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Dewatered sludge (DS) is a sewage sludge with a unique property due to extracellular polymeric substances (EPSs) and polymer flocculants. These components form a stable 3D polymer network to increase dewatering efficiency, leaving behind valuable materials such as lipids. This article explored the influences of DS particle size on lipid yield and the effects of extraction on the chemical, morphological, and thermal properties of the residual dewatered sludge (RDS). Lipid yields with unimodal distribution were observed across the particle size ranges (<0.5, 0.5–1.0, 1.0–2.0, 2.0–4.0, and 4.0 mm). The highest lipid yield of 1.95% was extracted from 1.0–2.0 mm after 4 h at 70 °C and 0.1 g/mL sludge-to-solvent ratio. Efficiency was influenced by the DS's morphology, facilitating solvent infiltration and pore diffusion. The extraction process reduced water and organic fractions, resulting in higher thermal stability. Bibliometric analysis of "extraction*" and "sewage sludge" shows increasing research interest from 1973 to 2024. Five research clusters were observed: heavy metal speciation and stabilization, sludge and its bioavailability, extraction techniques and resource recovery, contaminants remediation, as well as phosphorus recovery and agricultural applications. These clusters highlight the diverse approaches to researching DS and RDS while promoting sustainable waste management. [ABSTRACT FROM AUTHOR]

Research into the speciation of sulfur and hydrogen molecules produced through the complex process of thermophilic dark fermentation has been conducted. Detailed surface studies of solid-gas systems using real biogas (biohydrogen) streams have unveiled the mechanisms and specific interactions between these gases and the physicochemical properties of a zeolite as an adsorbent. These findings highlight the potential of zeolites to effectively capture and interact with these molecules. In this study, the hydrogen sulphide removal analysis was conducted using 0.8 g of the adsorbent and at various reaction temperatures (25-125 °C), a flow rate of 100 mL min-1, and an initial concentration of approximately 5000 ppm hydrogen sulphide. The reaction temperature has been observed to be an essential parameter of Zeolite Socony Mobil - 5 adsorption capacity. The optimum adsorption capacity attains a maximum value of 0.00890 mg g-1 at an optimal temperature of 25 °C. The formation of sulphur species resulting from the hydrogen sulphide adsorption on the zeolite determines the kinetics, thermodynamics, and mass transfer behaviours of Zeolite Socony Mobil - 5 in hydrogen sulphide removal and Zeolite Socony Mobil - 5 is found to improve the quality of biohydrogen produced in thermophilic environments. Biohydrogen (raw gas) yield was enhanced from 2.48 mol H2 mol-1 hexose consumed before adsorption to 2.59 mol H2 mol-1 hexose consumed after adsorption at a temperature of 25 °C. The Avrami kinetic model was fitted for hydrogen sulphide removal on Zeolite Socony Mobil - 5. The process is explained well and fitted using the Temkin isotherm model and the investigation into thermodynamics reveals that the adsorption behaviour is exothermic and non-spontaneous. Furthermore, the gas molecule's freedom of movement becomes random. The adsorption phase is restricted by intraparticle diffusion followed by film diffusion during the transfer of hydrogen sulphide into the pores of Zeolite Socony Mobil - 5 prior to adsorption on its active sites. The utilisation of Zeolite Socony Mobil - 5 for hydrogen sulphide removal offers the benefit of reducing environmental contamination and exhibiting significant applications in industrial operations. [ABSTRACT FROM AUTHOR]

Hollow-fiber membranes for nanofiltration were prepared from the blending of Poly (ethylene glycol) (PEG) with Poly (vinyl chloride) (PVC) with different PEG molecular weights (400 and 4000 g/mol) and PVC via a dry/wet spinning process. In the spinning process, the effects of air gap, wind-up speed, dope extrusion rate, and bore extrusion rate were examined. In addition, the different lengths of the center tube, which acted as the inner-side fiber diameter during the preparation of hollow-fiber membranes, were studied. This research was investigated in order to observe the morphological, dielectric, and dynamic mechanical thermal properties to identify a suitable preparation of a hollow-fiber membrane for feasible applications. The morphology of the PVC-580 blended PEG-400 5 weight percent hollow-fiber membrane was seen to have a dense skin on both the inner and outer fiber surface, along with a suitable dope viscosity. Moreover, it offered finger-like substructures that could provide a high applicable feed-stream permeability and selectivity. Finger-like substructures were present on the near inner fiber surface at the controlled center-tube length of 0.3 cm, more so than at the center tube of 1 cm. This was because the solvent and non-solvent in the lumen tube exchanged more quickly than they did in the coagulant bath. The effect of the wind-up speed during the spinning process was significantly influenced by an affordable hollow fiber that can be indicated by the drawing ratio (λ). It was found that the drawing ratio of 3.3 showed a thickness thinner than 2.6 and 2.0, respectively. In summary, a controlled wind-up speed, an acceptable dope viscosity, and—most importantly—an agglomerated time resulted in membrane preparation. [ABSTRACT FROM AUTHOR]

