This investigation aimed at evaluating the efficiency of micro and nanoclays as a low-cost material for the removal of crystal violet (CV) dye from an aqueous solution. The impacts of various factors (contact time, pH, adsorbent dosage, temperature, initial dye concentration) on the adsorption process have been taken into consideration. Six micro and nanoclay samples were obtained by treating clay materials collected from different locations in the Albaha region, Saudi Arabia. Out of the six tested micro and nanoclays materials, two (NCQ1 and NCQ3) were selected based on the highest adsorption efficiency for complete experimentation. The morphology and structure of the selected micro and nanoclay adsorbents were characterized by various techniques: SEM-EDX, FTIR, XRF, XRD, and ICP-MS. The XRF showed that the main oxides of both nanoclays were SiO₂, Al₂O₃, Fe₂O₃, K₂O, CaO, and MgO, and the rest were impurities. All the parameters affecting the adsorption of CV dye were optimized in a batch system, and the optimized working conditions were an equilibrium time of 120 min, a dose of 30 mg, a temperature of 25 °C, and an initial CV concentration of 400 mg/L. The equilibrium data were tested using nonlinear isotherm and kinetic models, which showed that the Freundlich isotherm and pseudo-second-order kinetics gave the best fit with the experimental data, indicating a physico-chemical interaction occurred between the CV dye and both selected micro and nanoclay surfaces. The maximum adsorption capacities of NCQ1 and NCQ3 adsorbents were 206.73 and 203.66 mg/g, respectively, at 25 °C. The thermodynamic factors revealed that the CV dye adsorption of both micro and nanoclays was spontaneous and showed an exothermic process. Therefore, the examined natural micro and nanoclays adsorbents are promising effective adsorbents for the elimination of CV dye from an aqueous environment.

The current research intended to employ a facile and economical process, which is also ecofriendly to transform camel waste bones into novel heterostructure for cleansing of diverse waste waters. The bones of camel were utilized for preparation of hydroxyapatite by hydrothermal method. The prepared hydroxyapatite was applied to the synthesis of cerium oxide-hydroxyapatite coated with natural polymer chitosan (CS-HAP-CeO₂) heterostructure. Being abundant natural polymer polysaccharide, chitosan possesses exceptional assets such as accessibility, economic price, hydrophilicity, biocompatibility as well as biodegradability, therefore style it as an outstanding adsorbent for removing colorant and other waste molecules form water. This heterostructure was characterized by various physicochemical processes such as XRD, SEM-EDX, TEM, and FT-IR. The CS-HAP-CeO₂ was screened for adsorption of various industrially important dyes, viz., Brilliant blue (BB), Congo red (CR), Crystal violet (CV), Methylene blue (MB), Methyl orange (MO), and Rhodamine B (RB) which are collective pollutants of industrial waste waters. The CS-HAP-CeO₂ demonstrated exceptional adsorption against CR dye. The adsorption/or removal efficiency ranges are BB (11.22%), CR (96%), CV (28.22%), MB (47.74%), MO (2.43%), and RB (58.89%) dyes. Moreover, this heterostructure showed excellent bacteriostatic potential for E. coli, that is liable for serious waterborne diseases. Interestingly, this work revealed that the incorporation of cerium oxide and chitosan into hydroxyapatite substantially strengthened antimicrobial and adsorption capabilities than those observed in virgin hydroxyapatite. Herein, we recycled the unwanted camel bones into a novel heterostructure, which assists to reduce water pollution, mainly caused by the dye industries.

Environmental pollution, especially water pollution caused by dyes, heavy metal ions and biological pathogens, is a root cause of various lethal diseases in human-beings and animals. Water purification materials and treatment methods are overpriced. Consequently, there is an imperative outlook observance for cheap materials for the purification of wastewaters. In order to fill up the projected demand for clean water, the present study aimed to make use of cost-effective and environmentally friendly methods to convert bone-waste from animals such as cows into novel composites for the decontamination of water. The bone-waste of slaughtered cows from the Najran region of Saudi Arabia was collected and used for the synthesis of hydroxyapatite based on the thermal method. The synthesized hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂) was utilized to prepare a manganese ferrite/hydroxyapatite composite. The nanocomposite was categorized by diverse sophisticated procedures, for instance XRD, FE-SEM, EDX, TEM, UV, PL and FT-IR. This composite possesses outstanding photocatalytic activity against methylene blue dye, which is a common pollutant from industrial wastes. Moreover, the synthesised composite revealed exceptional bacteriostatic commotion towards E. coli and S. aureus bacteria, which are accountable for acute waterborne infections. The outcome of this study demonstrated that the integration of manganese ferrite into hydroxyapatite significantly intensified both antimicrobial and photocatalytic actions when compared to the virgin hydroxyapatite.

Strontium titanate (SrTiO₃) and chromium doped SrTiO₃ (Cr/SrTiO₃) were prepared by modified sol–gel method with the citric acid as a chelating agent in the ethylene glycol solution for the effective photodegradation of methylene blue dye under visible light irradiation. The synthesized doped and un-doped SrTiO₃ nanoparticles were structurally characterized and their photoresponse performances for the efficient degradation of methylene blue dye have been demonstrated. After introducing the Cr on SrTiO₃, UV-Vis absorption was appeared the red-shift at 566 nm from 392 nm as compare with bare SrTiO₃. The photocatalytic degradation activity of Cr/SrTiO₃ was significantly improved to 60% degradation of methylene blue in 3 h under visible light, which is ∼5 times higher than that of the bare SrTiO₃.

Bacterial infections remain a serious and pervasive threat to human health. Bacterial antibiotic resistance, in particular, lowers treatment efficacy and increases mortality. The development of nanomaterials has made it possible to address issues in the biomedical, energy storage, and environmental fields. This paper reports the successful synthesis of CeO₂−SnO₂ composite nanofibers via an electrospinning method using polyacrylonitrile polymer. Scanning and transmission electron microscopy assessments showed that the average diameter of CeO₂−SnO₂ nanofibers was 170 nm. The result of photocatalytic degradation for methylene blue dye displayed enhanced efficiency of the CeO₂−SnO₂ composite. The addition of SnO₂ to CeO₂ resulted in the enhancement of the light absorption property and enriched charge transmission of photoinduced electron–hole duos, which conspicuously contributed to momentous photoactivity augmentation. Composite nanofibers exhibited higher specific capacitance which may be accredited to the synergism between CeO₂ and SnO₂ particles in nanofibers. Furthermore, antibacterial activity was screened against Escherichia coli and CeO₂−SnO₂ composite nanofibers depicted excellent activity. The findings of this work point to new possibilities as an electrode material in energy storage systems and as a visible-light-active photocatalyst for the purification of chemical and biological contaminants, which would substantially benefit environmental remediation processes.