Biomass Conversion and Biorefinery最新文献

Recent developments in reinforced plastics for a range of engineering applications have utilized natural fiber mat as a reinforcing material. The goal of the current work is to create a biocomposite material by adding a natural fiber mat with polymer. Areca fiber mats were combined with epoxy to fabricate five areca fiber mat-based biocomposites via the hand lay-up technique. These areca fiber mats were reinforced with epoxy in the number of mat layers or weight of fiber mat varying (0, 1, 2, 3, and 4). Tensile, flexural, and impact strengths of the manufactured areca fiber mat composite were investigated. We used SEM to conduct a morphological examination on specimens that had undergone tensile and flexural fracture. The thermogravimetric analysis (TGA) method was used to study the thermal strength of the novel areca fiber mat composites. We also conducted experiments on water absorption and biodegradability. The results indicated that the morphologies of the composites enhanced the mechanical characteristics by increasing the bonding between the epoxy and areca fiber mat. The three-layer areca fiber mat composite has better mechanical strength (tensile 41.8 MPa, flexural 192 MPa, and impact 2.9 J) and thermal qualities (highest thermal stability 17.9 %) than the other four composites. SEM scans also support the areca fiber mat composite.

In order to improve the milling efficiency and wear resistance of hammer mills, diamond grains were brazed onto a T-shaped SUS 304 stainless steel hammer with an orderly patterned arrangement. The impact of grain arrangement patterns, size, and density on the milling efficiency and wear resistance of the hammer was investigated through the milling of maize kernels under an actual hammer milling condition. The milled maize powder and wear characteristics of the brazed diamond hammer were observed using a scanning electron microscope (SEM), and the particle size distribution of milled maize powder was analyzed using a laser particle size analyzer, and the wear of the hammers was measured by an electronic balance. The hammer with brazed diamond grains exhibited a significant increase in milling efficiency and wear resistance, surpassing that of the SUS 304 stainless steel hammer by more than 1.76 and 8 times, respectively. Optimal milling efficiency was attained through the use of brazed diamond grains incorporating an inclined arrangement pattern, small grain size, and low arrangement density. On the other hand, hammers with normal arrangement patterns, large grain size, and high arrangement density of diamond grains demonstrated superior wear resistance. The brazed diamond hammer takes into account both milling efficiency and wear resistance, because the orderly brazed diamond grains result in a substantial increase in the contact area with the material, thereby enhancing impact and friction. By appropriately selecting the arrangement patterns, density, and grain size of diamond grains, hammers with varying levels of milling efficiency and wear resistance can be obtained.

Polluted water sources are a growing concern in our world today, with more and more of our precious freshwater sources becoming contaminated. Pollution can come from a variety of sources, such as industrial discharge, agricultural runoff, and even urban runoff. Several treatment technologies have been investigated, mainly for dye pollution from textile and industrial wastes. In this study, the biosorption of methylene blue dye from the water environment was examined utilizing a low-cost and biodegradable biomaterial. Waste fish scales modified with NaOH were used as biomaterial. The biosorption effect of methylene blue concentration and pH variables was optimized. SEM for the surface morphology of the biomaterial and FT-IR analyses for the detection of functional groups were performed. The characterization of methylene blue biosorption was conducted to fully understand its nature, including its kinetics, equilibrium, and thermodynamic works. It has been determined that the biosorption process conforms most closely to the pseudo-second-order kinetic model for its kinetic results and to the Langmuir isotherm for its equilibrium results. Based on the Langmuir isotherm data, the maximum capacity for biosorption (q_max) was found to be 344.82 mg g⁻¹. The thermodynamic results showed that the process of biosorption of methylene blue on various surfaces is spontaneous and occurs via physisorption. Additionally, the experimental design method was utilized to determine the optimum conditions of the methylene blue biosorption process under various conditions. The maximum biosorption capacity was determined to be 102.367 mg g⁻¹ at the optimal conditions. The potential of biosorbent derived from the waste fish scales is promising as a novel biosorbent material due to its unique surface morphology and high biosorption capacity.

The composite industry is focusing on bio-waste as an alternative source of raw materials to address sustainability challenges in its procedures and goods. This study describes the characteristics of Licuala grandis tree peduncle fibers (LGPFs), a novel agro-waste that is segregated from the peduncle of the tree. Quantifiable information about LGPF, such as its tensile strength (232–273 MPa), Young’s modulus (2.2–4.9 GPa), better crystallinity index (51%), and cellulose proportion (58.31 weight percent), is obtained owing to the thorough examination. Thermogravimetric (TGA/DTG) and differential scanning calorimetry (DSC) inquiries provide insight into the LGPF’s thermal behavior and reveal that it will remain stable up to 236 °C. The analysis of Fourier transform infrared spectroscopy (FTIR) spectroscopy helps to validate the outcomes of chemical examination. Scanning electron microscope (SEM) analysis of the LGPF’s surface roughness supported the idea of using it as reinforcement material in composites with polymer as matrix. LGPF-reinforced polymer composites can be used in structural applications, according to the experimental findings.

