In this work, the potential adsorption abilities of mineral materials such as zeolite (Ze), halloysite (Ha), chalcedonite (Ch), and Devonian sand (DS) used as low-cost resources for the removal of Rhodamine B (RhB) from aqueous solutions were investigated in batch conditions. Adsorption kinetics and equilibrium and the effect of solution reaction (pH) were studied. Adsorption kinetic data were analyzed using two kinetic models: pseudo-first-order and pseudo-second-order models. Adsorption kinetics was better represented by the pseudo-second-order model. Equilibrium data were analyzed by the Freundlich, Langmuir, and Sips isotherms. The results show that equilibrium data fit well with the Freundlich equilibrium. Monolayer maximum adsorption capacities of RhB were assumed at 6.964, 4.252, 2.701, and 0.349 mg/g for Ze, Ha, Ch, and DS, respectively. Adsorption was strongly pH-dependent. The maximum RhB adsorption on all tested materials was observed at pH = 2.2 and decreased with further pH increase. The results of these investigations suggest that natural materials represented by certain minerals have a good potential for the removal of Rhodamine B from aqueous solutions. Graphical Abstract

Express roads are a potential source of heavy metal contamination in the surrounding environment. The Warsaw Expressway (E30) is one of the busiest roads in the capital of Poland and cuts through the ecologically valuable area (Mazowiecki Natural Landscape Park). Soil samples were collected at distances of 0.5, 4.5 and 25 m from the expressway. The concentrations of cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) were determined in the soils by the flame atomic absorption spectrometry method (FAAS). Soils located in the direct proximity of the analyzed stretch of road were found to have the highest values of pH and electrical conductivity (EC), which decreased along with an increase in the distance from the expressway. The contents of Cd, Cu and Zn were found to be higher than Polish national averages, whereas the average values of Ni and Pb were not exceeded. The pollution level was estimated based on the geo-accumulation index (I_geo), and the pollution index (PI). The results of I_geo and PI indexes revealed the following orders: Cu < Zn < Ni < Cd < Pb and Cu < Ni < Cd < Zn < Pb, and comparison with geochemical background values showed higher concentration of zinc, lead and cadmium.

This article focuses on the impact of fly ash from the combustion of municipal sewage sludge (FAMSS) as a cement additive in the amounts of 5%, 10%, 15%, 20% and 25% (by mass) on selected concrete properties. In the course of the experimental work, water penetration depth and compressive strength measurements were made at various periods of curing (from 2 to 365 days). In addition, the potential impact of FAMSS on the natural environment was examined by determining the leachability of heavy metals. FAMSS-modified concretes showed small values of water penetration depth (lower than 50 mm), as well as good compressive strength (reaching minimum class C30/37 after 130 days of maturing)—similar to the compressive strength obtained for conventional concrete. In addition, the partial replacement of cement with FAMSS has environmental benefits, expressed as a reduction in CO₂ emissions. In addition, study has shown that compliance with environmental requirements is associated with heavy metal leaching.