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This reported work aims to fabricate an eco-friendly Zr bio-based MOF and assessment its adsorption efficiency towards the cationic and anionic dye pollutants including methylene blue (MB) and direct red 81 (DR-81), respectively. Also, its adsorption tendency for the highly toxic heavy metal of hexavalent chromium (Cr(VI)) was compared with dyes. The adsorption performance of bio-MOF showed that the maximum monolayer adsorption capacities were recorded as 79.799 mg/g for MB, 36.071 mg/g for DR-81, and 19.012 mg/g for Cr(VI). Meanwhile, the optimum dosage of as-synthesized MIP-202 bio-MOF was 0.5, 1, and 2 g L−1 for MB, DR-81, and Cr(VI), respectively. Thermodynamic analysis demonstrated the spontaneous, thermodynamically, and endothermic nature of the decontamination processes onto the fabricated Zr bio-based MOF. The adsorption data were fitted by Langmuir isotherm model compared with Freundlich and Temkin models for all studied water pollutants. Pseudo-second-order kinetic model was a fit model for description of the adsorption kinetics of the different cationic and anionic pollutants onto Zr bio-based MOF. These outcomes indicated that Zr bio-based MOF has potential application for adsorption of different types of industrial water pollutants including cationic and anionic dyes and heavy metals.

Bacterial nanocellulose (Bnc) has been drawing enormous attention because of its versatile properties. Herein, we shed light on the BNC production by a novel bacterial isolate (MD1) utilizing various agroindustrial wastes. Using 16S rRNA nucleotide sequences, the isolate was identified as Komagataeibacter saccharivorans MD1. For the first time, BNC synthesis by K. saccharivorans MD1 was investigated utilizing wastes of palm date, fig, and sugarcane molasses along with glucose on the Hestrin-Schramm (HS) medium as a control. After incubation for 168 h, the highest BNC yield was perceived on the molasses medium recording 3.9 g/L with an initial concentration of (v/v) 10%. The physicochemical characteristics of the BNC sheets were inspected adopting field-emission scanning electron microscope (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) analysis. The FESEM characterization revealed no impact of the wastes on either fiber diameter or the branching scheme, whereas the AFM depicted a BNC film with minimal roughness was generated using date wastes. Furthermore, a high crystallinity index was estimated by XRD up to 94% for the date wastes-derived BNC, while the FTIR analyses exhibited very similar profiles for all BNC films. Additionally, mechanical characteristics and water holding capacity of the produced Bncs were studied. Our findings substantiated that expensive substrates could be exchanged by agro-industrial wastes for Bnc production conserving its remarkable physical and microstructural properties. In the last decades, bacterial nanocellulose (BNC) has earned increasing global interest because of its remarkable physical and chemical properties, including green processing, low production costs, elevated mechanical properties, hydrophilicity, excellent biocompatibility, and biodegradability 1,2. Certain gram-negative non-pathogenic bacterial genera like Rhizobium, Xanthococcus, Pseudomonas, Azotobacter, Aerobacter, and Alcaligenes were reported to produce nanocellulose extracellularly, but the most common BNC-producing strains belong to the genus Komagataeibacter (formerly Acetobacter or commonly acetic acid bacteria) 1. Bacteria produce the BNC through a process of dual coupled steps: polymerization and crystallization. In the bacterial cytoplasm, glucose residues polymerize to β-1,4 glucan linear chains where they are extracellularly secreted. The developed chains are crystallized to microfibrils, then certain numbers of microfibrils consolidate to materialize highly pure 3D porous network of entangled nanoribbons of 20-60 nm in width 3 .

