This study explores the synergistic potential of ladle slag (LS) and sunflower shell fly ash (SSFA) in alkali-activated binder systems, focusing on their chemical and mineralogical characteristics and the influence of SSFA addition on the mechanical performance of LS-based pastes. X-ray fluorescence and XRD analysis revealed that LS is rich in CaO and latent hydraulic phases such as γ-belite and mayenite, while SSFA is dominated by K₂O, SO₃, and KCl/K₂SO₄ phases, reflecting its biomass origin. Infrared spectroscopy and thermal analysis confirmed the presence of carbonate, hydroxide, and hydrate phases, with SSFA exhibiting more complex thermal behavior due to volatile-rich composition. When used alone, LS produced weak binders; however, a 10 wt% SSFA addition tripled compressive strength to nearly 30 MPa, indicating a significant activation effect. Further increases in SSFA content led to strength reduction, likely due to increased porosity and excess salts. Microstructural analysis showed that SSFA promotes the formation of AFm phases such as Friedel’s salt and hydrocalumite, altering hydration pathways and enhancing early strength through chemical activation and carbonation processes. The findings highlight the potential of combining LS and SSFA as a sustainable binder system, offering a waste-derived alternative for low-carbon construction materials.

The present study focuses on the adsorption of Pb(II) by the H-form of titanosilicates (ETS-4, GTS-1) and clinoptilolite. The H-forms were prepared by first exchanging the extra-framework cations—Na⁺, K⁺, Ca²⁺, etc.—with NH₄⁺, and by subsequent thermal treatment for obtaining H-forms. The purity and thermal behaviour of the initial, NH₄⁺, and H-forms of ETS-4, GTS-1, and clinoptilolite were analysed by powder XRD, while the morphology and size of the particles were determined by SEM. The chemical composition of the solids and the solutions was obtained by WDXRF and ICP-OES, respectively. The kinetics research of the Pb(II) adsorption processes was based on WDXRF and ICP-OES. The H-forms of the materials displayed favourable properties for the adsorption of Pb(II). The best behaviour in this respect was demonstrated by GTS-1 when compared to ETS-4 and clinoptilolite.

This study explores the synergistic potential of ladle slag (LS) and sunflower shell fly ash (SSFA) in alkali-activated binder systems, focusing on their chemical and mineralogical characteristics and the influence of SSFA addition on the mechanical performance of LS-based pastes. X-ray fluorescence and XRD analysis revealed that LS is rich in CaO and latent hydraulic phases such as γ-belite and mayenite, while SSFA is dominated by K₂O, SO₃, and KCl/K₂SO₄ phases, reflecting its biomass origin. Infrared spectroscopy and thermal analysis confirmed the presence of carbonate, hydroxide, and hydrate phases, with SSFA exhibiting more complex thermal behavior due to volatile-rich composition. When used alone, LS produced weak binders; however, a 10 wt% SSFA addition tripled compressive strength to nearly 30 MPa, indicating a significant activation effect. Further increases in SSFA content led to strength reduction, likely due to increased porosity and excess salts. Microstructural analysis showed that SSFA promotes the formation of AFm phases such as Friedel’s salt and hydrocalumite, altering hydration pathways and enhancing early strength through chemical activation and carbonation processes. The findings highlight the potential of combining LS and SSFA as a sustainable binder system, offering a waste-derived alternative for low-carbon construction materials.

The results of preliminary studies of Bulgarian natural raw materials as possible sources for the synthesis of high-quality ceramics of the “yellow” pavers type are presented. For the purposes of comparative analysis, a short geological-mineralogical literature review of Bulgarian and Hungarian deposits of marl raw materials and of Bulgarian deposits of non-marl raw materials rich in magnesium is made. The capabilities of the X-ray fluorescence (XRF) analysis and the powder X-ray diffraction (PXRD) techniques for the rapid acquisition of reliable data on the phase-chemical characteristics of the investigated materials have been demonstrated. A relation is made between these characteristics and the physicochemical and mechanical properties of possibly synthesized products (color, hardness, etc.). Considerations for choosing methods for processing the primary data are presented, allowing for some simplification without affecting the reliability of the results. The latter have been analyzed and possibilities for improving the qualities of the starting raw material have been discussed in order to obtain products with desired characteristics.

For the first time, this study investigates in vivo the potential of Na-modified natural clinoptilolite to mitigate cadmium toxicity in ICR mice, a model relevant to human health. We enhanced natural clinoptilolite to improve its cadmium (Cd) exchange capacity. Mice were exposed to environmentally realistic cadmium nitrate Cd(NO₃)₂ doses in their drinking water. The detoxification efficacy of the mineral was evaluated over 45 days in four groups: control (no supplementation), Cd(NO₃)₂ only, clinoptilolite only, and a combination of Cd(NO₃)₂ and clinoptilolite. We assessed Cd bioaccumulation in the liver and kidneys, genotoxicity (micronucleus assay), hematological parameters, and oxidative stress markers. Cd exposure resulted in significant bioaccumulation, reduced growth, changes in erythrograms, DNA damage, and oxidative stress. Mice receiving clinoptilolite alone showed a significant increase in body mass. Modified clinoptilolite led to a nearly 48% reduction in Cd accumulation and a 30% increase in Cd excretion in the Cd-plus-clinoptilolite group compared to the Cd-only group. Erythrogram and leukogram parameters returned to near-normal levels, with reductions in malondialdehyde (MDA) and increases in glutathione (GSH) observed by the end of the experiment. No elevated levels of micronuclei were found following clinoptilolite supplementation. These results suggest that modified clinoptilolite may be a cost-effective detoxifier in Cd-polluted regions.

The present work focuses on the removal of dyes from polluted water, and, more precisely, the targets are crystal violet (CV) and methylene blue (MB). For this purpose, a series of Zr-modified catalysts based on microporous Engelhard Titanium Silicate 10 (ETS-10) were developed and synthesized. Aiming at improvement in the photodegradation efficiency and stability of ETS-10, Zr centers replacing part of Ti ones were introduced during the synthesis procedure. The obtained Na-K-ETS-10/xZr catalysts were characterized by X-ray powder diffraction (XRD), wavelength dispersive X-ray fluorescence (WDXRF), N₂ physisorption and Fourier transform infrared spectroscopy (FTIR). The photocatalytic properties of Na-K-ETS-10/xZr- (x = 5, 10, 15 and 20 wt% Zr) catalysts were studied in terms of water purification from crystal violet and methylene blue. The Na-K-ETS-10/xZr wt% x = 6 catalyst appeared to be the most efficient in the photodegradation of CV and MB, removing nearly 100% of the dyes. Kinetic studies showed that the removal of CV and MB is a rapid process and one, which obeys the non-linear pseudo-second-order model.