Interaction between Weibull parameters and mechanical strength reliability of industrial-scale water gas shift catalysts

Effect of Secondary Additives on the Properties of Vanadium-Aluminum Mixed Oxide Catalysts Used in the Oxidation of Propane

“…As already mentioned, besides reactivity, technical catalysts are also assessed in terms of their mechanical strength. 2,9,10,22,[28][29][30] Recalling our results on this property, Figures 1 and 3 and Table S1, the eventual use of tablets formulated with sepiolite and boron nitride in a fixed-bed unit would be a good trade-off between reactivity and mechanical resistance because the latter was higher as compared to the mechanical resistance of the tablets made with the powder of the vanadiumaluminum mixed oxide. Furthermore, as we reported earlier 34 the continuous production of VAlO tablets was impracticable hence the use of graphite or of another type of lubricant is mandatory.…”

“…3,12,19 When a technical catalyst is installed within these reactors, its lifespan depends on how it withstands the chemical, thermal, and mechanical stresses imposed by their own weight, the weight of the reactants, and the constantly changing operation conditions of the process. [20][21][22][23][24][25][26][27][28][29][30] The effects of these stresses are intricately interconnected with each other; e.g. thermal stresses may lead to sintering or crystallization that may make the technical catalyst brittle henceforth promoting particle breakage into irregular bodies and fines that cause channeling, hot-spots, and increased pressure gradients to a point where the reactor plugs and the operation must be stopped.…”

CuFeAl Nanocomposite Catalysts for Coal Combustion in Fluidized Bed

“…Antonyuk et al [32] obtained the Weibull modulus m 5 for spherical -Al2O3 granules. For a series of water gas shift catalysts based on alumina, M. Zakeri et al [29] observed values of m in the range of 2.5-11. As seen from Figure 3, an increase in the pseudoboehmite content leads to an increase in the strength of the obtained catalyst granules and to a simultaneous decrease in the activity of the catalyst.…”

“…At a pseudoboehmite content of ≥40%, the obtained granules of the spherical CuFeAl nanocomposite catalyst have a high mechanical fracture stress, exceeding an average of 15 MPa. However, it is necessary to take into account the variance of this value [28][29][30]. This is important because porous materials contain defects that are randomly distributed over the volume.…”

“…Antonyuk et al [32] obtained the Weibull modulus m ≈ 5 for spherical γ-Al 2 O 3 granules. For a series of water gas shift catalysts based on alumina, M. Zakeri et al [29] observed values of m in the range of 2.5-11. Based on the obtained Gamma distribution parameters, the fraction of granules with the fracture stress less than 7 MPa was estimated ( Table 3).…”