A new biosorbent, obtained by chemical modification of lignocellulosic biomass with Al₂O₃, was tested for removal of anionic surfactant sodium dodecylbenzenesulfonate (DBS) from aqueous solution in batch conditions. As a basic lignocellulosic material for chemical modification by Al₂O₃ was used Lagenaria vulgaris shell (LVB). Biosorbent characterization was performed by Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, and X-ray diffraction analysis. Obtained matter showed significant improvement of removal efficiency compared with unmodified biomass. Effect of initial pH value, biosorbent dosage, and initial concentration of DBS on the sorption process was studied. Sorption of DBS onto LVB-Al₂O₃ was highly pH dependent. Complete DBS removal was attained at lower pHs; as pH increased up to 9, DBS removal rapidly decreased. Optimal sorbent dosage was 2 g/dm³. Sorption kinetics followed pseudosecond-order, intraparticle diffusion and Chrastil's models, suggesting that both surface reaction and diffusion were rate-limiting steps. Equilibria experimental results were best fit by Langmuir sorption isotherm models. Maximum sorption capacity of LVB-Al₂O₃ for DBS was found to be 513.28 mg/g. The present study suggests that the chemically modified L. vulgaris shell with Al₂O₃ could be used effectively for the removal of DBS from aqueous solution.

Bismuth basic nitrates (BBNs) were synthesized via an electrochemical method, i.e., by electrodeposition from an acidic solution of bismuth nitrate, followed by thermal treatment in an air environment. For the first time, the influence of various electrochemical parameters on the morphology, crystal structure, and chemical structure of BBNs was examined. The following synthesis parameters were investigated: electrodeposition current density, thermal treatment temperature of the obtained deposit, and working electrode material (cathode). The obtained materials were characterized by SEM-EDX, XRD, FTIR, TG, and N₂ adsorption/desorption methods and were applied for the sorption of the textile dye RB19. The results showed that the electrodeposition current density and thermal treatment temperature affect the surface morphology, chemical composition, and crystal structure of the obtained materials, as well as the RB19 sorption efficiency. On the other hand, the working electrode material does not affect the properties of the synthesized materials mentioned. Kinetic, isotherm, and thermodynamic analysis of the sorption process were also examined.