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Magnetic disinfectants were achieved through the polymerization of thiourea and formaldahyde in the presence of magnetite nano particles (MTUF), the as-prepared MTUF was loaded with Ag(I) or Au(III). The obtained disinfectants (MTUF-Ag and MTUF-Au) were test for some selected pathogenic strains deactivation. The toxicity of MTUF before and after Ag(I) or Au(II) loading was estimated. The antimicrobial activity tests of MTUF-Ag and MTUF-Au were carried out against Escherichia coli, Salmonella typhimurium and Pseudomonas aeruginosa as examples of Gram negative bacteria; Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis as examples of Gram positive bacteria; Candida albicans as representative for fungi. The results showed that the minimum inhibitory concentration (MIC) of MTF-Ag against Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus and Candida albicans were 1.5, 2.0, 1.5, 1.0 and 2.5 mg mL−1, respectively after 40 min of contact time. While MTUF-Au showed higher MIC concentrations: 6.0, 4.0, 4.0, 4.0 and 6 mg mL−1 for the mentioned strains, respectively. The studied MTUF-Ag and MTUF-Au were successfully tested for deactivation of the studied pathogenic microorganism’s water and wastewater samples. It can be concluded that, MTUF-Ag and MTUF-Au are good candidates for water disinfection.

Directly, the utilization of petroleum-based fuels for energy supply in numerous applications has led to their depletion accompanied by an increase of global warming to the atmosphere. Hence, the paramount need for exploring new renewable energy sources has become in demand. Believing in the concepts of sustainable development to overcome these issues, the immense waste biomass has been recognized as a promising, clean and viable solution for future energy and fuels. In this regard, this review concisely presents the latest cutting-edge of different integrated refining strategies for the conversion of biomass to valuable liquid fuels (BTL) to reduce the dependency on conventional fuels. Economic insights for the production of biofuels have been distinctively assessed. From the economic point of view, thermochemical conversion methods of biomass to fuel are considered as promising integrated approaches because of their flexibility towards various types of biomasses and their efficiency to produce valuable products such as viable fuels, heat, and electricity. Bibliometric mapping has been thoroughly conducted to identify the latest literature studies within (bioenergy/biofuel) field. Dynamically, future efforts in the biomass management sector are also advised for producing green liquid fuels to meet the global energy demand through large commercial scales.

Microplastics (MPs) have been seen over recent years as a major water contaminant with significant potential for adverse health and animal health effects. Natural attenuation has little impact, and traditional treatment processes are unable to fully eliminate MPs, which have been reported to accumulate in the ecosystem, in aquatic food web species, and humans; Aquatic plants can accumulate MPs in their tissues, thereby possibly transferring the accumulated MPs to higher trophic levels through the food chain. This review provides explanations for the interaction between community composition in the aqueous ecosystem and MPs. MPs could act as vectors for persistent organic/inorganic pollutants in the natural environment. As a result of MPs interaction with pollutants of emerging concern and/or heavy metals, enhanced toxicity has been summarized; MPs can accommodate several contaminants onto their surface due to the high adsorption potentiality. It is imperative to understand the occurrence and prevalence of MPs in the aquatic environment. limitations in reproducing real conditions for MPs occurrence in environmental matrices (composition, size, concentration) was observed due to their interaction with different pollutants, therefore, very few studies have been carried out about MPs remediation, and there is a paucity of information, especially on the designed techniques to remove MPs from wastewater efficiently. Efficient technologies like floatation, filtration, and membrane separation have been discussed considering their merits and demerits.

The adsorption of Cu(II), Cd(II) and Pb(II) from aqueous solution onto methyl methacrylate-Na-Y-Zeolite (MMA-Na-Y-Zeolite) composite was analyzed in a batch system with respect to pH, contact time, initial metal ion concentration, adsorbent dosage and temperature. The sorbent was characterized by FT-IR spectrometry, SEM analysis and X-ray diffraction (XRD). Kinetic profiles are successfully modeled with the pseudo-second order rate equation. The Langmuir, the Dubinin–Radushkevich and Temkin equations fit well-adsorption isotherms of Cu(II) and Cd(II), while the distribution of Pb(II) at equilibrium did not fit any of the studied adsorption isotherms. The change of free energy (ΔG o ), enthalpy (ΔH o ) and entropy (ΔS o ) of adsorption were also evaluated. The thermodynamics of the adsorption Cu(II) and Cd(II) indicated endothermic nature, on the other side exothermic adsorption was recorded for Pb(II). The regeneration efficiency of MMA-Na-Y-Zeolite reached 96.6%, 98.18% and 98.4% for Cu(II), Cd(II) and Pb(II), respectively. The results indicate that MMA-Na-Y-Zeolite composite could be employed as low-cost material for the removal of heavy metals from real water samples.

