Effect of Manganese Promotion on Al-Pillared Montmorillonite Supported Cobalt Nanoparticles for Fischer-Tropsch Synthesis

Abstract

The effect of Mn-promotion on high surface area Al-pillared montmorillonite (AlMMT) supported Co nanoparticles prepared by hydrothermal method have been investigated. A series of different weight% Mnpromoted Co nanoparticles were prepared and characterized by XRD, TPR, TGA, BET and SEM techniques. An increase in the surface area of MMT is observed with Al-pillaring. Fischer-Tropsch catalytic activity of the as prepared catalysts was studied in a fixed bed micro reactor at 225 o C, H 2 /CO = 2 and at 1 atm pressure. The data showed that by the addition of Mn the selectivity of C 1 dropped drastically while that of C 2 -C 12 hydrocarbons increased significantly over all the Mn-promoted Co/AlMMT catalysts. The C 13 -C 20 hydrocarbons remained almost same for all the catalysts while the selectivity of C 21+ long chain hydrocarbons decreased considerably with the addition of Mn. The catalyst with 3.5%Mn showed lowest C 21+ and highest C 2 -C 12 hydrocarbons selectivity due to cracking of long chain hydrocarbons over acidic sites of MMT.

Morphology, Dielectric and EMI Shielding Characteristics of Graphene Nanoplatelets, Montmorillonite Nanoclay and Titanium Dioxide Nanoparticles Reinforced Polyvinylidenefluoride Nanocomposites

“…The XRD pattern of MMT nanoclay also displayed several prominent diffraction peaks associated with its lamellar structure. The diffraction peak at 2θ = 12.52° is attributed to (001) reflection while the peaks at 2θ = 20.62° (100) and 2θ = 35.08° (110) are associated with pyrophyllite mineral phase of MMT [57,58]. The XRD patterns of PVDF/GNPs/MMT/TiO 2 and PVDF/ GNPs/TiO 2 nanocomposite films are depicted in Fig.…”

Recent Advances in Bifunctional Catalysts for the Fischer–Tropsch Process: One-Stage Production of Liquid Hydrocarbons from Syngas

“…The evaluation of Co load on a support of Zr-pillared MMT showed that higher activity (CO conversion) was obtained when 20 wt % (nominal load) Co was used, with conversion of 53% and high selectivity to C 2 −C 12 products (∼45%); this was explained to be resulting from increased Co reducibility and hydrocracking occurring in the sites of the pillared clay. 161 The effect of promoter loading in the FT process has also been evaluated. For example, Ahmad et al 161 showed that loading of 1.5 wt % Mn to a Co catalyst supported on Al-pillared MMT promoted an increase of 45% in CO conversion, a decrease in methane selectivity (from 27 to 14%), and an increase in the selectivity of C 2 −C 12 products (from 18% to 44%) in comparison with the nonpromoted catalyst.…”

“…161 The effect of promoter loading in the FT process has also been evaluated. For example, Ahmad et al 161 showed that loading of 1.5 wt % Mn to a Co catalyst supported on Al-pillared MMT promoted an increase of 45% in CO conversion, a decrease in methane selectivity (from 27 to 14%), and an increase in the selectivity of C 2 −C 12 products (from 18% to 44%) in comparison with the nonpromoted catalyst. The presence of Mn was found to enhance the reducibility of Co and the acidity of the pillared clay.…”

“…The performance of bifunctional Co catalysts supported on pillared MMT was evaluated, showing promising results. The evaluation of Co load on a support of Zr-pillared MMT showed that higher activity (CO conversion) was obtained when 20 wt % (nominal load) Co was used, with conversion of 53% and high selectivity to C 2 –C 12 products (∼45%); this was explained to be resulting from increased Co reducibility and hydrocracking occurring in the sites of the pillared clay . The effect of promoter loading in the FT process has also been evaluated.…”