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Industrial wastewater contains heavy metals, colors, dyes, cyanides, and natural manufactured compounds are expanding around the world. It prompts extreme water shortage just as water quality issues. With enhancing worldwide interest for clean and reestablish water for human utilization. Wastewater treatment with membrane innovation is arising as a main cycle to address the issues. In this current work, we have found the expulsion of dangerous metal particles utilizing a nano-ZnO (0.5 wt%) incorporated poly (ether ether sulfone) (PEES) nanofiltration membrane. The created membranes were reviewed by ATR-FTIR, AFM, SEM investigations, XRD, contact angle estimation, mechanical properties, pure water flux, porosity and molecular weight cut-off, arsenic, fluoride, and nitrate rejection studies were illustrated. Because of the hydrophilic nature of ZnO, the resultant membranes had better hydrophilicity than PEES membranes based on porosity, water content, surface chemistry, membrane morphology, and contact angle data. The Nano-ZnO incorporated membrane demonstrated a superior quality execution contrasted with neat PEES membrane. We discovered that the rejection of As(III) and As (V) were > 85% and > 98% separately, and an expanded permeability of 559.28 ± 2 Lm -2  h -1 and 297.95 ± 2 Lm -2  h -1 individually was seen at pH 10. Fluoride and nitrate particles additionally indicated the most extreme expulsion efficiencies were > 89% and > 75% separately. The prepared membrane samples were incubated in water (40 °C) and sodium hypochlorite solution (active chlorine concentration 400 mg/L) for up to 10 days to determine the stability of polymer membrane matrix. The general outcomes inferred that the nano-ZnO incorporated PEES membrane gave remarkable result to eliminate dangerous metal ions with moderate permeability., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Lignin from sugarcane bagasse was extracted using three different methods such as Alkaline, Ethanosolv, and Hydrotropic extraction and the effect of each method on yield and quality of bio-oil obtained when the lignin was depolymerized through solvothermal liquefaction was studied using ethanol as solvent. The maximum lignin yield was obtained in the hydrotropic extraction method when Sodium Xylene Sulfonate was used as the hydrotropic solvent at a concentration of 1.43 M and a temperature of 90 °C. Hydrothermal experiments were performed at temperature of 250 °C with a residence time of 30 min and lignin to ethanol ratio of 1:200 g/mL respectively. Among the methods used, the Ethanosolv lignin showed the highest extent of depolymerization (86.7%) to yield bio-oil at 250 °C with reduced biochar formation at lignin to solvent ratio of 1:200. Biochar obtained was used in adsorption studies of Cadmium (Cd), Lead (Pb), Nickel (Ni), and Zinc (Zn) and results showed that more than 85% removal of all the metals under lower concentration levels., (Copyright © 2021. Published by Elsevier Ltd.)

In the present study, fatty acid synthesis genes such as alpha and beta subunits of acetyl CoA carboxylase (accA and accD) were overexpressed in the glgC (Glucose-1-phosphate adenylyltransferase) knockout Synechocystis sp. PCC 6803. The biomass and lipid contents were evaluated in both the wild type and the engineered strains after copper treatment. The maximum lipid production of 0.981 g/L with the productivity of 81.75 mg/L/d was obtained from the copper treated ΔglgC + A-OX strain, which showed a 3.3-fold increase compared to the untreated wild type with satisfactory biodiesel properties. After copper treatment the knockout strain improved the unsaturated fatty acids level contributing to the increase of the saturated and mono-unsaturated ratio with improvement of the fuel quality. Copper induced oxidative stress also improved the photosynthetic pigments in engineered strains leading to increased tolerance against oxidative stress in the engineered strains. The copper treatment increased the antioxidant enzyme activities in the engineered strains especially in ΔglgC + A-OX strain. The carbon flux to lipid synthesis was enhanced by the engineered strains particularly with the knockout-overexpression strains. The Synechocystis sp. PCC 6803 engineered with ΔglgC + A-OX showed high potential for fuel production after the copper treatment., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A variety of rare earth metals (La, Sm, Nd, Ce, Gd) doped cadmium sulfide (RE-CdS) grafted reduced graphene oxide (G) sheet nanocomposites estimated imperative attention due to their visible light-driven, tunable band gap and high surface to volume ratio were investigated for the photocatalytic degradation of cationic dye from aqueous solution. The formation of wurtzite (hexagonal) crystal structures of cadmium sulfide nanoparticles (NPs) was confirmed by Powder X-ray diffraction spectra and the average crystallite size was determined to be 10 ± 2 nm. HRTEM analysis confirmed the homogeneous distribution of RE-CdS NPs over the G sheets. The photocatalytic behaviour of the RE-CdS decorated G sheets was studied using a textile dye methylene blue (MB) under sunlight. The result indicates that among the various RE-CdS nanocomposites studied, Cerium-cadmium sulfide-reduced graphene oxide (Ce-CdS-G) shows highest MB degradation of 99.0 ± 0.4% within 90 min under sunlight. The result confirms that RE-CdS-G nanocatalyst efficiently accelerates the separation and slows down the recombination rate in photo excited charge carriers. The catalytic activity was retained over 80% of its original value even after four successive runs and the present method can be employed for the large-scale synthesis of RE-CdS-G nanocatalyst., (Copyright © 2021. Published by Elsevier Ltd.)

