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Composite pelletized catalysts for higher one-pass conversion and productivity in the Fischer–Tropsch process are reported. The introduction of aluminum metal powder as a thermal conductor leads to the formation of a new family of composite pelletized catalysts, very different from reference systems. In particular, these catalysts retain high activity and C5+ selectivity at increasing gas-hour space velocities of up to 5,000 h−1. The productivity of these composite catalysts increases almost fourfold for fivefold GHSV increase. Composite catalysts with different types of active cobalt (conventional, introduced by impregnation, or skeletal) show similar values of one-pass conversion and productivity but give different fractional and group composition of liquid hydrocarbon products. Testing of these highly productive catalysts in reactors with different aspect ratios showed that high productivity and one-pass conversion can be achieved in industrial-size units, where feasible liquid yield of up to 140 barrels per million standard cubic feet (MMSCF) of natural gas can be reached.

The formation of surface cobalt structures was investigated for a number of β-SiC-supported Fischer–Tropsch catalysts. Several different supports were used, both pristine and alumina-modified β-SiC. The techniques of temperature-programmed reduction, nitrogen physisorption, thermal gravimetric analysis, heat conductivity and catalytic testing in Fischer–Tropsch synthesis were employed. It was determined that despite highly similar manufacturer specifications, differences in support genesis may lead to different porosities, surface cobalt phase compositions and catalytic activity, even with the use of identical catalyst preparation procedures. The control of the formation of the surface cobalt structure can also be realized by parameters of the catalyst preparation, such as one- or multi-step impregnation from aqueous or ethanol solution and annealing in air or helium flow or without gas flow. These findings open avenues of research for the optimization of the whole catalyst formation route on the basis of identification of the most efficient surface cobalt phase composition and realization of higher thermal conductivity.

A mathematical model of heat and mass transfer processes in the grain of the Fischer-Tropsch synthesis catalyst is presented that takes into account the effect of the capillary condensation of the products of the synthesis in the pores of the catalyst. The influence of capillary condensation on the processes of the diffusion transfer of heat and mass in the catalyst grain is analyzed using the proposed model. Dependences of the efficiency factor of the grain on the pressure and temperature of the process and the partial pressure of various components of a mixture are presented. The possibility of determining the optimum pressure and temperature of carrying out the process for the catalyst of a certain structure is shown.

The decomposition of methane on catalysts prepared by metal deposition on carbon fiber was investigated. It was found that new carbon deposits having a threadlike form and a nanotube structure are formed on nickel-containing samples.

The formation of heterogeneous mercury-, zinc-, and copper-containing catalytic systems obtained by supporting salt components (SCs) without a solvent is studied. It is shown that due to strong interaction between SC and support, the size of salt clusters on the surface and their relative contribution decrease. That is, the concentration of excess salt phases decreases. The dispersity increases up to molecular distribution. When surface-linked two-dimensional disordered structures are formed, the state of salt phases in the compositions of catalytic systems changes. The surface mobility of salt clusters during the contact with the reaction medium is found. Compared to the systems obtained by impregnation with aqueous solutions, the proposed systems are 2-3 times more thermally stable, their surface is enriched in defect structures that are active in catalysis, and the processes of organochlorine synthesis become more efficient.

1. It has been shown by means of x-ray phase analysis that in supported copper chloride catalysts for the oxidative chlorination of hydrocarbons, the salt component interacts with the support (metastable aluminum oxides or an amorphous aluminosilicate), this interaction leading to the formation of a complex multiphase system. 2. The structure of the support influences the crystallization of the excess salt component, resulting in oriented growth of the crystals. 3. On an aluminosilicate support, copper hydroxochlorides are formed selectively, so that they constitute a large part of the supported salt component.

1. In copper-containing salt catalysts for oxidative chlorination on various carriers, catalysts with the same amount of applied salt component have a different surface composition as a result of the reaction with the carrier. The formation of surface melts is a function of the nature of the carrier and the concentration of the salt component. 2. “Separation” of the KCl·CuCl2 salt system with formation of surface states characteristic of KCl/carrier and CuCl2/carrier systems takes place on carriers with a developed surface. 3. Elimination of water molecules and hydroxyl groups from the surface of the carrier is significantly facilitated under the effect of the salt component. 4. Due to the reaction with the carrier, the salt component in the catalyst decomposes more easily than the individual salt system.

1. By means of electron microscopy and an investigation of adsorption, involving x-ray diffraction and DTA, the observed morphological structures have been characterized in the catalytic systems copper(II) chloride-α-aluminum oxide and copper (II) chloride-potassium chloride-α-aluminum oxide, 2. When the catalytic, systems are heat-treated, the salt clusters acquire mobility as a consequence of the formation of fusible compositions or surface migration of salt phases in a premelting state. When this occurs, changes are observed in the structure and surface area of the salt clusters.

1. Copper chloride catalysts for oxidative chlorination of hydrocarbons are multicomponent heterogeneous systems which consist of both melts of varying composition and of coexisting solid phases formed during thermolysis of the salt component. 2. In copper-containing salt catalytic systems, the active component reacts with the carrier with the formation of new phases. 3. In thermolysis of these systems, the Headwall effect is observed, which permits identifying the phase transitions and transitions of the “order-disorder” type in the crystal lattices when the system is heated by the method of differential thermogravimetric analysis.

1. In catalysts containing copper salts on aluminum oxide support, various structures containing copper have been found that form by the reaction of the salt with the support surface. 2. The kind of structure that forms depends on the phase composition and the acid-base properties of the support surface. 3. Surface structures can affect the coalescence of catalyst particles under reaction conditions, and thus change the hydrodynamics of a fluidized bed.