In this work, the authors present the possibility of modification of polymer membranes by TiO₂ + AgO coating created by the magnetron sputtering method. The two-component TiO₂ + AgO coating can improve and shape new functional properties such as bactericidal and photocatalytic properties. The influence of magnetron power changes on the structure of the membrane was investigated as well. The structure and elemental composition of TiO₂ + AgO coatings were analyzed using SEM and EDS technique. All deposited coatings caused a total inhibition of the growth of two investigated colonies of Escherichia coli and Bacillus subtilis on the surface. The photocatalytic properties for membranes covered with oxide coatings were tested under UV irradiation and visible light. The filtration result show that polymer membranes covered with two-component TiO₂ + AgO coatings have a permeate flux similar to the non-coated membranes.

This paper addresses the issue of plasma treatment of the surface of polypropylene (PP) using sputtering of silver (Ag) and copper (Cu) and their oxides with MS-PVD in order to impart antimicrobial activity. It was found that plasma treatment of PP with Cu and Ag based layers allows to provide excellent antimicrobial properties due to a constant release of metal ions. The samples of PP treated with Cu and CuO were characterized by highest antimicrobial properties and stability of the coatings. The most stable and least effective coating against bacteria was Ag-PP sample. In turn, AgO-PP was characterized by the lowest stability in aqueous conditions and strong antimicrobial activity. It was found that leaching of metal ions from the surface of treated PP even in exceptional levels plays a crucial role in bactericidal activity.

A novel approach of the deposition of two-component coating consisting of TiO₂ and CuO on polymer membranes by MS-PVD method was presented in this work. This confirmed the possibility of using thin functional coatings for the modification of polymer membranes. The influence of technological parameters of the coating deposition on the membrane’s structure, chemical composition and functional properties (hydrophilic, photocatalytic and bactericidal properties) were analyzed using SEM. Model microorganism such as Escherichia coli and Bacillus subtilis have been used to check the antibacterial properties. The results indicated that doping with CuO highlights the potential of bactericidal efficiency. The surface properties of the membranes were evaluated with the surface free energy. For evaluating photocatalytic properties, the UV and visible light were used. The filtration tests showed that polymer membranes treated with two-component TiO₂ + CuO coatings have a permeate flux similar to the reference material (non-coated membrane). The obtained results constitute a very promising perspective of the potential application of magnetron sputtering for deposition of TiO₂ + CuO coatings in the prevention of biofouling resulted from the membrane filtration of dairy wastewater.

According to the idea of sustainable development, humanity should make every effort to care for the natural environment along with economic development. Decreasing water resources in the world makes it necessary to take action to reduce the consumption of this resource. This article presents the results of research conducted to improve the use of recyclable materials in line with the circular economy model. The research focused on the development of a technological solution for the recovery of raw materials from galvanic wastewater. The concept of a galvanic wastewater treatment system presented in the article includes wastewater pre-treatment in the ultrafiltration (UF) process and water recovery in the reverse osmosis (RO) process. In addition, the purpose of the work was to manage post-filtration waste (RO retentate) containing high concentrations of zinc in the process of galvanizing metal details. The obtained results indicate that it is possible to reduce the amount of sewage from the galvanizing industry by reusing the recovered water as technical water in the process line. The carried-out model tests of galvanizing confirmed the possibility of using RO retentate for the production of metal parts. The achieved results are a proposal to solve the problem of reducing the impact of galvanic wastewater on the environment and to improve the profitability of existing galvanizing technologies by reducing the consumption of water and raw materials.

This paper presents an investigation into the use of pyrolysis to valorise solid waste in the form of post-consumer footwear uppers. A heterogenous leather and textile mixture is studied, produced by crushing some representative samples of post-consumer footwear uppers. The waste has a low ash content and a high net calorific value, which translates into the high gross calorific value of the material. In addition, it contains relatively little S and Cl, which is promising for its use in the process of pyrolysis. The effect of the pyrolysis temperature on the efficiency of carbonising leather and textile mixtures, their physico-chemical parameters, elemental composition, and structure, as well as the development of a specific surface, is investigated. The research results imply that as the pyrolysis temperature grows, the carbonisation efficiency declines. The produced materials consist primarily of C, O, N, and H, whose contents depend on the pyrolysis temperature. Moreover, all the carbonised materials display the presence of two G and D bands, which is typical for carbon materials. Based on the peak intensities of the bands, I_D/I_G coefficients are calculated to assess the organisation of the materials’ structures. As the pyrolysis temperature rises, the structural organisation declines, contributing to an increased material porosity and, thus, a greater specific surface of the carbonised materials. This study contributes data on the thermal management and pyrolysis of leather and textile waste into useful carbonised materials. Investigating the applicability of carbonised materials is projected as the next stage of research work.