This study involves the production of hydrocarbons from lignin extracted from sugarcane bagasse using Hydrothermal Liquefaction (HTL) followed by Hydrodeoxygenation (HDO). HTL of the lignin was studied under different solvents-methanol, ethanol and isopropanol in the presence of formic acid as an effective H-donor under varying lignin to solvent ratios (L:S = 1:15,1:30,1:40 g/mL), reaction temperatures (200 °C - 320 °C), reaction times (15, 30, 45,60 min) and ZnCl 2 catalyst concentrations (30, 40, 50, 60 wt%). A maximum of 86% lignin derived phenolics was obtained when ethanol was used as solvent at 250 °C under L:S = 1:30 at 30 min reaction time with 60 wt% ZnCl 2 . The lignin-oil was upgraded by HDO process in the presence of Ni/Al 2 O 3 catalyst and a maximum hydrocarbon yield of 73.5% was obtained with a HHV value of 48 MJ/kg. The hydrocarbons had excellent properties with a carbon range of C 6 -C 12 with a purity of 51.2%., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Hydrothermal liquefaction (HTL) of biomass results in the formation of bio-oil, aqueous phase (HTL-AP), bio-char, and gaseous products. Safer disposal of HTL-AP is difficult on an industrial scale since it comprises low molecular acid compounds. This review provides a comprehensive note on the recent articles published on the effective usage of HTL-AP for the recovery of valuable compounds. Thermo-chemical and biological processes are the preferred techniques for the recovery of biofuel, platform chemicals from HTL-AP. From this review, it was evident that the composition of HTL-AP and product recovery are the integrated pathways, which depend on each other. Substitute as reaction medium in HTL process, growth medium for algae and microbes are the most common mode of reuse and recycle of HTL-AP. Future research is needed to depict the mechanism of HTL process when HTL-AP is used as a reaction medium on an industrial scale. Need to find a solution for the hindrance in commercializing HTL process and recovery of value-added compounds from HTL-AP from lab scale to industry level. Integrated pathways on reuse and HTL-AP recycle helps in reduced environmental concerns and sustainable production of bio-products., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, seven different cyanobacteria (LS01-LS07) were isolated from paddy field water and among them, the isolate LS04 was able to grow well on municipal wastewater. The LS04 isolate was identified as Nostoc sp. (designated as Nostoc sp. LS04) based on 16S rRNA gene sequence analysis. Strain LS04 grew well in 75% wastewater and had the greatest nutrients removal efficiency (81.02-95.17%). Strain LS04 obtained the higher biomass (1.31 ± 0.08 g L -1 ) and productivity of 131.33 ± 8.08 mg L -1 d -1 . The lipid content and productivity of LS04 were 14.85 ± 0.86% (dry cell weight) and 19.46 ± 0.05 mg L -1 d -1 , respectively. The high proportion of C16-C18 fatty acids found in the lipids of LS04 indicated the high suitability for biodiesel production. In addition, Nostoc sp. LS04 cellular extracts were potentially used as a biostimulant for Lactuca sativa cultivation. The foliar application of 60% LS04 cellular extracts showed the maximum shoot length, root length, fresh biomass, dry biomass, Chl a, Chl b and carotenoids in lettuce plants compared to control plants. Similarly, 60% of LS04 cellular extracts treatment improved the concentrations of macro and micronutrients, and biochemical compounds in the leaves. Therefore, these results reveal that the Nostoc sp. LS04 is a promising candidate for the nutrients removal from wastewater and their biomass is a potential resource for biodiesel production and biostimulant for sustainable crop production., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, Chlorella sp., Scenedesmus sp., and their consortium were used for the biorefinery approach. The algal consortium (Chlorella sp. + Scenedesmus sp.) grown well in 75% diluted wastewater, and obtained the highest biomass (1.78 g L -1 ), chlorophyll (27.03 μg mL -1 ), protein (175 μg mL -1 ) and lipid content (34.83% dry cell weight). Algal consortium showed mainly 51.75% of palmitic acid and 35.45% of oleic acid in the lipids. The removal of nitrate, ammonium, phosphate, chemical oxygen demand, total organic carbon and total nitrogen in 75% diluted wastewater by algal consortium were 96%, 98%, 95%, 83%, 86% and 94%, respectively. Moreover, deoiled algal biomass (DAB) waste used as a biofertilizer combined with inorganic fertilizer resulted in the grater improvement of Solanum lycopersicum shoot length (44%), root length (89%), fresh weight (95%), dry weight (53%), macro and micro-nutrients (N 61%, P 179%, K 71%, Ca 38%, Mg 26% and Fe 11%), and tomato yield (174%) as compared to control treatment. Our results indicate that the use of consortium is not only a potential bioresource for wastewater treatment and biodiesel production but also the DAB waste is an effective biofertilizer for sustainable agriculture production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)