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Materials Data on NiMoP by Materials Project

NiMoP crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mo2+ is bonded to five P3- atoms to form distorted MoP5 square pyramids that share corners with ten equivalent MoP5 square pyramids, corners with six equivalent NiP4 tetrahedra, edges with six equivalent MoP5 square pyramids, and edges with six equivalent NiP4 tetrahedra. There are one shorter (2.42 Å) and four longer (2.57 Å) Mo–P bond lengths. Ni1+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with six equivalent MoP5 square pyramids, corners with ten equivalent NiP4 tetrahedra, edges with six equivalent MoP5 square pyramids, and edges with two equivalent NiP4 tetrahedra. There are two shorter (2.23 Å) and two longer (2.38 Å) Ni–P bond lengths. There are two inequivalent P3- sites. In the first P3- site, P3- is bonded in a 9-coordinate geometry to three equivalent Mo2+ and six equivalent Ni1+ atoms. In the second P3- site, P3- is bonded in a distorted trigonal planar geometry to six equivalent Mo2+ and three equivalent Ni1+ atoms.

36 MATERIALS SCIENCE↗

Kinetics of simultaneous hydrodesulfurization and hydrodenitrogenation reactions using CoMoP/Al 2 O 3 and NiMoP/Al 2 O 3

Hydrodesulfurization (HDS) is a key reaction to achieve diesel production at the specified low sulfur levels and is highly affected by a competing reaction involving nitrogen removal through hydrodenitrogenation (HDN). This work evaluated kinetic parameters of simultaneous reactions of HDS of dibenzothiophene (DBT) and HDN of quinoline (Q) using CoMoP/Al 2 O 3 and NiMoP/Al 2 O 3 catalysts under operational conditions that allow a wide range of reagent conversions. Estimated parameters were evaluated using rigorous statistical 2 analysis. Good fits for the evaluated experimental data were provided by both power-law and Langmuir-Hinshelwood models. Further, turnover frequency values highlight adsorption and competition effects between nitrogen-containing compounds and sulfur-containing compounds. NiMoP catalyst showed higher hydrogenating power than CoMoP, with larger absolute value of the estimated adsorption enthalpy (-120 kJ.mol -1 for NiMoP and -75 kJ.mol -1 for CoMoP), suggesting strong adsorption of nitrogen compounds. A catalyst with more hydrogenating power is also more capable of performing both HDN and HDS reactions simultaneously.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