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The newly isolated Coelastrella striolata var. multistriata strain 047 derived from humic acid rich peat soil was identified and cultivated in water-soluble humic acid (WSHA) to replace the commercial AF-6 as cultivation media. The results suggested that 75% WSHA ratio showed the highest specific growth rate at 0.46/day. Moreover, cultivation of strain 047 in 75% WSHA under high light intensity of 20,000–25,000 lx resulted in 26.67 mg/L·day biomass productivity which was 1.6 times higher than in AF-6 media. Lipid production was also elevated to 46.97 mg/L with significantly increased lipid productivity of 6.71 mg/L·day by utilizing WSHA media. Fatty acid profile was dominated with oleic acid (30.5%), followed by α-linolenic acid (27.1%) and palmitic acid (16.3%), demonstrating the feasible production of omega-3, omega-6, and omega-9 fatty acids. Substitution of AF-6 to WSHA may reduce the medium preparation cost up to 92%, which highlighted that WSHA media can be used for sustainable productions of biomass, lipids, and valuable fatty acids of Co. striolata var. multistriata strain 047, especially during cultivation in high light intensity.

This study investigated the valorization possibilities of indigenous marine biomass: blue-green microalgae, Chlorophyta (macroalgae), de-oiled Jatropha curcas, Moringa oleifera and Azadirachta indica (neem) seeds as bio-adsorbents. The de-oiled seed cake was obtained using n-hexane with a solid-to-solvent ratio of 1:6 for 1 h at 60 °C. These biomass feedstocks were chemically activated by 0.2 M phosphoric acid (H₃PO₄) at 120 ± 5 °C for 24 h, solar-dried and calcined at 650 °C for 2 h to prepare the desired carbon materials. Further, the set of bio-adsorbents has been comprehensively characterized to determine moisture content, ash content, bulk density, structural analysis, morphological analysis, particle size distribution and specific surface area. The characterization results were benchmarked with commercial activated carbon (AC), and the studied bio-adsorbents presented desired physicochemical characteristics for adsorption purposes. Therefore, the bio-adsorbents were applied against an inorganic dye, methylene blue (MB) dye from local textile process water in Pakistan. The adsorption capacity of blue-green microalgae, Chlorophyta macroalgae, J. curcas seed, M. oleifera seed and A. indica seed was obtained as 37.5 mg/g, 22.18 mg/g, 18.6 mg/g, 23.1 mg/g and 44.3 mg/g at the equilibrium point through batch adsorption, respectively. The adsorption data were fit to the linear, Freundlich and Langmuir isotherm models. Blue-green microalgae, Chlorophyta macroalgae, M. oleifera seed and J. curcas seed bio-adsorbents were the best fitted by the Freundlich model with R² = 0.9832, 0.9747, 0.9732 and 0.8786, respectively. A. indica seed bio-adsorbent was the best fitted by the linear isotherm model with R² = 0.9729. Besides, the bio-adsorbents set was as effective as commercial AC against organic pollutants such as chemical oxygen demand (COD), total nitrogen (TN) and total organic carbon (TOC) removal efficiency. The maximum COD, TN and TOC removal efficiency were obtained, by A. indica seed bio-adsorbent with 31.88%, 33.30% and 9.29%, respectively, while the COD, TN and TOC removal efficiency of commercial AC were 28.59%, 16.66% and 11.75%, respectively. Therefore, it can be concluded that the abundant marine biomass and de-oiled seed cake derived from A. indica seed as bio-adsorbents can be valorized to treat process water from local textile industries in Pakistan.

Phytoremediation is a cost-efficient process for removing contaminants from wastewater, soil, and sediments. This study used Lemna minor in a vertical subsurface flow system to treat wastewater at the Al-Muamirah facility in Babylon, Iraq, by evaluating the biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) from 31 October 2023 to 14 March 2024 using batch-mode wastewater input. The mean influent flow rate was 0.05278 m³/day ± 0.015 m³/day with a detention time for all parameters of 5 days, except for the nitrate parameter (TN and TP) examinations equal to 8 days. A VF basin was also used for comparison. Results showed that Lemna minor’s removal efficiencies for BOD, COD, TN, TP, and TSS were 93.26, 84.87, 70.58, 71, and 83.73%, respectively. The VF unit showed lower removal values but still performed effectively. These findings highlight the potential of Lemna minor for efficient and sustainable wastewater treatment, especially in areas with limited access to conventional wastewater treatment technologies.

