Hydrotreating reactions over supported Ni Mo S catalysts: investigations using model compounds

Abstract

the increasing demand for diesel fuels coupled with progressive newlinetightening of environmental specifications has brought new emphasis on newlineimproved hydrotreatment processes especially for gas oils hydrotreating newlineht is the most commonly used refinery process designed to improve the newlinequality of the feed or the product by decreasing the content of the undesired or newlineless desired components like s n o metals olefins and aromatics the main newlinereactions involved in hydrotreating ht are hydrodesulfurization hds newlinehydrodenitrogenation hdn hydrodemetallation hdm newlinehydrodeoxygenation hdo and hydrogenation hyd generally catalysts newlineused in hydrotreating reactions are mixed sulfides of c m nim or ni w newlinesupported on a high surface area carrier like al23 the use of other newlinesupports has also been reported in the literaturethe objective of the present work is to investigate the activity of sulfided ni m catalysts supported on different high surface area materials in individual ht reactions using model compounds nine different supports al2o3 al sba15 sba mcm 41 mcm almcm 41 almcm newline70 mcm 41 blended with alo mcm al and 70 almcm 41 newlineblended with aloalmcmal 15 and 30 bea supported on alo newline15bea al and 30bea al and 15 dealuminated bea alo newline15dalbeaal were loaded with nio 4 wt and mo 15 wt to newlineobtain different catalysts tpd temperature programmed desorption of nh was used to characterize the total acidity of the supports and catalysts oxide and sulfide newlineforms while cumene cracking at 623 673 k was used to characterize the newlinebrønsted acidity of the sulfide catalysts the xrd patterns of the catalysts newlineoxides reveal the absence of peaks due to the supported oxides nio m newlinein al but peaks attributable to nimo and mo are visible in the newlinepatterns of the catalysts prepared from the siliceous supports mcm 41 and newlinesba 15 the average pore diameters of the supports are in the mesopore newlinerange 2 2 to 8 3 nm newline newline newline