Issue 1

In this study, the basic fusion dye was adsorbed from wastewater using turmeric leaf waste biochar and the experimental outcomes were fitted with isotherm and kinetics. Further, Response Surface Methodology (RSM) was also performed to analyse the concurrent interactive effects of the process variables. Pyrolysis of turmeric leaf waste biomass resulted in biochar yield of 44.65% at temperature of 300 °C. The biochar had moisture content of 4.21%, volatile matter of 45.38%, ash content of 17.74% and fixed carbon of 32.65% respectively. The batch adsorption studies showed maximum dye removal of 87.44 % and 71% at temperature of 35 °C, dosage of 0.3g, time of 60 min, pH of 7 and dye concentration of 50 ppm respectively for biochar and biomass respectively. The experimental data obtained at equilibrium condition fitted well in pseudo-second order and Langmuir isotherm with R2 value of 0.98 respectively. This study provides base for usage of turmeric leaf-based waste for synthesis of biochar and for effective removal of dye from aqueous environment.

This research focuses on hydrothermal gasification (HTG) and hydrothermal liquefaction (HTL) studies to produce bio-hydrogen from domestic mixed waste. HTG and HTL studies were studied at temperatures of 300–450°C and 300–400°C, correspondingly, with a catalyst level of 6 wt %. The sol-gel technique was used to make the Bentonite/Nb-TiO2 catalyst. For a solvent-waste proportion of 14 millilitre/gram, an C2H5OH - water proportions of 2:2, and a period of one-hour, maximum H2 output from HTL was 30 wt % (catalyst loads: 4 wt %) and HTG was 40 wt % (catalyst loads: 5 wt %). As C2H5OH acts as half-solvent and ideal solvent to bio-mass capacity it shot up H2 result in the HTG procedure by methanation, gas water shift and improving responses in the organization. The second output of the HTL procedure was bio-oil, which yielded 35 wt % with O/C as well as H/C standards of 1.2 and 1.0, respectively, and an HHV of 42 Mega Joule/kilogram. In the HTL system, mechanistic procedures such depolymerization, hydration, reduction, and hydrolysis generated in a larger proportion of gaseous product. Thermal and the solvent-to-waste proportion is the ideal factors in the H2 synthesis procedure, according to experimental analysis. Energy nexuses from domestic mixed trash are taken over in this research.

The coconut shell-derived biochar was employed in this study to remediate Remazol Black B from aqueous solutions. For efficient dye remediation, preliminary batch investigations focused on adjusting temperature, biochar dosage, initial dye concentration, and pH. The results shown that dosage of biochar had a considerable effect on the potential of dye absorption, with 1 g/L performing well. In addition, the data revealed that a pH of 2.0 was employed to attain equilibrium. Different temperature ranges from 30°C to 45°C were used to explore the influence of temperature, with 35°C being found to be the optimal value. The characteristics of biochar were investigated using Fourier Transform Infrared Spectroscopy, thermogravimetric analysis, and a Scanning Electron Microscope. In addition, the potential of biochar desorption was investigated by varying the solid to liquid ratio for different elutants. Adsorption and kinetic study revealed that the adsorption was favoured by physical adsorption. According to the findings, it was found coconut shell-derived biochar can treat dye-bearing aqueous solutions with a removal efficiency of 69.67%.

Dewatered sludge is the main by-product from wastewater treatment and it contains various types of hazardous substances which can cause environmental pollution. The alternative utilization of sludge waste is for covering the landfill or as liner for the landfill. Landfill cover is a critical component to protect the surrounding environment from leachate contamination produced by landfills and it has specific characteristics. This study analyzes the optimum water content, permeability coefficient, and stability of the material consisting of a mixture of dewatered sludge, bentonite, and quicklime. The test results show that the optimum water content in the three composite variables meet the requirements; the highest optimum value was 28%, a mixture with a ratio of 84% sludge, 15% bentonite, and 1% quicklime. The results also show that mixing sewage sludge with bentonite significantly reduces the permeability value with a ratio of 80% sludge, and 20% bentonite produces the lowest permeability coefficient of 1.979 x 10-7 and this has reached the hydraulic conductivity limit of 1 x 10-7. The shear strength and safety factor results test show that V3 had the best results, with a cohesion value of 22.40 kPa, a shear angle of 31.97°, and a safety factor of 5.297. The addition of bentonite tends to reduce the value of the safety factor. This safety factor can reach a high value because of the ratio of the total shear resistance to the working soil shear stress.