Papers by Author: R.R. Silva

Abstract: The present work, the HPA Keggin structure was supported on four different MCM phase types (hexagonal, spherical, elliptical, and cubic); their catalytic properties were tested in the alkylation of benzene with propylene in order to produce cumene. In the reaction, parameters like propylene flow, reaction temperature, phase type, as well as WHSV-1, HPA, and Cs content in the best MCM phase support were studied. The results showed that the MCM-48 with (30 wt. % HPA) catalyst had the best behavior in catalytic activity, showing the higher conversion and selectivity toward cumene as the main product.

Abstract: In this paper, the incorporation of carbide and nitride phases supported on mesoporous materials like SBA type is described in order to obtain a better material than commercial catalysts (NiMoS/Al2O3, Sg=269 m2.gr-1) specifically in the HDS of dibenzothiophene. The XRD patterns exhibit the presence of carbide and nitride phases in each series, respectively. In the nitride materials, the presence of oxide phases was more evident than in the carbide catalysts. The principal product was biphenyl (BF) for all the analyzed series. This behavior suggests that the DBT desulphurization pathway for the carbide materials was similar to that of sulfide catalysts. Bicyclohexyl (BCH) was analyzed as a product, and cyclohexylbenzene traces (CHB) were determined in a single catalyst (NiMoC-2%P/SBA-16). This was attributed to the hydrogenation character of carbide catalyst reported previously.