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Lithium-ion battery recycling includes discharging and processing exhausted batteries to recover valuable metals for reuse in new battery production. The improper disposal of e-waste draws attention to the possibility of reprocessing used lithium-ion batteries to make progress in recovering valuable metals. In this study, using biodegradable mixed organic acids, valuable metals were extracted from used batteries by a hydrometallurgical process under optimal conditions such as a stirring speed of 200 rpm, mixed acid concentration of ascorbic acid/citric acid (AA/CA) of 50:50 mM, temperature of 50 °C, time of 50 min, and slurry density of 20 g/L. Kinetic studies verified that the apparent activation energies, 43.6, 70.5, 49.8, 60.6, 45, and 6 kJ/mol, and surface chemical reactions controlled the leaching process for Li, Mn, Co, Ni, and Cu from cathode powder obtained from used LIBs. XRD and FT-IR confirmed the crystalline nature of the cathode powder. UV–visible spectra showed a Co(II) complex with λmax at 380 nm by reduction of the Co(III) complex. Lithium was recovered by LiF and as MnO2 using ammonium persulfate. Our efforts aimed to recover it through an economical and environmentally friendly approach. [ABSTRACT FROM AUTHOR]

New PVC/ABS and CoCl2 composites with various concentrations of cobalt chloride (≤10 wt. %) were synthesized by solution casting techniques and investigated by spectro-chemical, morphological and thermal mode of characterization. The FT-IR, XRD and SEM analyses proved the smooth distribution and uniformity of the constituents of the composite materials. Thermal behavior showed that the addition of CoCl2 to the PVC/ABS blends enhanced the thermal stability and improved mechanical properties of composites due to crosslinking between PVC/ABS blend and CoCl2. Thus based on their remarkable morphology, thermomechanical stability and promising bioactivities, the synthesized composites could be applied for high performance polymeric materials in the field of biomedics and electronics.

Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H2O2) and pH conditions were evaluated. The λmax of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a significant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no influence on degradation efficiency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.

Aqueous pollution due to textile industry is an important issue. Photocatalysis is one of the methods used for eradication of dyes from textile industrial effluents. In this study, the synthesis, characterization and evaluation of photo catalytic activity of Ag-TiO2 is reported. TiO2 catalysts with 2, 4, 6 and 8% loading of Ag were prepared by green methods using Azadirachta indica leaves extract as reducing agent with titanium dioxide and silver nitrate as precursor materials. Prepared catalyst was characterized by advanced techniques and was used as catalyst for degradation of Methylene blue and Rhodamine B dyes. Deposition of Ag greatly enhanced the catalytic efficiency of TiO2 towards degradation of dyes. Irradiation of catalyst excites electrons from conduction band of catalyst to valence band yielding an electron-hole pair. This electron-hole pair undergoes secondary reactions and produce OH∙ radicals. These active radicals take part in degradation of dyes. More than 90% dyes were degraded in 120 min. Photo catalytic degradation of Methylene blue and Rhodamine B followed Eley-Rideal mechanism which states that dye react in fluid phase with adsorbed oxygen.

The paper emphases on the removal of Reactive Blue 194 dye (RB-194) using different process variables alone and in combination as well. A Cs-137 γ-radiation source was used to treat RB-194 at a dose rate of 669 Gy/h (Gray/h) with 1-10 kGy irradiation dose in the presence of (0.2-0.6 mL) hydrogen peroxide. The optimization of various process variables such as pH, γ-radiations absorbed dose, initial concentration of RB-194 and concentration of H2O2 were done to achieve thoroughgoing degradation. The dye was considerably degraded (79%) by γ-radiation but the addition of 0.6 mL H2O2 increased the degradation to 97% at a 10 kGy irradiation dose in acidic pH. The Fourier-transform infrared spectroscopy technique confirmed the presence of various useful groups. The fragmented by-products of RB-194 produced by irradiation at a 10 kGy dose were identified by liquid chromatography-mass spectrometry. The results revealed that dye molecules are degraded after decolorization to lower molecular weight substances, primarily organic acids, and carbon dioxide. The findings demonstrated that RB-194 could be efficiently removed from wastewater using γ-radiations along H2O2. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HNTs) reinforced epoxy composites with improved mechanical properties were prepared. The prepared HNTs reinforced epoxy composites demonstrated improved mechanical properties especially the fracture toughness and flexural strength. The flexural modulus of nanocomposite with 6% mHNTs loading was 11.8% higher than that of neat epoxy resin. In addition, the nanocomposites showed improved dimensional stability. The prepared halloysite reinforced epoxy composites were characterized by thermal gravimetric analysis (TGA). The improved properties are attributed to the unique characteristics of HNTs, uniform dispersion of reinforcement and interfacial coupling.

