Comparison the Adsorption Capacity of Ukrainian Tuff and Basalt with Zeolite–Manganese Removal from Water Solution

Manganese is an undesirable element in tap water but is common in the groundwater. Several methods can be used for manganese removal, including adsorption. Mined rocks are commonly evaluated as adsorbents and it was the objective of this paper – to investigate the Ukrainian volcanic tuff and basaltic rock from the Ivanodolinsky quarry and compare it with Ukrainian zeolite as well as with literature data. The research was based on equilibrated batch tests at a temperature of 10°C and slightly acidic pH. The data were treated using Langmuir and Freundlich models in the linear form. The results indicated the spontaneous and favourable adsorption of manganese. The volcanic tuff was characterized by the highest adsorption capacity, twice higher than basalt and zeolite. The heterogeneity of the active adsorption sites on the tuff was also greater and resulted from the diversity of the mineral composition. Considering the literature data, the properties of tuff are worth further research

Technological Conditions for the Coagulation of Wastewater from Cosmetic Industry

Coagulation is often used for the pre-treatment of industry wastewater, with effectiveness strictly dependent on technological conditions. This study aimed to determine what technological parameters of coagulation of cosmetic industry wastewater provided the highest efficiency of clarification. The dosages of reagents, the order of dosing, as well as the one- and two-stage processes were investigated. Samples of raw wastewater were collected from average daily effluent from a cosmetics manufacturing plant. Liquid coagulant PIX 111 (FeCl3) and NaOH as a pH-adjusting agent were used. Jar-test experiments were carried out to determine the optimum conditions for turbidity and total organic carbon (TOC) removal. The efficiency of clarification was high (90–99%) across a wide range of pH values (6–9) and coagulant doses (0.5–1.25 mL/L). What is important, the coagulant dose of 0.56 mL/L provided 97.6 % clarification efficiency without the addition of the alkali. The minimal stoichiometric excess of alkalinity for effective coagulation was 0.5 mmol/L. In all samples, the removal efficiency for TOC was lower than for turbidity, because some of the organic carbon forms were non-coagulating dissolved compounds. The wastewater from tonic and fluid production was very susceptible to coagulation. The addition of the coagulant before the alkali resulted in better wastewater treatment efficiency than the reverse order. Single-stage process with optimal doses of the reagents allowed to clarify wastewater to a level of 10 NTU. On the other hand, the two-stage process brought the turbidity down to 1 NTU level

The Kinetics of Manganese Sorption on Ukrainian Tuff and Basalt—Order and Diffusion Models Analysis

The study aimed to determine the nature of the kinetics of the manganese sorption process on Ukrainian tuff and basalt at different temperatures characteristic of the natural water environment. The scope of the research included manganese sorption kinetic test on natural mineral sorbents at temperatures of 10, 17.5 and 25 °C in slightly acidic conditions. Sorption (pseudo-first order, pseudo-second order and Elovich models) and diffusion kinetic models (liquid film diffusion and intraparticle diffusion) were used in the analysis of test results. The manganese sorption process on both tuff and basalt proceeded quickly. The dynamic equilibrium state of manganese sorption settled after 35 and 45 min on tuff and basalt respectively. Although the process took place in a slightly acidic environment and below pHPZC of the sorbents, possible electrostatic repulsion did not inhibit the removal of Mn. The Mn sorption on both materials followed the PSO kinetics model. Based on the diffusion kinetic models, it was determined that Mn sorption process on both materials was influenced by diffusion through the boundary layer and intraparticle diffusion. The differences in removal efficiency and rate of Mn sorption in the temperature range of 10–25 °C were not found