Search Results (17)

Treating contamination plumes in relatively lower-permeability zones (LPZs) presents a significant challenge for injection-based remediation due to aquifer heterogeneity. Currently, xanthan gum, as a co-remediation agent, has been confirmed to enhance the removal efficiency of contaminants in these zones. However, its associated effects on plume migration remain to be clarified. This study revealed the mechanisms by which xanthan addition enhances the removal rate of perchloroethylene (PCE), as well as its effects on plume migration. The results demonstrated that the injection of xanthan induces adverse migration of contamination plumes. A nonlinear relationship was observed between xanthan concentration, injection rate, and remediation performance. Within the studied range (0 g/L–0.8 g/L; 10 mL/min–40 mL/min), an optimal xanthan concentration (0.8 g/L) and injection rate (25 mL/min) were identified, at which the PCE removal efficiency was significantly improved, and the contamination plume migration was effectively inhibited. For combinations of porous media with a lower permeability contrast, adding xanthan led to better performance. To provide a comprehensive assessment of the remediation performance, four key indicators were proposed: remediation measurement factor, PCE removal rate, sweeping uniformity, and injection pressure. The results identified the optimal remediation conditions: M-F combination with the lowest permeability contrast (4.9), 0.4 g/L xanthan, and an injection rate of 25 mL/min. These findings contribute valuable insights for the formulation of more efficient remediation strategies. Full article

Astringency in persimmon fruit is often eliminated by treatment with gaseous carbon dioxide, dry ice, or alcohol. However, these methods are time-consuming and labor-intensive, and astringency may recur after heat treatment. In this study, a method for easily reducing astringency was investigated by taking advantage of the benefits of combining proteins and polysaccharides. In the first experiment, the protein materials with strong astringency-reducing effects were screened from among 15 protein-rich foods using astringent persimmon juice (APJ), and collagen peptides were found to be highly effective. However, syneresis was observed when 1% collagen peptide powder was added to the astringent persimmon paste (AP). Therefore, in the second experiment, 0.5% collagen peptides (protein) were applied to reduce heating-induced astringency and reversion and 0.5% polysaccharides (guar, and xanthan gums) to maintain color and suppress syneresis. The results demonstrate that the combination of collagen peptide and polysaccharides is optimal for removing astringency in persimmon, inhibiting its recurrence by heating, and maintaining product quality. The results of this study may reduce the labor required for the astringency removal process, broaden the uses of AP, and facilitate the effective utilization of discarded astringent persimmons that do not meet the standards. Full article

In this study, the use of surfactant-free water-in-oil gelled emulsions containing benzyl alcohol (BAl/w) is proposed as an alternative to the more traditional use of organic solvents for removing varnishes. To mitigate the strong swelling and solvent action of benzyl alcohol and protect the paint and the underlying layers, temporary hydrophobization with cyclomethicone D5 has been proposed. The aim of this study was to evaluate the application of BAl/w surfactant-free, constructed with three different gelling agents of the aqueous dispersing phase (xanthan gum, agar-agar, and polyacrylate) on the surface of an oil painting varnished with and without preliminary saturation with D5. The role of pH, which can influence the ionization, and therefore the water solubility of terpene molecules and all other acid species present on the surface, was also studied. Fourier transform infrared (FT-IR) and Raman spectroscopies were used to characterize the pigments and the surface before and after varnish removal. Elemental analysis and any morphological changes were evaluated using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The leaching efficiency of each surfactant-free emulsion applied on the paint surface was evaluated using a gas chromatography/mass spectroscopy (GC/MS) analysis: the fatty acid content was established in each sample before and after the treatments. Full article

