Dynamics of adsorption by zeolites from the liquid phase, simulated using data on adsorption statics

A mathematical model for calculation of the dynamics of liquid-phase adsorption in a fixed sorbent bed is constructed on the basis of material balance equations solved by numerical integration on the assumption of a constant mass-transfer coefficient and a limiting inner-diffusion resistance.     

The heat of dissolution of uranyl nitrate in aqueous nitrate solutions

Conclusions A model has been suggested to explain the observed relationship between the measured heats of dissolution of uranyl nitrate in aqueous nitrate solutions and the concentration of the salting-out agent. The model describes the change in the structure of water in the solution with change in its concentration. On the one hand, a destruction of the water structure by ions occurs, which is weakened with increase in the distance from the ion, and leads to such irregularity in the distribution of water molecules in the solution that the mean number of molecules of water in unit volume is increased with increase in the distance from the ions. In experiments on the heat of dissolution this increase leads to increased hydration of the uranyl cation and reduction in the endothermicity of the dissolution with increase in the concentration of the solution. On the other hand, an interaction occurs between the ions of the salting-out agent and the water molecules in the solution, leading to the opposite result: There is an increase in the mean number of water molecules of the solution in unit volume in the direction of these ions. In experiments on the heat of dissolution this is revealed in the dehydration of the uranyl cation, and correspondingly in an increase in the endothermicity of the dissolution with increase in the concentration of the solution. The proposed model is in harmony with data on vapor pressure above the solutions (the relationship between the activity coefficient of the water and the concentration of the solution).Translated from Zhurnal Strukturnoi Khimii. Vol. 3, No. 2, pp. 143–150, March–April. 1962     

Noncatalytic hydrophosphorylation and hydrothiophosphorylation of hydroxyaldehydes

Nucleophilic addition of secondary phosphone oxides and phosphine sulfides to 2-hydroxyacet-, 2-hydroxybenz-, and 3,4-dihydroxybenzaldehydes proceeds under mild conditions (48–50°C, THF) and allows tertiary phosphine oxides and phosphine sulfides with several hydroxyl groups to be prepared.     

Synthesis and electrocatalytic activity of palladium nanoparticles on porous silicon

Palladium was combined with porous silicon into catalytically active functional electrode nanocomposites. Palladium nanoparticles were examined by transmission electron microscopy and atomic force microscopy; their catalytic activity was estimated using cyclic voltammetry.     

Development of Ni–Mo Sorption-Catalytic Materials for Removing Arsenic Compounds from Middle Distillates

Possibility of using mesoporous materials for obtaining Ni–Mo sorption-catalytic materials for purification of medium-distillate fractions to remove arsenic-containing compounds was examined. It was shown that, in the course of hydropurification, the acidity of the mesoporous material does not directly affect the extent to which the amount of arsenic in hydrocarbons is diminished. It was found that mesoporous supports of the SBA-15, TUD, and MCF types reduce the content of arsenic to less than 0.5 ppm at 360°C and 50 atm of H₂.