Effects of phosphorus and saccharide on size, shape, and reducibility of Fischer–Tropsch catalysts for slurry phase and fixed-bed reactions

Phosphorus‐Modified Mesoporous Inorganic Materials for Production of Hydrocarbon Fuels and Value‐Added Chemicals

“…[38,43,50] The conversion of CO was higher on the Co/PÀ Al 2 O 3 in a fixed-bed reactor, which has relatively lower degree of Co reduction, as compared to the CSTR, though Co dispersion seems to be more associated with C 5 + productivity than the degree of reduction. [38,50] In general, as shown in Table 2, the Co-supported on P-modified alumina (Co/PÀ Al 2 O 3 ) catalyst displays a better catalytic activity, stability and C 5 + selectivity, which were mainly attributed to the combined effects of enhanced dispersion with good reducibility of Co species, the formation of a homogeneously distributed smaller Co clusters and less deposition of heavy hydrocarbons by forming the macro-emulsion droplets during FTS reaction compared to the results obtained from P-unmodified alumina catalyst (Co/Al 2 O 3 ). Moreover, PÀ Al 2 O 3 greatly suppressed the migration of Co nanoparticles to the outer pore mouths of the support due to the localized presence of AlPO 4 by forming a thermally stable metal-phosphorus oxo-species on the outer Al 2 O 3 surface.…”

“…[34,36,37] Due to the higher prices of those precious metal promoters, the design of highly active and stable Co-based FTS catalysts on either Al 2 O 3 or SiO 2 have been broadly investigated with inexpensive phosphorus species as structural promoters. [11,[38][39][40] In the following section, the effects of phosphorus promoter on the Al 2 O 3 and SiO 2 supports for Cobased FTS catalysts have been discussed briefly.…”

“…It also alters the surface hydrophilicity and dispersion of the supported Co crystallites. The Co/PÀ Al 2 O 3 catalysts have used in both fixed-bed reactor [38,45,47,[49][50][51][52][53][54][55] and slurry-phase continuous stirred-tank reactor (CSTR). [38,43,50] The conversion of CO was higher on the Co/PÀ Al 2 O 3 in a fixed-bed reactor, which has relatively lower degree of Co reduction, as compared to the CSTR, though Co dispersion seems to be more associated with C 5 + productivity than the degree of reduction.…”

“…The Co/PÀ Al 2 O 3 catalysts have used in both fixed-bed reactor [38,45,47,[49][50][51][52][53][54][55] and slurry-phase continuous stirred-tank reactor (CSTR). [38,43,50] The conversion of CO was higher on the Co/PÀ Al 2 O 3 in a fixed-bed reactor, which has relatively lower degree of Co reduction, as compared to the CSTR, though Co dispersion seems to be more associated with C 5 + productivity than the degree of reduction. [38,50] In general, as shown in Table 2, the Co-supported on P-modified alumina (Co/PÀ Al 2 O 3 ) catalyst displays a better catalytic activity, stability and C 5 + selectivity, which were mainly attributed to the combined effects of enhanced dispersion with good reducibility of Co species, the formation of a homogeneously distributed smaller Co clusters and less deposition of heavy hydrocarbons by forming the macro-emulsion droplets during FTS reaction compared to the results obtained from P-unmodified alumina catalyst (Co/Al 2 O 3 ).…”

Effect of the Support and Its Surface Modifications in Cobalt-Based Fischer–Tropsch Synthesis

“…91%). Two-dimensional (2D) elemental maps deduced by 2D energy-filtered TEM and 59 Co NMR analysis revealed that the nanoscale introduction of TiO 2 into the β-SiC matrix significantly enhanced the formation of small and medium-sized cobalt particles. Furthermore, the proper metal−support interaction between cobalt nanoparticles and TiO 2 led to the formation of smaller cobalt particles (<15 nm), resulting in a large fraction of surface atoms and, consequently, a great enhancement of the catalytic activity.…”