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The presence of Na in Ni-promoted MoS 2 provides an interesting case study as Na gets inadvertently incorporated during the reverse micelle synthesis of the nanocatalyst. The effect of Na in Ni-promoted MoS 2 during hydrodesulfurization (HDS) of dibenzothiophene (DBT) is investigated here through combined experiment and density functional theory (DFT) studies. Computations suggest that Na replaces otherwise more HDS active Ni sites, which are likely to be present as metal atoms on S edge or on metallic edge sites of MoS 2 (100). The presence of Na dopant instead of Ni results in the molecular hydrogen dissociation step becoming more endothermic, leading to the lowering of HDS catalytic activity. The HDS of DBT decreases with an increase of Na concentration in Ni-promoted MoS 2 . However, the concentration of Na has a nonmonotonic effect on the selectivity of different mechanistic pathways of HDS. The selectivity toward a cost-effective direct desulfurization (DDS) pathway increases up to an optimal Na concentration, after which the selectivity decreases as observed from experiments and corroborated by DFT studies. However, DDS selectivity always remains higher, which is the critical feature of Na incorporation in Ni-promoted MoS 2 .

Monoclinic [LiAl2(OH)6]OH·2H2O was formed by the hydrolysis of LiAlH4 within few minutes of irradiation with microwaves as confirmed by powder X‐ray diffraction (PXRD), infrared, Raman, 27Al NMR spectroscopic, and thermal analysis experiments. The flaky morphology of crystallites was evident in microscopy images. The compound is mesoporous with surface area of 50 m2/g. When required amounts of corresponding mineral acids were added during the hydrolysis of LiAlH4, exchange of the interlayer hydroxide ion with nitrate and chloride ions was successful. This was verified by the hexagonal symmetry observed in the PXRD patterns together with the evidence gathered from infrared, 27Al NMR spectra, thermal analyses, and the substantial changes in ligand to metal charge‐transfer bands in their UV/Visible spectra. A host of Li‐Al LDH compounds intercalated with aliphatic dicarboxylate (oxalic, malonic, succinic, glutaric, adipic, and sebacic acid) anions were rapidly produced when a mixture of LiAlH4 and the respective acid was irradiated with microwaves for a few minutes. The basal spacing of the dicarboxylate anion intercalated systems increased linearly with the increase in the number of –CH2‐ groups in them. Microwave assisted reaction of ethylene glycol with [LiAl2(OH)6]OH·2H2O resulted in its intercalation.

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