Cleansing products, particularly innovative cosmetic foams, must efficiently remove impurities with minimal impact on the skin barrier and have a favorable sensory profile. The choice of product ingredients is crucial to ensure the optimal characteristics. The current study aims to provide a comprehensive framework for understanding the variability in the characteristics of a cleansing foam to achieve desired properties. The novelty of this study lies in the combination of ingredients for their potential synergistic and complementary effects in cleansing dry skin, as well as the application of Quality by Design (QbD) elements to develop and optimize the formulation of cleansing foam. The effects of varying the concentration of mild surfactants, polyols, and gel-forming agents on the properties of the gels and of the generated foams were studied. Significant influences of the formulation factors were observed: an increased ratio of xanthan gum positively impacted the texture properties of the gel, whereas higher concentrations of surfactants had a negative impact on these parameters. Additionally, increasing the polyols ratio was found to negatively influence the foaming property and stability of the foam. The study established an optimal formulation of a cleansing foam with a ratio of 0.45% xanthan gum, 26.19% surfactants and 2.16% polyols to be used for dry skin hygiene. Full article

The demand for gluten-free products has increased due to improved diagnoses and awareness of gluten-related issues. This study investigated the effect of HPMC, psyllium, and xanthan gum in gluten-free bread formulations. Three tests were conducted, varying the amount of these ingredients: in the first formulation, the amount of HPMC was increased to 4.4 g/100 g of flour and starch; in the second, psyllium husk fiber was increased to 13.2 g/100 g of flour and starch; and in the third formulation, xanthan gum was removed. Differences were observed among the formulations: increasing HPMC reduced extrusion force without affecting bread quality; adding psyllium increased dough elasticity but also crumb gumminess and crust hardness. Eliminating xanthan gum altered dough rheology, resulting in a softer and less gummy crumb, and a less reddish color in the final bread. Full article

Recently, hand sanitization has gained attention for preventing disease transmission. Many on-the-market convenient dermal sanitizers contain alcohol, which can be detrimental to the skin. Therefore, three nanoemulgel formulations (LN-F1, LN-F2, LN-F3) incorporating lemon peel extract (LE), and with various increasing concentrations of xanthan gum as a gelling agent and stabilizer, were developed and characterized as a novel alternative. All formulations showed non-Newtonian shear-thinning flow behavior, particle size values below 200 nm, and increasing zeta potential with higher xanthan gum concentrations. All nanoemulgel formulations exhibited greater in vitro phenolic compound release than free LE. LN-F2 (1.0% LE, 20.0% mineral oil, 20.0% Span 80, 4.0% Cremophor RH 40, 4.0% PEG 400, 0.5% xanthan gum, 50.5% dH₂O) was selected as the optimal formulation due to improved characteristics. LE and LN-F2 potential cytotoxicity was assessed on MA-104, showing no significant cellular morphological alterations up to 10 mg/mL for both samples. LN-F2 showed in vitro antimicrobial activity against E. coli, S. Typhimurium, P. aeruginosa, S. aureus, L. monocytogenes, and C. albicans, as well as antiviral activity against phiX 174, but no effect against rotavirus (SA-11). In vivo, LN-F2 presented a removal capacity of 83% to 100% for bacteria and 89% to 100% for fungi. These findings suggest that the formulated nanoemulgel holds potential as a safe and effective antiseptic, providing a viable alternative to commercial alcohol-based formulations. Full article

Gluten-free bread is a new option for a population unable to digest gliadins and glutenins. This study compared the texture and color of four formulations, each containing varying amounts of hydroxypropyl methylcellulose (HPMC), psyllium, xanthan gum, and water. It was found that removing xanthan gum reduced the hardness and gumminess of the breadcrumbs. Increasing the amount of psyllium increased gumminess and redness. Interestingly, increasing the amount of HPMC in the formulation did not show significant differences. This suggests that HPMC may not have a pronounced effect on texture and color compared to the control formulation. Full article

