Deironing of Underground Water with Modified Refractory Chamotte

Water from underground sources in Russia and the CIS countries mainly contains higher concentrations of iron and manganese. With a permissible rate of iron content in drinking water of 0.2–0.3 mg/L, its content in groundwater can reach 40 mg/L. To remove excess soluble iron, it is oxidized to insoluble forms. For these purposes, iron removal filters are used. This research describes the preparation of modified catalytic material to intensify the process of deferrization of underground water. Methods. Refractory chamotte of a fraction of 3–5 mm was selected as the base material, and an iron-containing precipitate of the purification of washings waters from iron removal filters was used as the source of iron for the preparation of the precursor solution. As a result of the modification, the formation of a finely dispersed and crystalline structure of hematite on the chamotte surface occurred. The effect of the dose of iron nitrate on the iron content on the surface of the modified material is established. Results. During pilot tests, it was found that an increase in the concentration of iron on the surface from 5.8 wt.% in the initial chamotte to 19.0, 48.7 and 55.8 wt.% in the modified led to an increase in the degree of iron oxidation from Fe2+ to Fe3+ from 41.4% to 65.1, 73.0 and 80.0%, respectively. The proposed method has significant advantages over analogues due to significantly lower energy consumption, resource consumption and impac on environmentt.

Graphical Approach to Compare Concentration Constants of Hill and Michaelis-Menten Equations

The aim of present study was to describe the graphical technique how to go from Hill concentration constant to Michaelis constant. To compare enzymatic processes, the kinetics of which is subjected to different regularities, it is possible to use constants that characterize catalytic activity (Vmax) and concentration constants that are the substrate concentration at which the rate of the enzymatic process is equal to a half of maximum permissible rate. Concentration constants are S0.5 for Hill equation and Km for Michaelis-Menton equation. The graphical approach was proposed in order to go from concentration constant of Hill equation to Michaelis concentration of the process that could be characterized by the same catalytic activity (the same values of minimum and maximum rates) similar to that observed in the process described by Hill equation.