Search Results (5)

Microbial contamination remains a global issue threatening human health. In this research, silver nanoparticles (AgNPs) were fabricated using Osmanthus fragrans flower extract as a reducing agent, and biochar derived from carbonizing waste barley distillers’ grain shells was used as a support to fabricate silver-loaded carbon (C-AgNP, C-Ag). PVA-CS-C-Ag-St gel was acquired by cross-linking polyvinyl alcohol (PVA), chitosan (CS), and starch (St) with glutaraldehyde (GA). Results from SEM, FTIR, and XRD demonstrated that PVA, CS, St, and C-Ag were successfully incorporated into the gel. The PVA-CS-C-Ag-S gel showcased excellent swelling and water retention properties, which had substantial antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, with inhibition zones of 25.0 mm, 22.5 mm, and 18.0 mm, respectively. Finally, the antimicrobial analysis revealed that PVA-CS-C-Ag-St gel exhibited excellent antimicrobial properties against typical Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Overall, the PVA-CS-C-Ag-St gel holds great promise for food preservation and environmental pollution control. Full article

Cadmium pollution is a serious environmental issue that has an impact on both the ecosystem and human health. As a result, its removal from water is essential. Agro-industrial wastes are suggested as a sustainable adsorbent option, as they are among the most readily available renewable sources worldwide. Biochar is a carbonized biomass that has been shown to be a viable and novel adsorbent. This article compares the results of cadmium adsorption on biochars derived from wood industry and craft beer production wastes. Biochars were characterized before and after adsorption. Batch adsorption results of 0.18 mmol/L Cd(II) concentration solutions indicated adsorption percentages (A%) of 99.7% and 92.2% for sawdust biochar and barley biochar, respectively. For this cadmium concentration, the sawdust biochar presented an adsorption capacity (q_m) of 0.0172 mmol/L, while the barley biochar presented a value of 0.0159 mmol/L. The influence of initial Cd(II) concentration on single and multimetal solutions was studied, and a decrease in Cd(II) adsorption on sawdust biochar was observed in the presence of Ni(II) and Zn(II). The Freundlich isotherm model was found to be the best fit to the data for Cd(II) adsorption isotherms on both biochars. According to the results of this article, sawdust biochar has the best performance as an adsorbent and can be safely disposed of in building bricks at the end of its useful life. Full article

To mitigate the environmental harm associated with high-input agriculture, arable farmers are increasingly required to maintain productivity while reducing inputs of synthetic fertilizers. Thus, a diverse range of organic products are now being investigated in terms of their value as alternative fertilizers and soil amendments. This study used a series of glasshouse trials to investigate the effects of an insect frass-based fertilizer derived from black soldier fly waste [HexaFrass™, Meath, Ireland] and biochar on four cereals grown in Ireland (barley, oats, triticale, spelt) as animal feed and for human consumption. In general, the application of low quantities of HexaFrass™ resulted in significant increases in shoot growth in all four cereal species, along with increased foliage concentrations of NPK and SPAD levels (a measure of chlorophyll density). These positive effects of HexaFrass™ on shoot growth were observed, however, only when a potting mix with low basal nutrients was used. Additionally, excessive application of HexaFrass™ resulted in reduced shoot growth and, in some cases, seedling mortality. The application of finely ground or crushed biochar produced from four different feedstocks (Ulex, Juncus, woodchip, olive stone) had no consistent positive or negative effects on cereal shoot growth. Overall, our results indicate that insect frass-based fertilizers have good potential in low-input, organic, or regenerative cereal production systems. Based on our results, biochar appears to have less potential as a plant growth promoting product, but could be used as a tool for lowering whole-farm carbon budgets by providing a simplistic means of storing carbon in farm soils. Full article

Agricultural waste can have a catastrophic impact on climate change, as it contributes significantly to greenhouse gas (GHG) emissions if not managed sustainably. Swine-digestate-manure-derived biochar may be one sustainable way to manage waste and tackle GHG emissions in temperate climatic conditions. The purpose of this study was to ascertain how such biochar could be used to reduce soil GHG emissions. Spring barley (Hordeum vulgare L.) and pea crops in 2020 and 2021, respectively, were treated with 25 t ha⁻¹ of swine-digestate-manure-derived biochar (B₁) and 120 kg ha⁻¹ (N₁) and 160 kg ha⁻¹ (N₂) of synthetic nitrogen fertilizer (ammonium nitrate). Biochar with or without nitrogen fertilizer substantially lowered GHG emissions compared to the control treatment (without any treatment) or treatments without biochar application. Carbon dioxide (CO₂), nitrous oxide (N₂O), and methane (CH₄) emissions were directly measured using static chamber technology. Cumulative emissions and global warming potential (GWP) followed the same trend and were significantly lowered in biochar-treated soils. The influences of soil and environmental parameters on GHG emissions were, therefore, investigated. A positive correlation was found between both moisture and temperature and GHG emissions. Thus, biochar made from swine digestate manure may be an effective organic amendment to reduce GHG emissions and address climate change challenges. Full article

Energy consumption is rising dramatically at the price of depleting fossil fuel supplies and rising greenhouse gas emissions. To resolve this crisis, barley waste, which is hazardous for the environment and landfill, was studied through thermochemical characterization and pyrolysis to use it as a feedstock as a source of renewable energy. According to proximate analysis, the concentrations of ash, volatile matter, fixed carbon, and moisture were 5.43%, 73.41%, 18.15%, and 3.01%, consecutively. The ultimate analysis revealed that the composition included an acceptable H/C, O/C, and (N+O)/C atomic ratio, with the carbon, hydrogen, nitrogen, sulfur, and oxygen amounts being 46.04%, 6.84%, 3.895%, and 0.91%, respectively. The higher and lower heating values of 20.06 MJ/kg and 18.44 MJ/kg correspondingly demonstrate the appropriateness and promise for the generation of biofuel effectively. The results of the morphological study of biomass are promising for renewable energy sources. Using Fourier transform infrared spectroscopy, the main link between carbon, hydrogen, and oxygen was discovered, which is also important for bioenergy production. The maximum degradation rate was found by thermogravimetric analysis and derivative thermogravimetry to be 4.27% per minute for pyrolysis conditions at a temperature of 366 °C and 5.41% per minute for combustion conditions at a temperature of 298 °C. The maximum yields of biochar (38.57%), bio-oil (36.79%), and syngas (40.14%) in the pyrolysis procedure were obtained at 400, 500, and 600 °C, respectively. With the basic characterization and pyrolysis yields of the raw materials, it can be concluded that barley waste can be a valuable source of renewable energy. Further analysis of the pyrolyzed products is recommended to apply in the specific energy fields. Full article