Colloids Interfaces, Volume 8, Issue 5 (October 2024) – 3 articles

It is imperative to eliminate heavy metals and pharmaceutical residual pollutants from wastewater to reduce their detrimental effects on the environment. In this work, natural zeolite and a 2-amino terephthalic acid-based multi-metallic organic framework were used to create a new composite that can be utilized as an adsorbent for cadmium and safinamide. The adsorption study was examined in a variety of settings (pH, adsorbent dosage, pollutant concentration, and time). Moreover, Zeta potential, BET, SEM, FTIR, XRD, and SEM measurements were used to characterize the adsorbents. The adsorption process was confirmed using FTIR, XRD, and SEM analysis. Various nonlinear adsorption isotherm models were applied to adsorption results. The results showed a significantly better adsorption ability for safinamide and cadmium using zeolite/MOF compared to zeolite. Adsorption kinetics were represented by five models: pseudo first-order, pseudo second-order, intraparticle diffusion, mixed first- and second-order, and the Avrami model. Regarding both adsorbent substances, safinamide adsorption was best represented by the intraparticle diffusion model. In contrast, the pseudo second-order and intraparticle diffusion models for zeolite and zeolite/MOF, respectively, better fit the experimental results in the case of cadmium adsorption. The thermodynamic parameters ΔH°, ΔS°, and ΔG° were investigated through temperature tests carried out at 25, 35, 45, and 55 °C. Exothermic and spontaneous adsorption processes were demonstrated by the computed values. The study of adsorbent regeneration involved the use of several chemical solvents. The DMSO solvent was shown to have the highest adsorbent regeneration method efficiency at 63%. Safinamide elimination was lessened by organic interfering species like cefixime and humic acid compared to inorganic species like chloride, sulphate, and nitrate, most likely as a result of intense competition for the few available active sites. Using zeolite/MOF nanocomposite, the percentage of safinamide removed from spiked real water samples (tap water, Nile River water, and groundwater samples) was 48.80%, 64.30%, and 44.44%, respectively. Based on cytotoxicity results, the highest percentages of cell viability for zeolite and zeolite/MOF at 24 h were 83% and 81%, respectively, in comparison to untreated controls. According to these results, zeolite and zeolite/MOF composites can be used as effective adsorbents for these pollutants in wastewater. Full article

4-Nitroaniline (PNA) is a toxic organic compound commonly found in wastewater, posing significant environmental concerns due to its toxicity and potential carcinogenicity. In this study, the recovery of PNA from aqueous solutions was investigated using a supported liquid membrane (SLM). The membrane, which consists of polypropylene Celgard 2500 (PP-Celg), was embedded with the extractant tributyl phosphate (TBP). Various factors influencing the efficiency of PNA transportation were studied, including the concentration of PNA in the source phase, pH of the source phase, NaOH concentration in the receiving phase, and choice of stripping agents. Optimal conditions for the experiment were determined to be a source phase PNA concentration of 20 ppm at pH 7, distilled water as the receiving phase, TBP as the carrier in the organic phase, and a transport time of 8 h. The extraction process was conducted under ambient temperature and pressure conditions, yielding results indicative of a first-order linearized reaction. Additionally, membrane stability and liquid membrane loss were evaluated. Full article

As the information age progresses, the electronics industry is evolving towards smaller and more sophisticated products. However, electrostatic potentials easily penetrate these components, causing damage. This underscores the urgent need for materials with superior antistatic properties to safeguard electronic devices from such damage. Antistatic coatings typically rely on polymers as the primary material, enhanced with conductive fillers and additives to improve performance. Despite significant progress, these coatings still face challenges related to advanced processing technologies and the integration of electrical and mechanical properties. Among various conductive fillers, the conducting polymer PEDOT:PSS stands out for its exceptional conductivity, environmental stability, and long cycle life. Additionally, epoxy resin (EP) is widely utilized in polymer coatings due to its strong adhesion to diverse substrates during curing. Here, we develop highly conductive and strongly adhesive PEDOT:PSS inks by combining PEDOT:PSS with EP using a composite engineering approach. These inks are used to fabricate PEDOT:PSS coatings by direct ink writing (DIW). We systematically evaluate the DIW of PEDOT:PSS-EP coatings, which show high electrical conductivity (ranging from 0.59 ± 0.07 to 41.50 ± 3.26 S cm⁻¹), strong adhesion (ranging from 15.84 ± 2.18 to 99.3 ± 9.06 kPa), and robust mechanical strength (8 MPa). Additionally, we examine the surface morphology, wettability, and hardness of the coatings with varying PEDOT:PSS content. The resultant coatings demonstrate significant potential for applications in antistatic protection, electromagnetic shielding, and other flexible electronic technologies. Full article