Mycelium-based composites are a promising avenue for innovating sustainable materials from the hyphae of fungi. This study focuses on the use of fibers from four local fungal species, namely, Pleurotus ostreatus, Pleurotus sajor-caju (Fr. Singer), Auricularia auricula-judae, and Schizophyllum commune Fr., to produce mycelium-based composites from water hyacinth. An inoculum of each of the mushroom species was cultivated on PDA medium at 25 and 30 °C to determine the optimal temperature based on the growth rate. The obtained optimal condition was used to grow the fungi on water hyacinth (WH) mixed with rice bran in different proportions (100% WH, 70% WH, and 50% WH) with various numbers of fungal inocula (10, 20, and 30 plugs). The obtained composites were coated with a solution of either starch, chitosan, or epoxy resin. Schizophyllum commune Fr. exhibited the highest growth rate and fiber density, with a growth rate of 1.45 ± 1.92 mm/day at 30 °C. Ten inocula of Schizophyllum commune Fr. incubated at 30 °C for seven days on a mixture of 50% WH and 50% rice bran gave the optimal composite. Coating the obtained composite with chitosan improved its mechanical properties, but coating it with epoxy resin improved its water absorbency. Buried in soil, the composite coated with a chitosan solution decomposed within 30 days. The results indicate that Schizophyllum commune Fr. can be used as a binder to produce mycelial composites on a substrate of WH mixed with rice bran. The implications of these results will enable the further development and tuning of mushroom-based materials, especially for the production of sustainable bio-construction materials derived from local mushrooms and bio-waste. [ABSTRACT FROM AUTHOR]

The present study describes the removal of reactive black 5 (RB5) using sodium carboxymethyl cellulose (NaCMC)-stabilized ZnO nanocomposite (ZnO-NaCMC)-incorporated polymer membranes (PMs). Herein, PMs were fabricated using six different polymers, such as cellulose triacetate (CTA), polysulfone (PSF), polyvinylidene fluoride (PVDF), polyphenylsulfone (PPSU) and polyetherimide (PEI). The permeation experiments, hydrophilicity, porosity, mechanical stability and ultrafiltration performance for RB5 dye removal and dye adsorption capacity of the membranes were tested for the as-prepared PMs. Water permeation studies revealed that ZnO-NaCMC nanocomposite-embedded PMs exhibit higher flux than all pristine polymer membranes. The incorporation of the ZnO-NaCMC nanocomposite into the dope solution increased the hydrophilicity and adsorption capacity of the PMs. In addition, the mechanical strength of the PMs was also enhanced owing to the presence of the ZnO-NaCMC nanocomposite in the membrane. PPSU/ZnO-NaCMC and PEI/ZnO-NaCMC PMs showed good colour rejection and appreciable water flux compared to pristine PMs. Moreover, the anti-fouling properties of the PMs have also been enhanced by adding ZnO-NaCMC nanocomposites. [ABSTRACT FROM AUTHOR]

Polymeric membranes offer straightforward modification methods that make industry scaling affordable and easy; however, these materials are hydrophobic, prone to fouling, and vulnerable to extreme operating conditions. Various attempts were made in this study to fix the challenges in using polymeric membranes and create mixed-matrix membrane (MMMs) with improved properties and hydrophilicity by adding titanium dioxide (TiO2) and pore-forming agents to hydrophobic polyvinylidene fluoride (PVDF). The PVDF mixed-matrix ultrafiltration membranes in this study were made using the non-solvent phase inversion approach which is a simple and effective method for increasing the hydrophilic nature of membranes. Polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) as pore-forming chemicals were created. Pure water flux, BSA flux, and BSA rejection were calculated to evaluate the mixed-matrix membrane's efficiency. Bovine serum albumin (BSA) solution was employed in this study to examine the protein rejection ability. Increases in hydrophilicity, viscosity, and flux in pure water and BSA solution were achieved using PVP and PEG additives. The PVDF membrane's hydrophilicity was raised with the addition of TiO2, showing an increased contact angle to 71°. The results show that the PVDF–PVP–TiO2 membrane achieved its optimum water flux of 97 L/(m2h) while the PVDF–PEG–TiO2 membrane rejected BSA at a rate greater than 97%. The findings demonstrate that use of a support or additive improved filtration performance compared to a pristine polymeric membrane by increasing its hydrophilicity. [ABSTRACT FROM AUTHOR]

Across the globe, climate change is threatening the environment, crop yield and food security. The key to ensuring a sustainable environment, crop yield increase and food security is to identify the long-term significant impact of climate change and the means of reducing the effect. This study examined the impacts of climate change on cassava yield in Nigeria. Data were sourced from the Climate Change Knowledge Portal and the Food and Agricultural Organization of the United Nations spanning from 1990 to 2019. The impact of climate change was analyzed using Autoregressive Distributed Lag Bound approach, Error Correction Model and Augmented Dickey–Fuller and Phillips–Perron tests for stationarity test. The model was subjected to diagnostic tests such as stability tests, normality tests, serial correlation tests and heteroscedasticity tests. With the exception of temperature, the study revealed that arable land, rainfall and greenhouse gases such as C2O, nitrous oxide and methane had a long-term significant impact on cassava yield in Nigeria. The study also noted that methane causes long-term significant damage to cassava yield more than any other greenhouse gas and climatic variables in the study. We recommended policies and programs that facilitate the uptake of climate-smart agriculture that centers on greenhouse gas emission reduction and on crop improvement research by breeding crop varieties that will be resilient to climate shocks. [ABSTRACT FROM AUTHOR]

Correction for 'NaCMC-decorated ZnO nanocomposite polymer membranes for the separation of reactive dyes from textile water' by R. Robin et al., New J. Chem., 2023, 47, 20517–20526, https://doi.org/10.1039/D3NJ03783E. [ABSTRACT FROM AUTHOR]