In order to solve the problem of the low removal efficiency of fine particles in the flue gases of the metallurgy process, a chemical agglomeration pretreatment method was studied. The coagulant solution of xanthan gum, konjac gum, and their mixtures was selected to research the reunion effects of and the efficiency of gravitational dust removal of fine dust in the gas of the converter flue using a self-built experimental platform. Moreover, the effects of wetting agent type, dust concentration, pressure, and flue gas velocity on the fine grain removal efficiency were investigated. The results showed that the mixed solution of 1 g/L mixed gum and 0.5 g/L SDS had the most obvious effect on the particle size increasing of fine dust particles and the best removal effect when the flue gas velocity was 10 m/s. There was a peak particle size of 85.32 μm increased about eight times larger, and the removal efficiencies reached 51.46% for PM₂.₅ and 53.13% for PM₁₀. The Box–Behnken experimental design combined with a response surface analysis method was used to optimize the parameters of the mixed gum concentration, pressure, and flue gas velocity. The optimal removal conditions were 1 g/L, 0.4 MPa, and 10 m/s. The results of this study can provide efficient methods and technical support for pre-processing and efficient removal of fine particles in heavy-polluting industries such as steel making. This will promote the green development of the metallurgical industry. Full article

In recent years, multidrug-resistant bacteria have developed the ability to resist multiple antibiotics, limiting the available options for effective treatment. Raising awareness and providing education on the appropriate use of antibiotics, as well as improving infection control measures in healthcare facilities, are crucial steps to address the healthcare crisis. Further, innovative approaches must be adopted to develop novel drug delivery systems using polymeric matrices as carriers and support to efficiently combat such multidrug-resistant bacteria and thus promote wound healing. In this context, the current work describes the use of two biocompatible and non-toxic polymers, poly(vinyl alcohol) (PVA) and xanthan gum (XG), to achieve hydrogel networks through cross-linking by oxalic acid following the freezing/thawing procedure. PVA/XG-80/20 hydrogels were loaded with different quantities of neomycin sulfate to create promising low-class topical antibacterial formulations with enhanced antimicrobial effects. The inclusion of neomycin sulfate in the hydrogels is intended to impart them with powerful antimicrobial properties, thereby facilitating the development of exceptionally efficient topical antibacterial formulations. Thus, incorporating higher quantities of neomycin sulfate in the PVA/XG-80/20-2 and PVA/XG-80/20-3 formulations yielded promising cycling characteristics. These formulations exhibited outstanding removal efficiency, exceeding 80% even after five cycles, indicating remarkable and consistent adsorption performance with repeated use. Furthermore, both PVA/XG-80/20-2 and PVA/XG-80/20-3 formulations outperformed the drug-free sample, PVA/XG-80/20, demonstrating a significant enhancement in maximum compressive stress. Full article

The removal of pharmaceutical contaminants from wastewater has gained considerable attention in recent years, particularly in the advancements of hydrogel-based adsorbents as a green solution for their ease of use, ease of modification, biodegradability, non-toxicity, environmental friendliness, and cost-effectiveness. This study focuses on the design of an efficient adsorbent hydrogel based on 1% chitosan, 40% polyethylene glycol 4000 (PEG4000), and 4% xanthan gum (referred to as CPX) for the removal of diclofenac sodium (DCF) from water. The interaction between positively charged chitosan and negatively charged xanthan gum and PEG4000 leads to strengthening of the hydrogel structure. The obtained CPX hydrogel, prepared by a green, simple, easy, low-cost, and ecological method, has a higher viscosity due to the three-dimensional polymer network and mechanical stability. The physical, chemical, rheological, and pharmacotechnical parameters of the synthesized hydrogel were determined. Swelling analysis demonstrated that the new synthetized hydrogel is not pH-dependent. The obtained adsorbent hydrogel reached the adsorption capacity (172.41 mg/g) at the highest adsorbent amount (200 mg) after 350 min. In addition, the adsorption kinetics were calculated using a pseudo first-order model and Langmuir and Freundlich isotherm parameters. The results demonstrate that CPX hydrogel can be used as an efficient option to remove DCF as a pharmaceutical contaminant from wastewater. Full article