New PVC/ABS and CoCl2 composites with various concentrations of cobalt chloride (≤10 wt. %) were synthesized by solution casting techniques and investigated by spectro-chemical, morphological and thermal mode of characterization. The FT-IR, XRD and SEM analyses proved the smooth distribution and uniformity of the constituents of the composite materials. Thermal behavior showed that the addition of CoCl2 to the PVC/ABS blends enhanced the thermal stability and improved mechanical properties of composites due to crosslinking between PVC/ABS blend and CoCl2 . Thus based on their remarkable morphology, thermomechanical stability and promising bioactivities, the synthesized composites could be applied for high performance polymeric materials in the field of biomedics and electronics. [ABSTRACT FROM AUTHOR]

Nowadays, cobalt containing cathodes are widely used in solid oxide fuel cells (SOFCs) due to their high performance. There are many disadvantages of cobalt based cathodes such as reduction, high cost and evaporation of cobalt. In order to reduce these detrimental effects, cobalt free composites such as La0.54Sr0.46Zn0.20Fe0.80O3−δ (LaSrZnFeO1) La0.80Sr0.20Zn0.20Fe0.80O3−δ (LaSrZnFeO2), and La0.80Sr0.20Zn0.40Fe0.60O3−δ (LaSrZnFeO3) have been prepared by the sol–gel technique. The electrical properties and microstructure of the proposed cathode materials were investigated in this study. The characterization of the prepared materials was carried out by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The thermal stability of the synthesized materials was observed with thermogravimetric analysis (TGA). The highest DC conductivity of LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 cathodes achieved was 8.12, 7.12 and 6.62 S cm−1 at 600 °C, respectively. The single cell achieved maximum power densities of 436, 370 and 296 mW cm−2 with LaSrZnFeO1, LaSrZnFeO2, and LaSrZnFeO3 cathodes at 600 °C, respectively. The better current densities of 1472, 1422 and 1397 mA cm−2 for LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 were attained at 600 °C, respectively. The SEM images disclosed that the prepared nanocomposite cathodes were porous and homogeneous. The purity of the prepared samples was confirmed by XRD. The proposed LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 cathodes achieved a maximum OCV of 0.90, 0.83 and 0.76 volts at 600 °C, respectively. [ABSTRACT FROM AUTHOR]

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In this study, PMMA/ABS/CoCl2 ternary composite films were fabricated by the solution casting technique. The different weight ratios of cobalt chloride (≤10 wt) were incorporated into the PMMA/ABS blend (80:20). The chemical structure and thermal properties of the synthesized composites were assessed by FT-IR, TGA, and XRD. The biological properties of ternary composites, such as in vitro antibacterial activity and antioxidant capacity, were investigated. The enhanced thermal stability and promising antibacterial, selective antibiofilm, and potential antioxidant properties of PMMA/ABS/cobalt chloride composites demonstrated that they can be used for high-quality plastics and in many pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) have emerged as a promising approach for the removal of organic dyes from effluents. Different AOPs were employed for the degradation of Reactive Yellow 160A (RY-160A) dye, i.e., SnO2/UV/H2O2 and TiO2/UV/H2O2. In the case of UV treatment, maximum degradation of 28% was observed, while UV/H2O2 furnished 77.78% degradation, and UV/H2O2/TiO2 degraded the RY-160A dye up to 90.40% (RY-160A 30 mg/L, 0.8 mL of H2O2). The dye degradation was 82.66% in the case of UV/H2O2/SnO2 at pH 3. FTIR and LC-MS analyses were performed in order to monitor the degradation by-products. The cytotoxicity and mutagenicity of RY-160A dye were evaluated by hemolytic and Ames (TA98 and TA100 strains) assays. It was observed that the RY-160A dye solution was toxic before treatment, and toxicity was reduced significantly after treatment. Results indicated that UV/H2O2/TiO2 is more efficient at degrading RY-160A versus other AOPs, which have potential application for the remediation of dyes in textile effluents. [ABSTRACT FROM AUTHOR]

The PMMA/PVC/ZnO-nanocomposites with zinc oxide nanoparticle (particle size < 50nm) was synthesized by solution casting technique. Morphology of the synthesized nano composites have been investigated by FT-IR and XRD techniques. After characterization, synthesized composites were applied for antibacterial, selective antibiofilm and free radical scavenging screening. Antibacterial studies were measured against different bacterial strains. Antibiofilms activities were studied against those bacterial model pathogenic strains which showed highest and minimum sensitivity as a (~94 and ~88 at 160 µg/ml). Antioxidant activity of synthesized nanocomposites were measured by DPPH and showed scavenging capacity with IC50, 110 to > 200 µg/mL. Thus PMMA/PVC/ZnO nanocomposite showed promising antimicrobial activity and antioxidant activity that can be used for biomedical applications. [ABSTRACT FROM AUTHOR]

The hydro­thermal synthesis and crystal structure of the title two-dimensional coordination polymer, poly[bis­(μ3-3,4-di­amino­benzoato-κ³N³,O,O′)manganese(II)], [Mn(C7H7N2O2)2]n, are described. The Mn2+ cation (site symmetry \overline{1}) adopts a tetra­gonally elongated trans-MnN2O4 octa­hedral coordination geometry and the μ3-N,O,O′ ligand (bonding from both carboxyl­ate O atoms and the meta-N atom) links the metal ions into infinite (10\overline{1}) layers. The packing is consolidated by intra-layer N—H...O and inter-layer N—H...N hydrogen bonds. The structure of the title compound is compared with other complexes containing the C7H7N2O2− anion and those of the related M(C8H8NO2)2 (M = Mn, Co, Ni, Zn) family, where C8H8NO2− is the 3-amino-4-methyl­benzoate anion. [ABSTRACT FROM AUTHOR]