vacuum residue, the amorphous silica-alumina (ASA) samples with the various ratios of Al to Si were successfully synthesized by a simple co-precipitation method, which have the different acid properties and pore structure, especially ASA-1 with lowest ratio of Al to Si owning the largest number of B acid sites and the highest volume of mesoporous. Additionally, the Mo catalyst supported on ASA-4 possesses the highest dispersion of MoS 2 slabs and largest amount of Mo atoms located at the edge sites among all the catalyst, possibly due to the appropriate surface properties of ASA-4 derived from the ratio of Al to Si, it demonstrates that the most exposure Mo active sites are present on Mo/ASA-4 catalyst. The hydrocracking evaluation results show that the VR conversion over the different catalysts are similar, it may be ascribed to the variation of acid properties and pore structure insufficient to change VR cracking pathway because of the low catalyst dosage. Furthermore, the Mo/ASA-4 catalyst exhibits the higher yield of naphtha and middle distillate and inversely the lower yield of gas and coke in comparison with other catalysts, it should be attributed that the higher hydrogenation activity derived from the more exposure Mo active sites can efficiently restrain the over-cracking of the intermediate product and aggregation of the polycyclic aromatic hydrocarbon in the hydrocracking process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ball-milling process is used to prepare optimal NiP-Hβ/KL catalyst. • Modified Kaolin acts as a spacer to dilute the strong acidity of NiP-Hβ. • Mesopores in KL provides more activity sites for producing di-branched products. • NiP-Hβ/KL exhibits high conversion, high selectivity, and liquid yield. Isomerization of alkane is one of the most important catalytic processes for producing environmentally friendly gasoline fraction with high octane number. However, the development of non-noble metal based catalysts with high conversion and selectivity towards multi-branched isomerized products is still challenging. Herein, we report that a NiP-Hβ/modified Kaolin catalyst was successfully prepared by ball-milling of amorphous NiP nanoparticles with Hβ/modified Kaolin composites and applied for n-hexane isomerization. The introduction of chemically modified Kaolin with abundant weak-medium acid sites and mesopores not only alleviates the cracking of isomerized products on the strong acid sites on Hβ, but also provides more active sites for the formation of di-branched isomerized products with high octane number. As a result, the NiP-Hβ/modified Kaolin catalyst shows an excellent catalytic performance for n-hexane isomerization in terms of good conversion (78.1%), high selectivity towards mono-branched (75.4%) and di-branched (21.4%) i-C 6 products, and high liquid yield (99.9%). This work paves the way to the development of high performance non-noble metal based catalysts for large scale production of clean gasoline. [ABSTRACT FROM AUTHOR]