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The development of new improved catalysts for the selective hydrogenation of aromatic nitrogroups is still a field of high interest for the chemical industry. Hydrogenation of aromatic nitrogroups to the corresponding aromatic amines is one of the most important applications for precious metal powder catalysts (PMPC). In this paper various commercial PMPC technologies such as palladium, platinum, platinum modified with copper and platinum modified with vanadium on activated carbon powder supports were compared to each other in regard to activity and selectivity for hydrogenation of 1-chloro-2-nitrobenzene. In this reaction, catalysts comprised of vanadium modified platinum on activated carbon showed excellent activities and selectivities towards 2-chloroaniline. Catalyst performance was affected by the ratio of platinum to vanadium and the properties of the carbon. The role of vanadium as an effective modifier to avoid accumulation of hazardous aromatic hydroxylamines was explained.

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In this manuscript, an in situ layered intumescent flame retardant (IFR) of graphene oxide (GO) was used to produce a polybutylene terephthalate (PBT) flame‐retardant material with different flame‐retardant concentration gradients. IFR was introduced into the GO layered structure via a chemical reaction to achieve an in situ flame‐retardant effect. The elements of the composite were characterized using energy dispersive spectroscopy. The results showed that although the subsequent PBT‐based flame‐retardant composites displayed low flame‐retardant content, it exhibited excellent flame retardancy and mechanical properties. Due to the introduction of GO, the flame retardancy of the composites was improved significantly. The lamellar structure of GO provided a barrier allowing it to absorb condensed nucleus compounds. Therefore, continuous and compact scaly carbon layers were formed in the matrix during the burning process.