The performance of a weak base anion-exchange resin in removing Orange G dye from aqueous solutions in batch and column system was investigated. The adsorption capacity was found to depend on: pH, dye concentration, contact time, adsorbent dosage, electrolyte presence and temperature. The adsorption equilibrium is best described by the non-linear Langmuir isotherm model. At the optimum pH of 2, the maximum adsorption capacity was 1,076 and 1,218 mg g⁻¹, at 20 and 50°C, respectively. The adsorption kinetics could be described by the pseudo-second-order reaction model. The thermodynamic parameters indicated that adsorption is a spontaneous and endothermic process. FT-IR and SEM analyses provided additional information on adsorption mechanism and on morphological changes of the adsorbent. The breakthrough experimental results were processed by means of Thomas, Yoon–Nelson and Wolborska models. The reusability of the column was examined by conducting several cycles of adsorption and desorption (with 0.05 M NaOH).

The objective of this research was to evaluate some quality-defining physicochemical parameters (moisture, specific gravity, pH, free acidity, ash, electrical conductivity, total phenols, and total flavonoids content, K, Ca, Mg, Na, and P) of seven Romanian monofloral honeys (linden, acacia, rapeseed, sunflower, mint, raspberry, and chestnut) collected in 2017. The investigated quality parameters are mainly within the recommended limits set by standards for honey. Sample analyses indicate the presence of antioxidants, such as TPC (17.9–73.2 mg GAE/100 g) and TFC (0.84–4.81 mg QE/100 g), and high amounts of K (101–1462 mg kg⁻¹), Ca (58.3–167.5 mg kg⁻¹), Mg (24.8–330.6 mg kg⁻¹), Na (94.5–233.3 mg kg⁻¹), and P (34.1–137.2 mg kg⁻¹). The Pearson’s correlations between some parameters (such as color/TFC, color/Mg, color/P, EC/Ash, mm Pfund/TFC, TPC/TFC, K/Ash, P/Mg), together with PCA, HCA, and ANOVA statistics, highlight three main factors that explain the variability in the dataset and could be attributed to stability, mineral, and color/antioxidant contributions. FTIR spectra confirm the authenticity of all the monofloral honeys. The results and data processing confirm the influence of environmental elements (soil, water, air) on the honey composition and highlight the quality of honey, as a complete food and a therapeutic product.

The study of honey in Iasi County reveals its ecological, economic and health importance, emphasizing its unique properties, role in biodiversity and value in promoting sustainable beekeeping and regional identity. This study aimed to investigate the characteristics of honey from Iasi County, Romania, analyzing 27 samples collected in 2020 and 2021. The samples include tilia (8 raw, 7 commercial), acacia (2 raw, 2 commercial), rapeseed (3 raw), sunflower (3 raw) and lavender (2 raw) honey. Analyses were carried out under Romanian/EU standards, assessing parameters such as color, electrical conductivity, moisture, total soluble solids (TSS), acidity (free, lactone, total), pH, hydroxymethylfurfural (HMF), ash and mineral composition (Na, K, Ca, Mg, Cu, Zn, Mn and Fe). The results revealed significant differences between raw and commercial honeys. Notably, in commercial tilia honey, higher values were found for color (38.58 mm Pfund vs. 24.14 mm Pfund), total acidity (25.93 meq·kg⁻¹ vs. 17.36 meq·kg⁻¹) and HMF levels (8.84 mg·kg⁻¹ vs. 3.68 mg·kg⁻¹). Conversely, water-insoluble solids (0.08% vs. 0.15%) and ash content (0.21% vs. 0.30%) were lower in commercial samples. Potassium was the most abundant mineral detected, while copper and zinc levels were the lowest. Significant correlations were observed between several parameters, including ash with electrical conductivity and HMF with acidity. This study underscores the impact of processing on honey quality and highlights the importance of understanding honey composition for consumers and producers alike.

The aim of this research was to evaluate some characteristics (moisture, total solid substances, specific gravity, pH, FA, ash, electrical conductivity, TPC and TFC, potassium, calcium, magnesium, sodium, phosphorus, zinc, copper, manganese, nickel, cobalt, and lead) of fifteen multifloral honey samples. The quality of the investigated honey was confirmed by the obtained results: moisture, FA, and EC values were below the limit value regulated by the legislation. The average content of total polyphenols and total flavonoids of 29.91 mg GAE/100 g and 2.13 mg QE/100 g confirm the antioxidant properties of honey. Determination of minerals showed that potassium (101.4–1212.6 mg kg⁻¹) was the most abundant mineral in honey, followed by sodium (40.7–302.3 mg kg⁻¹) and calcium (41.8–230.9 mg kg⁻¹). Lead was found in two samples, with a content under the limit stipulation by legislation; nickel was found in one sample of 0.10 mg kg⁻¹, and the content of cobalt was below the detection limit. Significant correlations (p < 0.001) were observed between mm Pfund and electrical conductivity, TPC, TFC, P, Ca, and Zn; strong correlations (p < 0.001) were between electrical conductivity with Ash, TPC, TFC, K, and P. FTIR analysis confirmed the differences obtained by analyzing multifloral honey samples.