CoMo/Al2O3 catalysts prepared on the basis of Co2Mo10-heteropolyacid and cobalt citrate: Effect of Co/Mo ratio

Improvement of HDS catalysts through the modification of the oxidic precursor with 1,5-pentanediol: Gas phase sulfidation and thiophene conversion

“…Among them the use of Keggin or Anderson based heteropolyanions was proposed several years ago to prepare impregnating solutions instead of the classical ammonium heptamolybdate precursor [2,3]. Improvements have also been obtained through the addition of organic agents to the impregnating solution prepared with [4,5] or without [6] heteropolyanions. More recently the modification of dried or calcined oxidic precursors by organic molecules was shown to improve HDS catalytic performances [7e10].…”

“…In our laboratory TGA (thioglycolic acid) [7,8], also described as a sulfiding agent [15], was used to impregnate a commercial CoMo/Al 2 O 3 oxidic precursor. Recently due to its low cost and availability, citric acid has attracted much attention for the preparation of fresh catalysts [4,6,11]. Through the formation of Mo and/or Co complexes with the chelating agents, the improved HDS catalytic activities have been ascribed to (i) a decrease of the interaction between metals and the support [16e21] and/or to a lower formation of cobalt aluminate [2], (ii) an improvement of the Mo and/or Co dispersion [2,12,13,22e26], and (iii) the modification of the sulfidation of Co and Mo atoms (delay of Co sulfidation) [7,8,27e35].…”

Recovery of elemental sulphur via selective catalytic reduction of SO 2 over sulphided CoMo/γ-Al 2 O 3 catalysts

“…Co loading, Mo loading and the temperature for sulphurization were selected as the control parameters, which were previously found to have significant influence on the performance of desulphurization catalysts [17,18,23]. Table 1 shows the examined factors and selected levels of the catalysts.…”

Preparation and hydrodesulfurization properties of cobalt–molybdenum–phosphorous catalysts for removal of dibenzothiophene

“…However, the effect of Co/ Mo on the physicochemical property was not studied. Nikulshin et al [8] also investigated the effect of Co/Mo ratio and found out that catalysts with Co/ (Co ? Mo) = 0.35 had maximal activities in 4,6-DMDBT HDS.…”