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Radioactive cesium ion (Cs-137) removal from wastewater was investigated by novel composite adsorbents, chitosan-bone powder (CS-KT) and chitosan-bone powder-iron oxide (CS-KT-M) at 25 and 50 °C. The characterization of adsorbents was performed by Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Brunauer-Emmett-Teller and Barrett-Joyner-Hallenda (BET-BJH), and Atomic Force Microscopy (AFM) analyses. While BET surface areas of CS-KT and CS-KT-M adsorbents were found to be 131.5 and 144.9 m2/g, respectively, average pore size and pore volume values were 4.69 nm/0.154 cm3/g and 7.49 nm/0.271 cm3/g, respectively. Amongst Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) models, Langmuir model fits well for Cs+ ion sorption by these adsorbents. The maximum adsorption capacity obtained from Langmuir adsorption isotherm was 0.98 × 10-4 mol/g at 25 °C, and 1.16 × 10-4 mol/g at 50 °C for CS-KT; it was found to be 1.79 × 10-4 mol/g at 25 °C and 2.24 × 10-4 mol/g at 50 °C for CS-KT-M. FT-IR analyses showed that Cs+ sorption occurs by its interaction with CO32-, PO43- and -NH2 groups. The average adsorption energy "E" was calculated as ca.11 kJ/mol from D-R adsorption isotherm. The adsorption kinetics was interpreted well by pseudo-second order model.Yak dung is used as fuel in Tibetan homes; however, this use is hazardous to health. An alternative use of the dung that would be profitable and offset the loss as a fuel would be very beneficial. Sweet sorghum silage with yak dung biochar as an additive was compared with a control silage with no additives and three silages with different commercial additives, namely Lactobacillus buchneri, Lactobacillus plantarum and Acremonium cellulase. Biochar-treated silage had a significantly greater concentration of water-soluble carbohydrates than the other silages (76 vs 12.4-45.8 g/kg DM) and a greater crude protein content (75.5 vs 61.4 g/kg DM), lactic acid concentration (40.7 vs 27.7 g/kg DM) and gross energy yield (17.8 vs 17.4 MJ/kg) than the control silage. HSP phosphorylation Biochar-treated and control silages did not differ in in vitro digestibility and in total gas (507 vs 511 L/kg DM) and methane production (57.9 vs 57.1 L/kg DM). Biochar inhibited degradation of protein and water-soluble carbohydrates and enhanced lactic acid production, which improved storability of feed. It was concluded that yak dung biochar is an efficient, cost-effective ensiling additive. The profit could offset the loss of dung as fuel and improve the health of Tibetan people.Great attention has been paid to using biochar as soil conditioner and bio-accumulator. Nevertheless, biochar application in agriculture might cause a potential hazard to ecosystems, considering that toxic organic pollutants present in biochar may enter the environment. European Biochar Certificate (EBC) set certain criteria for biochar production. Achieving the EBC established values of the molar ratio of H/Corg  0.1, inhibition of Sinapis alba less then 30% was observed with OC/EC  less then  0.02. To achieve Sinapis alba inhibition less then 20%, these parameters should be met volatile matter (VM) less then 30%; concentration of OC  less then  4%; aromaticity ratio AL/AR  less then  0.35.The increase of emerging contaminants, such as surfactants, is one of the major challenges to biological wastewater treatment. However, the potential impact of linear alkylbenzene sulphonates (LAS), a major class of anionic surfactants, on anammox process is unclear. The long-term effects of sodium dodecyl benzene sulfonate (SDBS, as a model LAS) on reactor performance, microbial community and sludge properties were investigated in this study. The presence of 5 mg L-1 SDBS promoted the release of extracellular microbial products from anammox granules and the wash-out of anammox population via effluent. Despite sludge disaggregation, the reactor performance was robust to the exposure of 5 mg L-1 SDBS due to functional redundancy. With the further increase of SDBS to 10 mg L-1, the metabolic activity of anammox biomass and the transcription and post-translation of hydrazine dehydrogenase were significantly decreased. The potential mechanism might be associated with the damage on cell membrane that induced the leakage of intracellular matrix. These results highlight the need to consider the potential risk of LAS to operation of anammox process in biological wastewater treatment plant.Nanoscale zero-valent iron (NZVI) and NZVI supported onto montmorillonite (NZVI-Mt) were synthetized and used in this study to remove SeVI and AsV from water in mono- and binary-adsorbate systems. The adsorption kinetics and isotherm data for SeVI and AsV were adequately described by the pseudo-second-order (PSO) (r2>0.94) and Freundlich (r2>0.93) equations. Results from scanning electron microscopy showed that the dimension of the NZVI immobilized on the Mt was smaller than pure NZVI. Using 0.05 g of adsorbent and an initial 200 mg L-1 AsV and SeVI concentration, the maximum adsorption capacity (qmax) and partition coefficient (PC) for AsV on NZVI-Mt in monocomponent system were 54.75 mg g-1 and 0.065 mg g-1·μM-1, which dropped respectively to 49.91 mg g-1 and 0.055 mg g-1·μM-1 under competitive system. For SeVI adsorption on NZVI-Mt in monocomponent system, qmax and PC were 28.63 mg g-1 and 0.024 mg g-1·μM-1, respectively. Values of qmax and PC were higher for NZVI-Mt than NZVI and montmorillonite, indicating that the nanocomposite contained greater adsorption sites for removing both oxyanions, but with a marked preference for AsV. Future research should evaluate the effect of different operational variables on the removal efficiency of both oxyanions by NZVI-Mt.Certainly water pollution control will play a key role in environmental health. Therefore, researchers are attempting to reduce the ecological effects of water pollution by creating restrictions in the use of chemicals or water reuse. Among all the available techniques, adsorption method attracted much attention due to the higher efficiency, cost-effectiveness and simplicity. So, in this work, novel biodegradable hydrogel based on carboxymethyl cellulose (CMC) and polyaniline (PANI) was introduced to remove toxic dyes from wastewater. The synthesis process was accomplished in two steps free radical polymerization of acrylic acid (AA) on the CMC (0.25 g) in the presence of ammonium per sulfate (APS) as radical initiator (0.2 g) and N,N-methylene-bis-acrylamide (MBA) as crosslinker (0.1 g) at 70 °C, and after 30 min, growing PANI chains on the synthesized CMC-PAA hydrogel by radical polymerization of aniline (1.0 mL) in acidic condition (20 mL of hydrochloric acid 1.0 M) to form macro-porous conductive hydrogel (CMC-PAA-PANI).

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