Increases in community and industrial activities have led to disturbances of the environmental balance and the contamination of water systems through the introduction of organic and inorganic pollutants. Among the various inorganic pollutants, Pb (II) is one of the heavy metals possessing non-biodegradable and the most toxic characteristics towards human health and the environment. The present study is focussed on the synthesis of efficient and eco-friendly adsorbent material that can remove Pb (II) from wastewater. A green functional nanocomposite material based on the immobilization of α-Fe₂O₃ nanoparticles with xanthan gum (XG) biopolymer has been synthesized in this study to be applied as an adsorbent (XGFO) for sequestration of Pb (II). Spectroscopic techniques such as scanning electron microscopy with energy dispersive X-ray (SEM-EDX), Fourier transform infrared (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), ultraviolet visible (UV-Vis) and X-ray photoelectron spectroscopy (XPS) were adopted for characterizing the solid powder material. The synthesized material was found to be rich in key functional groups such as –COOH and –OH playing important roles in binding the adsorbate particles through ligand-to-metal charge transfer (LMCT). Based on the preliminary results, adsorption experiments were conducted, and the data obtained were applied to four different adsorption isotherm models, viz the Langmuir, Temkin, Freundlich and D–R models. Based on the high values of R² and low values of χ², the Langmuir isotherm model was found to be the best model for simulation of data for Pb (II) adsorption by XGFO. The value of maximum monolayer adsorption capacity (Q_m) was found to be 117.45 mg g⁻¹ at 303 K, 126.23 mg g⁻¹ at 313 K, 145.12 mg g⁻¹ at 323 K and 191.27 mg g⁻¹ at 323 K. The kinetics of the adsorption process of Pb (II) by XGFO was best defined by the pseudo-second-order model. The thermodynamic aspect of the reaction suggested that the reaction is endothermic and spontaneous. The outcomes proved that XGFO can be utilized as an efficient adsorbent material for the treatment of contaminated wastewater. Full article

Wet electrostatic precipitators (WESPs) are increasingly used in iron and steel plants and coal-fired power plants due to their higher efficiency at capturing fine particles than conventional dry-type precipitators. In order to achieve ultra-pure purification of dust in steel plant gas, we propose an improved method that involves adding a chemical coagulant and a surfactant to a WESP. The effects of the type and concentration of chemical coagulant and surfactant on the agglomeration effect and dust removal efficiency of blast furnace dust were investigated. The results show that the addition of a chemical coagulant could promote the agglomeration of blast furnace dust particles, and the D₅₀ of dust particles increased from 5.8 to 15.0 μm after the addition of xanthan gum (XTG). The best increase in the blast furnace’s dust particle removal occurred at a concentration of 10 mg/L of XTG, and the dust removal efficiency reached 97.59%. The surfactant dodecyl trimethyl ammonium chloride (DTAC) improved the dust removal efficiency of blast furnace dust when added alone. The dust removal efficiency reached 97.82% when 10 mg/L of XTG and 9 mg/L of DTAC were added synergistically. The addition of a chemical coagulant and surfactant promoted the agglomeration of blast furnace dust and enhanced the dust capture effect of a WESP. We thus demonstrated that we can improve the efficiency of WESP in the future via chemical coagulation. The authors will further study the effect of multi-factor synergistic coupling on the chemical coagulation method in WESPs. Full article

