Influence of Amino Acids and Alcohols on Catalytic Oxidation of Cyclohexane

Conducted experiments and collected data show that use of catalytic systems that contain individual amino acids and industrial catalyst – solution of cobalt naphtenate with cyclohexanone – have certain influence on the process of liquid-phase homogeneous oxidation of cyclohexane. The results of spectral studies of binary catalytic systems based on NC using additives of different nature (alcohols and nitrogen-containing modifiers) allow us to propose structural formulas of catalytic complexes.

Diffusion and catalyst efficiency in hierarchical zeolite catalysts

The preparation of hierarchical zeolites with reduced diffusion limitation and enhanced catalyst efficiency has become a vital focus in the field of zeolites and porous materials chemistry within the past decades. This review will focus on the diffusion and catalyst efficiency of hierarchical zeolites and industrial catalysts. The benefits of diffusion and catalyst efficiency at two levels of hierarchies (zeolitic component level and industrial catalyst level) from a chemical reaction engineering point of view will be analysed. At zeolitic component level, three types of mesopores based on the strategies applied toward enhancing the catalyst effectiveness factor are presented: (i) ‘functional mesopores’ (raising effective diffusivity); (ii) ‘auxiliary mesopores’ (decreasing diffusion length); and (iii) ‘integrated mesopores’ (a combination thereof). At industrial catalyst level, location and interconnectivity among the constitutive components are revealed. The hierarchical pore interconnectivity in multi-component zeolite based industrial catalysts is exemplified by fluid catalytic cracking and bi-functional hydroisomerization catalysts. The rational design of industrial zeolite catalysts at both hierarchical zeolitic component and catalyst body levels can be fully comprehended using the advanced in situ and/or operando spectroscopic, microscopic and diffraction techniques.

Characterization of the spent industrial catalyst Co-Mo/Al2O3 for fine hydrotreatment of diesel fuel

Physicochemical properties of the spent industrial catalyst Co-Mo/Al2O3 for hydrotreatment of diesel fuel were studied. IR, TG, DTA and SEM techniques were used to establish that the catalyst surface is covered uniformly by a coke film; the soft coke consists predominantly of a mixture of slightly branched saturated hydrocarbons. Coke is oxidized at 190–375 °C (soft coke) and 375–525 °C (hard coke) and was removed quantitatively by calcining in air at 550 °C for 3 hours. XRD and SEM techniques, low temperature nitrogen adsorption, and chemical analysis were used to demonstrate considerable changes in the structure of the spent catalyst (phases Co3O4, CoCO3 and CoSO4·6H2O); the Mo content decreased by 7.7 %; Fe, Na and V impurities were accumulated; sintering resulted in a decrease in the specific surface area and total pore volume by 31.5 and 28.4 %, respectively. The data obtained are necessary for developing methods for the catalyst utilization.