Considering the great impact of a material’s surface area on adsorption processes, hollow nanotube magnetic zinc oxide with a favorable surface area of 78.39 m2/g was fabricated with the assistance of microwave technology in the presence of poly vinyl alcohol (PVA) as a stabilizing agent followed by sonic precipitation of magnetite nano-particles. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs identified the nanotubes’ morphology in the synthesized material with an average aspect ratio of 3. X-ray diffraction (XRD) analysis verified the combination of magnetite material with the hexagonal wurtzite structure of ZnO in the prepared material. The immobilization of magnetite nanoparticles on to ZnO was confirmed using vibrating sample magnetometry (VSM). The sorption affinity of the synthesized magnetic ZnO nanotube for phenolic compounds from aqueous solutions was examined as a function of various processing factors. The degree of acidity of the phenolic solution has great influence on the phenol sorption process on to magnetic ZnO. The calculated value of ΔH0 designated the endothermic nature of the phenol uptake process on to the magnetic ZnO nanotubes. Mathematical modeling indicated a combination of physical and chemical adsorption mechanisms of phenolic compounds on to the fabricated magnetic ZnO nanotubes. The kinetic process correlated better with the second-order rate model compared to the first-order rate model. This result indicates the predominance of the chemical adsorption process of phenol on to magnetic ZnO nanotubes.

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Acrylonitrile-Styrene co-polymer was prepared by solution polymerization and fabricated into nanofibers using the electrospinning technique. The nanofiber polarization was enhanced through its surface functionalization with carboxylic acid groups by simple chemical modification. The carboxylic groups' presence was dedicated using the FT-IR technique. SEM showed that the nanofiber attains a uniform and porous structure. The equilibrium and kinetic behaviors of basic violet 14 dye sorption onto the nanofibers were examined. Both Langmuir and Temkin models are capable of expressing the dye sorption process at equilibrium. The intraparticle diffusion and Boyd kinetic models specified that the intraparticle diffusion step was the main decolorization rate controlling the process.

This work focuses mainly on environmental concern and protection through providing beneficial use of waste biomass from water hyacinth to produce economical nano-magnetic adsorbent material-efficient for facile oil spill separation via an external magnetic field. The water hyacinth roots showed higher oil spills adsorption affinity of 2.2 g/g compared with 1.2 g/g for shoots. Nano-activated carbon was successfully extracted from the roots of water hyacinth after alkaline activation and followed by zinc chloride treatment before its carbonization. Nano-magnetite was induced into the activated carbonized nanomaterials to synthesized nano-magnetic activated carbon hybrid material (NMAC). X-ray diffraction elucidated the crystalline nature of both extracted activated carbon from water hyacinth and its magnetic hybrid material. Scanning electron microscopic micrographs implied the nano-size of both prepared activated carbon and the magnetite hybrid materials. The magnetic properties of the fabricated nano-magnetic activated carbon were evaluated using the vibrating sample magnetometer. The magnetic nano-hybrid material recorded a maximum oil adsorption affinity of 30.2 g oil/g. The optimum oil spill of 80% was established after 60 min in the presence of 1 g/L of magnetic nano-hybrid. The magnetic nano-hybrid material that absorbs oil spills was separated from the treatment media easily using an external magnetic field. Shoreline and offshore waters can be contamiend by oil drilling, accidents including oil tankers, processes, runoffs from offshore oil explorations and productions. These oil spills have a harmful impact on human health, fauna and onnatural flora. Therefore, it is an essential issue to develop new technologies for remediation the spilled oil on water 1. Physical, chemical and biological processes can be used to remove the oil or to destroy it in-situ. These methods involve oil booms, dispersants, skimmers and sorbents. Most of these techniques are costly and ineffective for sorption oil trace level 2. Among the different available methods utilized for oil decontamination from a water surface, adsorption is considered one of the most prominent techniques for oil spillage treatment in the presence of ambient conditions. The oil sorbent materials can be classified as inorganic mineral materials, organic natural sorbents and organic synthetic sorbents. The most important characteristics of oil sorbent materials are their hydrophobicity, the surface area and the sorbent materials capillarity. Despite the organic oil sorbent materials characterized by most of these properties, however, they are non-biodegradable and non-environmentally friend. So, they are substituted by natural sorbents such as rice straw, cotton, peat moss, cotton grass, kapok and water hyacinth have been examined as ecofriendly sorbents for spilled oil. Besides, these agricultural-based materials are inexpensive. Some of these agricultural products are waste materials, so, their reuse will save waste disposal fee 3. Water hyacinths (Eichho...