Mucilage-based flocculants are an alternative to synthetic flocculants and their use in sustainable water treatment relates to their non-toxic and biodegradable nature. Mucilage extracted from flaxseed (FSG) and fenugreek seed (FGG) was evaluated as natural flocculants in a coagulation–flocculation (CF) process for arsenic removal, and were compared against a commercial xanthan gum (XG). Mucilage materials were characterized by spectroscopy (FT-IR, ¹³C NMR), point-of-zero charge (pH_pzc) and thermogravimetric analysis (TGA). Box–Behnken design (BBD) with response surface methodology (RSM) was used to determine optimal conditions for arsenic removal for the CF process for three independent variables: coagulant dosage, flocculant dosage and settling time. Two anionic systems were tested: S1, roxarsone (organic arsenate 50 mg L⁻¹) at pH 7 and S2 inorganic arsenate (inorganic arsenate 50 mg L⁻¹) at pH 7.5. Variable arsenic removal (RE, %) was achieved: 92.0 (S1-FSG), 92.3 (S1-FGG), 92.8 (S1-XG), 77.0 (S2-FSG), 69.6 (S2-FGG) and 70.6 (S2-XG) based on the BBD optimization. An in situ kinetic method was used to investigate arsenic removal, where the pseudo-first-order model accounts for the kinetic process. The FSG and FGG materials offer a sustainable alternative for the controlled removal of arsenic in water using a facile CF treatment process with good efficiency, as compared with a commercial xanthan gum. Full article

Osmotic dehydration kinetics depends on food tissue microstructure; thus, modulation of mango porosity could help selectively enhance water removal over sugar gain. In this present study, pretreatments of freeze-thawing (freezing at −36 °C for 2 weeks and thawing at 4 °C for 24 h) and pulsed electric field (1 kV/cm, 10 and 30 pulse numbers), were applied to mango 1 cm-thickness slices prior to osmotic dehydration conducted at 40 °C for 4 h. Three different 60 °Brix agave syrup solutions with or without added polysaccharides (inulin or xanthan gum) were used in the osmotic dehydration operation. Water loss (WL), sugar gain (SG) and microstructure images were used to compare the effects of pretreatments on mango osmotic dehydration efficiency. Results indicated that pulsed electric field (PEF) pretreatment increased slightly WL during osmotic dehydration, contrary to freeze-thawing (F-T), which for most cases led to a decrease. As for solids uptake, due to higher damage induced by F-T to mango tissue, SG was higher than for fresh and PEF pretreated mangoes. Using xanthan gum as additive to agave syrup solution, helped to decrease sugar uptake in frozen-thawed mango due to an increase in solution viscosity. A similar WL/SG ratio was obtained with frozen-thawed mango in solution with xanthan gum. Therefore, in the case of frozen-thawed mango, it is recommended to use an osmotic solution with high viscosity to obtain low sugar uptake in the final product. The novelty of this contribution is twofold: (i) using pretreatments (F-T or PEF) to minimize sugar uptake during osmotic dehydration, and (ii) using agave syrup with added polysaccharides to enrich final product with inulin. Full article

The present research demonstrates the facile fabrication of xanthan gum-cl-poly(acrylamide-co-alginic acid) (XG-cl-poly(AAm-co-AA)) hydrogel by employing microwave-assisted copolymerization. Simultaneous copolymerization of acrylamide (AAm) and alginic acid (AA) onto xanthan gum (XG) was carried out. Different samples were fabricated by changing the concentrations of AAm and AA. A sample with maximum swelling percentage was chosen for adsorption experiments. The structural and functional characteristics of synthesized hydrogel were elucidated using diverse characterization tools. Adsorption performance of XG-cl-poly(AAm-co-AA) hydrogel was investigated for the removal of noxious cadmium (Cd(II)) ions using batch adsorption from the aqueous system, various reaction parameters optimized include pH, contact time, temperature, and concentration of Cd(II) ions and temperature. The maximum adsorption was achieved at optimal pH 7, contact time 180 min, temperature 35 °C and cadmium ion centration of 10 mg·L⁻¹. The XG-cl-poly(AAm-co-AA) hydrogel unveiled a very high adsorption potential, and its adsorption capacities considered based on the Langmuir isotherm for Cd(II) ions was 125 mg·g⁻¹ at 35 °C. The Cd(II) ions adsorption data fitted nicely to the Freundlich isotherm and pseudo-first-order model. The reusability investigation demonstrated that hydrogel retained its adsorption capacity even after several uses without significant loss. Full article