Showing papers on "Sawdust published in 2022"

Adsorption of copper and nickel by using sawdust chitosan nanocomposite beads – A kinetic and thermodynamic study

Abstract: The adsorption behavior of biomaterial activated Sawdust-Chitosan nanocomposite beads (SDNCB) powder was investigated along with synthesis and experimental techniques approaches to study the removal efficiency of some heavy metal ions including Ni (II) and Cu (II) ions from aqueous solutions by assessing the surface-modified activated carbon by the cost-effective non-conventional method. Structural analysis of the entitled compound was evaluated by the PXRD techniques and its surface morphology was inferred by the following techniques: TEM, EDAX. The behavior of the functional group presents in the compound was discussed using the FTIR technique. Such parameters like dosage, pH, time, temperature, and initial concentration of copper and nickel were associated with this to examine the effect of adsorption of heavy elements that exist in the portable solution. Further, the cellulose and chitosan beads complex material have an appropriate surface area, it demonstrated metal ions removal efficiency was more appreciable due to the action of activated carbon, where this showed fast rate sorption kinetics due to strong involvement of Cu+ & Ni+ towards cellulose and chitosan's functional groups in the bio composite. The isotherm model so-called Langmuir, Freundlich, and Temkin model was utilized to plot the experimental adsorption dataset to infer the maximum adsorption capacity. Based on this model, the adsorption properties of the beads treated compound was determined by plotting the graphs in which sorption intensity (n) which implies expected sorption, and the correlation value are 1.989, 0.998, and 0,981 respectively.

Investigation of biochar from Cedrella fissilis applied to the adsorption of atrazine herbicide from an aqueous medium

Abstract: Biochar was produced from the sawdust of the wood forest species Cedrella fissilis and later used as an adsorbent to remove atrazine herbicide from aqueous media. Biochar showed high thermal stability, an amorphous structure, and a highly irregular surface, mainly composed of carbon-containing bonds. The isothermal curves confirmed that the increase in temperature favored the adsorption of the herbicide. The Langmuir model best suited the experimental equilibrium data, with the maximum adsorption capacity of 7.68 mg g-1 at 328 K. The thermodynamic parameters confirmed a spontaneous process of an endothermic nature governed by physical interactions (interactions of van der Waals and hydrogen bonds). Kinetic studies showed that equilibrium was reached within 180 min. The linear driving force model (LDF) showed good statistical adjustment to the experimental data, where it was observed that the diffusion coefficient increased with the concentration of adsorbate. Biochar can be reused in up to three cycles. Finally, the adsorbent showed good efficiency in real water samples from rivers contaminated with atrazine, with 76.58% and 71.29% removal.

Low-cost treated lignocellulosic biomass waste supported with FeCl3/Zn(NO3)2 for water decolorization

Abstract: Abstract Dye pollution has always been a serious concern globally, threatening the lives of humans and the ecosystem. In the current study, treated lignocellulosic biomass waste supported with FeCl 3 /Zn(NO 3 ) 2 was utilized as an effective composite for removing Reactive Orange 16 (RO16). SEM/EDAX, FTIR, and XRD analyses exhibited that the prepared material was successfully synthesized. The removal efficiency of 99.1% was found at an equilibrium time of 110 min and dye concentration of 5 mg L −1 Adsorbent mass of 30 mg resulted in the maximum dye elimination, and the efficiency of the process decreased by increasing the temperature from 25 to 40 °C. The effect of pH revealed that optimum pH was occurred at acidic media, having the maximum dye removal of greater than 90%. The kinetic and isotherm models revealed that RO16 elimination followed pseudo-second-order (R 2 = 0.9982) and Freundlich (R 2 = 0.9758) assumptions. Surprisingly, the performance of modified sawdust was 15.5 times better than the raw sawdust for the dye removal. In conclusion, lignocellulosic sawdust-Fe/Zn composite is promising for dye removal.