Bivalve shells of Anadara uropigimelana were firstly tested as a potential biosorbent for methylene blue (MB) recovery from an aqueous solution, Scanning electron microscopy (SEM), energy dispersive X-Ray analysis (EDX), Fourier-transform infrared (FTIR) and zeta potential measurements were used to characterize bivalve shells sorbent. The influence of variables including pH, amount of sorbent, contact time, concentration of the dye and temperature on MB sorption has been investigated. Percentage removal of 93.6% were obtained under optimum conditions of variables (initial pH of 10.4, sorbent dose of 1 g L−1, initial MB concentration of 20 mg L−1, and temperature of 25 ± 1 °C). The sorption of MB dye onto the sorbent could reach equilibrium after 10 min. Equilibrium data were well fitted to the Langmuir model. Sorption isotherm results showed that the maximum sorption capacity of MB by bivalve shells was 1000 μg g−1. Thermodynamic analysis showed that the sorption of MB onto bivalve shells increased with increasing temperature from 25 to 55 °C, indicating the endothermic nature of the sorption process. Meanwhile, the positive values of ΔSo suggest the increased randomness at the solid/solution interface during the MB sorption. The sorbent was successfully tested for color removal from dyeing facility. This work shows that the bivalve shells hold promises acting as effective sorbent to remove dyes in the wastewater.

Chitosan was modified through four different modification routes. First, epichlorohydrine cross-linked Chitosan was grafted with 3-Amino-1,2,4 triazole,5-thiol and melamine to produce RI and RII, respectively. Second, glutaraldehyde cross-linked chitosan was chemically modified using ammonium hydroxide then grafted with 3-Amino-1,2,4 triazole,5-thiol and melamine to produce RIII and RIV, respectively. The prepared polymers were characterized via FTIR, TGA, elemental analysis, water regain and surface area. RIII and RIV shows higher thermal stability, bigger surface area, and lower water regain, than RI and RII. Removal of Reactive Black 5 (RB5) anions from their aqueous solutions were studied using the modified chitosan adsorbents under various parameters such as pH, agitation time, and temperature. The maximum adsorption capacities are 0.492, 0.330, 0.622 and 0.698 mmol g −1 for RI, RII, RIII, and RIV, respectively, at pH 3 and 25 °C. The nature of interaction of RB5 with the adsorbents was identified. Uptake kinetics and adsorption isotherms were modeled using conventional and simple equations: best results were respectively obtained with the pseudo-second order rate equation and the Langmuir equation. The thermodynamic parameters have been calculated: the adsorption is endothermic, spontaneous and contributes to increase the entropy (randomness) of the system. RI and RII gives higher desorption yield than RIII and RIV, this probably due to the presence of the quaternary ammonium moiety in the last two sorbents.

Herein, a novel eco-friendly urea calcium alginate xerogel beads chemically functionalized with Congo red dye (U-CAB-CR1.43) was fabricated on the basis of commercial valorization of two copious waste biomass; Padina boergesenii brown alga and Anadara uropigimelana bivalve shells. The synthesized sorbent was characterized via FT-TR, BET surface area, TGA, SEM and EDX analyses. Sequential sorption capability of as-prepared biosorbent was investigated by appraising its efficiency to capture Cu(II) metal ion under variable operational parameters. Varying of sorbent doses form 0.5 g L−1 to 5 g L−1 was studied. Sorption isotherms, uptake kinetics and thermodynamic studies as prerequisite tools for plausible apprehension of sorption mechanism were also analyzed under optimized pH value (i.e. pH = 6.5). The results revealed that the isotherm profile of U-CAB-CR1.43 fits Langmuir equation with maximum sorption capacity of 6.94 mmol g-1 (441 mg g-1). Kinetic profile was accurately conformed to pseudo-second order rate equation. Thermodynamic function parameters emphasized the endothermic nature of sorption process. Successful desorption scenario using 0.5 mol L−1 of HCl has considerably promoted the spent sorbent to be further used up to four consequent sorption/desorption cycles. Feasibility of productive sorbent to expel Cu(II) from miscellaneous wastewater was successfully researched. To sum up, this study presents an efficient strategy for capturing Cu(II) from miscellaneous wastewater.