A method of processing Wasted Electric and Electronic Equipment (WEEE), and the separation of gold that it contains, is presented within the present work. Due to the fact that the amount of Au in real-life secondary resources covers a broad range of concentrations, the applied solutions were obtained by digesting in aqua regia WEEE characterized by relatively high (Central Processing Units, CPU) and relatively low (Pin Contact Elements, PIN) amounts of gold. The investigated systems were received after processes of enrichment and leaching, ignoring the usually applied WEEE processing reduction and solvent-extraction processes, keeping the amount of generated wastes to a minimum. The obtained CPU and PIN solutions were then directly contacted with core–shell type anion exchange resins functionalized using ethylenediamine and 1-(2-aminoethyl)piperazine. Application of the designed polymers allowed the process of aqua regia-leaching, omitting the application of other, more harmful agents. The investigated resins revealed great selectivity towards gold. Despite the fact that the obtained solutions contained only 1.5% (CPU) or 0.1% (PIN) of Au, its removal reached 86% and the logarithms of partition coefficients indicate that affinity of the applied resins to gold is almost ten times greater than the very competitive nickel present in the obtained solutions. Finally, the gold-containing core–shell polymers were effectively eluted, recovering 100% of the taken from the solutions gold

Removal of arsenic from water reservoirs is the issue of great concern in many places around the globe. As adsorption is one of the most efficient techniques for treatment of As-containing media, thus the present study concerns application of iron oxides-hydroxides (akaganeite) as adsorbents for removal of this harmful metal from aqueous solution. Two types of akaganeite were tested: synthetic one (A) and the same modified using hexadecyltrimethylammonium bromide (A_M). Removal of As was tested in batch studies in function of pH, adsorbent dosage, contact time, and initial arsenic concentration. The adsorption isotherms obey Langmuir mathematical model. Adsorption kinetics complies with pseudo-second-order kinetic model, and the constant rates were defined as 2.07 × 10⁻³and 0.92 × 10⁻³ g mg⁻¹ min⁻¹ for the samples (A) and (A_M), respectively. The difference was caused by significant decrease in adsorption rate in initial state of the process carried out for the sample A_M. The maximum adsorption capacity achieved for (A) and (A_M) akaganeite taken from Langmuir isotherm was 148.7 and 170.9 mg g⁻¹, respectively. The results suggest that iron oxides-hydroxides can be used for As removal from aqueous solutions.

Development of efficient plant protection methods against bacterial phytopathogens subjected to compulsory control procedures under international legislation is of the highest concern having in mind expensiveness of enforced quarantine measures and threat of the infection spread in disease-free regions. In this study, fructose-stabilized silver nanoparticles (FRU-AgNPs) were produced using direct current atmospheric pressure glow discharge (dc-APGD) generated between the surface of a flowing liquid anode (FLA) solution and a pin-type tungsten cathode in a continuous flow reaction-discharge system. Resultant spherical and stable in time FRU-AgNPs exhibited average sizes of 14.9 ± 7.9 nm and 15.7 ± 2.0 nm, as assessed by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. Energy dispersive X-ray spectroscopy (EDX) analysis revealed that the obtained nanomaterial was composed of Ag while selected area electron diffraction (SAED) indicated that FRU-AgNPs had the face-centered cubic crystalline structure. The fabricated FRU-AgNPs show antibacterial properties against Erwinia amylovora, Clavibacter michiganensis, Ralstonia solanacearum, Xanthomonas campestris pv. campestris and Dickeya solani strains with minimal inhibitory concentrations (MICs) of 1.64 to 13.1 mg L⁻¹ and minimal bactericidal concentrations (MBCs) from 3.29 to 26.3 mg L⁻¹. Application of FRU-AgNPs might increase the repertoire of available control procedures against most devastating phytopathogens and as a result successfully limit their agricultural impact.