Vacuum Pyrolysis of Pine Sawdust to Recover Spent Lithium Ion Batteries: The Synergistic Effect of Carbothermic Reduction and Pyrolysis Gas Reduction

Abstract: Minimizing the energy consumption and expanding the usage of renewable material in the recovery of spent lithium ion batteries (LIBs) are significant for exploring more sustainable recycling approaches. Herein, we report a biomass carbothermic reduction approach to selectively recycle Li and Co from spent LIBs at a low temperature of 673 K. Pine sawdust (PS) was selected as the sample to provide reducing gas and carbon during the pyrolysis. During the reduction process, the PS-derived reducing gas and charcoal codrove the conversion of LiCoO2 to Co/CoO and Li2CO3, and over 94% of Li and 97% of Co were recovered. The synergistic effect of carbon and reducing gas is key to achieving the transformation process at a lower temperature than the common carbothermic reduction. Economic and environmental analysis based on the EverBatt model shows that this strategy reduces energy consumption and greenhouse gas (GHG) emissions, thereby increasing potential profit. Overall, this paper provides a green method to recycle spent LIBs via waste biomass with minimized secondary wastes.

Investigating the characterization, kinetic mechanism, and thermodynamic behaviour of coal-biomass blends in co-pyrolysis process

Abstract: The integration of biomass into existing thermochemical conversion processes for bioenergy production is expected to play a key role in the energy transition to reduce the reliance on depleting fossil fuels and mitigate fossil carbon emissions . In this study coal-biomass blends containing hemp and sawdust were prepared with various blending ratios for co-pyrolysis. The coal-biomass blends were characterised using ultimate analysis (CHN), gross calorific value (GCV), FTIR , and TGA . Co-pyrolysis was performed in TGA that was applied to study the thermokinetic behaviour of the respective blends. The deviation between the experimental and calculated values of TGA mass loss (ML), the residue left (RL), and maximum mass loss rate (DTG max ) were calculated to observe the synergistic effect . The positive deviation in the ML and DTG max values indicated the presence of a synergistic effect during co-pyrolysis. Kinetic parameters were analysed by employing the Coats-Redfern method with thirteen integral functions. The activation energy (E a ) for individual coal was 39 kJ/mol through a one and a half chemical reaction (F3/2), while individual sawdust and hemp showed 60 kJ/mol through a deceleratory reaction mechanism for contracting sphere (R3) and 44 kJ/mol through the second-order chemical reaction (F2), respectively. Thermodynamic parameters such as the change in enthalpy (ΔH) and change in Gibbs free energy (ΔG) showed positive values that indicate the reaction was non-spontaneous. Additionally, the change in entropy (ΔS) was negative that suggested a more ordered state. The coal-sawdust blends were found to be suitable for the production of bio-oil as the individual sawdust contained a higher number of volatiles, whereas the coal-hemp blends were better suited for the production of biochar since the individual hemp produced more residue after co-pyrolysis. Hemp biochar was further characterised by FTIR, TGA, GCV, and SEM-EDX analysis to investigate its potential in environmental and energy applications.

Sawdust-biomass based materials for sequestration of organic/inorganic pollutants and potential for engineering applications

Abstract: Sawdust materials are global wastes obtained from wood processing and exploitation activities. They are usually dumped/stored in uncontrolled conditions, thus becoming a major contributor to environmental pollution. Over the years, drastic efforts have been placed on converting these materials to a carbon source that can be applied for wastewater treatment. This places value on sawdust usage to ensure a green, clean, and sustainable environment thereby contributing to the global waste management system. The present review aims at presenting an empirical analysis and methodological approaches on sawdust-biomass-based material for the adsorptive removal of different pollutants from an aqueous solution. The first few parts revealed the hope and fate of sawdust-biomass-based materials in the environment, the health effects of sawdust on human and aquatic lives, and the environmental effects. This study further presents the source, types, composition, fabrication and configuration of sawdust adsorbents and characterization of the adsorbents derived from sawdust-biomass-based materials. The categories of pollutants considered in this study were grouped into endocrine-disrupting chemicals, dyes, pesticides, herbicides and agrochemicals, and heavy metals. A comprehensive review and the corresponding performance of sawdust-biomass-based adsorbents for each pollutant category was presented independently, and comparisons was made in each class. Adsorption capacity of different sawdust-based adsorbents ranged from 10 to 667.9 ​mg/g (for endocrine-disrupting chemicals and other emerging contaminants removal), 69.44–372 ​mg/g (for pesticides, herbicides, and agrochemicals removal), 3.42–526.3 ​mg/g (for dyes removal) and 2.87–325 ​mg/g (for heavy metal removal). This study further discussed the adsorption mechanisms of these materials, strategies for enhancing the efficiency of sawdust-biomass-based adsorbents and a potential methodological approach for engineering application, which is absent in the literature. Lastly, this study highlighted important observations and conclusions relating to the knowledge gaps to foster the way forward for the materials towards ensuring more industrial applications.