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The present study focused on optimizing the biosorbent production through chemical modification of natural coconut fibers (NCFs) using a biorefinery process combined with nanoparticle impregnation and its adsorptive performance for removing Rhodamine B (Rh-B) and methylene blue. NCF was chemically modified via the formosolv process using formic acid (85% wt.) and 2% v/v HCl as catalyst at 100 °C for 1 h under atmospheric pressure, yielding formosolv coconut fiber (FCF). Nanomagnetic composites (NCF/Fe₃O₄ and FCF/Fe₃O₄) were produced through wet co-precipitation by mixing FeSO₄·7H₂O and FeCl₃·6H₂O salts (1:2 mol/mol) in an alkaline medium at different concentrations. This process generated four biosorbents, such as NCF, FCF, NCF/Fe₃O₄, and FCF/Fe₃O₄, which were characterized by chemical composition, XRD, FTIR, and magnetic properties. (1) The biorefinery process caused a chemical modification in the fibers, increasing the cellulose content and the crystallinity indexes. (2) The formosolv process enhanced the iron incorporation. (3) FCF exhibited the highest Rh-B removal efficiencies (REs), approximately 98% for FCF and 74% for FCF/Fe₃O₄. (4) For MB, RE values were 98% for FCF and 93% for FCF/Fe₃O₄. (5) These biosorbents were produced via a simple, fast, and cost-effective methodology and showed great potential for adsorption purposes. (6) Isotherms revealed distinct behaviors for the dyes, indicating different interactions with adsorbents. (7) Rh-B fitted better to the Freundlich model, suggesting a physisorption mechanism, while MB showed better fitting to the Langmuir model, suggesting the occurrence of chemisorption. (8) Thermodynamic parameters indicated that the adsorption of both dyes was endothermic and spontaneous for all biosorbents. (10) Biorefinery-processed fibers exhibited higher enthalpy values, indicating stronger interaction with MB and Rh-B. (11) Regeneration studies suggested that a higher NaOH concentration enhanced the desorption efficiency. Overall, the proposed modification routes have demonstrated the capability to produce eco-friendly magnetic biosorbents with high adsorption potential through a simple, fast, and low-cost approach.

In this study, Chlorella vulgaris and aerobic bacteria were co-cultured for the treatment of mixed wastewater with different C:N ratios (5:1, 10:1, 15:1, 20:1, and 25:1). The results showed that the C:N ratio had a significant effect on the growth and treatment efficiency of microorganisms. The low C:N ratio system facilitated the growth of Chlorella, whereas the high C:N ratio system was more beneficial to the growth of aerobic bacteria. As the C:N ratio increased, the chlorophyll content increased and then decreased, and yet the carotenoid content changed in the opposite direction. In all systems, pH gradually increased with incubation time, while dissolved oxygen content first decreased and then increased. The maximum total biomass was obtained from the 15:1 ratio with a value of 0.63 ± 0.02 g/L, where Chlorella and bacteria accounted for 30.68% and 69.32%, respectively. Meanwhile, when treating wastewater with a C:N ratio of 15:1, the microalgal-bacterial consortia system presented the highest removals of COD, NH₃-N, and TP, accounting for 60.89 ± 1.80%, 43.38 ± 1.00%, and 68.55 ± 0.59%, respectively.

The primary objective of this work was to investigate the synthesis and the bioactivity of SeNPs encapsulated with exopolysaccharide (EPS). The EPS was mainly composed of 395 ± 13.20 mg/g carbohydrate and 121 ± 3.21 mg/g protein; the following moiety was used for surface stabilization of selenium nanoparticles (SeNPs). Bioactive SeNPs, i.e., EPS-SeNPs, with an average size of 43.7 ± 13.7 nm, were successfully synthesized. The antibacterial bioactivity of EPS-SeNPs was seen to be enhanced against Gram-positive bacteria, viz., Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis, as well as Gram-negative bacteria, such as Escherichia coli and Salmonella enterica. In addition, the study also demonstrated antifungal activity against Alternaria alternata, Fusarium laterium, and Aspergillus niger. The cytotoxic activity of synthesized EPS-SeNPs exhibited a dose-dependent response against liver carcinoma cell lines, i.e., the HepG2. These findings support the hypothesis that these nanoparticles hold potential as an emerging material in the field of therapeutics.