Integrated enzymatic processes for next-generation biodiesel production

High-defect sulfonated carbon derived from beet molasses for effectively biodiesel production by esterification of methanol and oleic acid

Synthesis of silica/soda lime composite catalyst from rice husk ash for efficient biodiesel production

Sustainable biodiesel production from wild seed oil crop Malcolmia africana using green tea waste-derived copper nano catalyst

Integration of agro wastes as an alternative substrate for microalgae cultivation: A review

Three-Dimensionally ordered macro-mesoporous ZrTiO4 supported polyoxometalate-ionic liquid hybrid for efficient biodiesel production from low-quality oils

Retraction notice to "Catalytic biodiesel production from Jatropha curcas oil: A comparative analysis of microchannel, fixed bed, and microwave reactor systems with recycled ZSM-5 catalyst" [Environ. Res. 258 (2024) 119474

Optimized lithium-impregnated silica catalyst from corn cob waste for enhanced biodiesel production: Structural tuning and circular economy application

Comparative analysis of biodiesel production from Alphonso and Bangalora seeds: Quantitative and qualitative characterization and their application

A novel peanut shell-derived biochar/KOH heterogeneous catalyst for biodiesel production from waste cooking oil: RSM optimization and diesel engine performance assessment

Separation and characterisation of crude hydrogenase from Cupriavidus necator H16 grown on waste glycerol

Defect engineering provides new opportunities to overcome the intrinsic limitations of metal-organic frameworks (MOFs) in photocatalysis. Herein, a cluster-defect engineering (CDE) strategy is employed to modify the pristine UiO-66 framework, wherein Zn incorporation followed by selective acid etching yields defect-rich A/(Zn,Zr)UiO-66 catalysts featuring hierarchical porous architectures and abundant Lewis (L) acid sites. Optical and photoelectrochemical analyses confirm that CDE broadens visible-light harvesting, narrows the bandgap, and prolongs carrier lifetimes. The synergistic interplay between L acid sites and photocatalysis over A/(Zn,Zr)UiO-66 results in an excellent photocatalytic performance in biodiesel production via oleic acid (OA) esterification with methanol (CH3OH) under mild reaction conditions, outperforming pristine UiO-66. Notably, the optimized A/(Zn,Zr)UiO-66-0.2 achieves a remarkable 99.3% biodiesel yield under mild conditions, alongside superior stability and reusability. Further, in situ spectroscopic investigations and density functional theory (DFT) calculations disclose that CDE lowers the coupling barrier of OA and CH3O• radicals by strengthening OA adsorption and activation as well as facilitating charge stabilization at unsaturated Zr sites. This work highlights CDE as an ingenious strategy for tailoring the electronic configuration and interfacial chemistry of MOFs, offering a versatile platform for visible-light-driven biomass upgrading and sustainable fuel production.

Plant oils are typically converted into fatty acid methyl esters in biodiesel production using alcohol and chemical catalysts (KOH or NaOH). These catalysts harm the environment and are inefficient with oils high in free fatty acids. Thus, lipase enzymes have been developed as catalysts for transesterification, including esterification, transesterification, aminolysis, and lactonization. This study aims to obtain lipase enzymes for converting plant oils into biodiesel. Microorganisms were isolated, screened, and identified from palm oil mill effluent. The selected isolates were optimised for growth in Luria Bertani medium using the one-factor at a time method. The crude lipase enzyme was characterised for optimal temperature, pH, stability, and activator and inhibitor effects. The molecular weight was determined using SDS-PAGE and zymography. The lipase was then applied to enzymatic biodiesel production, with descriptive and qualitative data analysis. In this study, 65 strains were isolated from POME samples, identifying 5 with the highest lipase activity as Enterobacter cloacae. The lipase from E. cloacae showed optimal activity at pH 7 and 30 °C, with an active molecular weight of 21.38 kDa. Fe3+, Mn2+, Zn2+ ions, b-mercaptoethanol, acetone, and SDS enhanced enzyme activity, while Mg2+ ions, Tween 80, and Triton X-100. E. cloacae lipase converted plant oil to biodiesel with a yield of 96.91%.

Defatted microalgal biomass represents a potentially sustainable resource for biostimulant production, reducing waste from biodiesel processing while enhancing crop resilience to abiotic stress. This study evaluated the potential of defatted Chlorella sp. extract as a biostimulant to alleviate salinity-induced stress in barley (Hordeum vulgare) grown hydroponically under electrical conductivity levels of 2, 8, and 12 mS cm⁻¹. Gas chromatography-mass spectrometry (GC-MS) analysis of the ethanol extract revealed 28 bioactive compounds, mainly fatty acids and esters associated with plant growth promotion and stress tolerance. Among the three barley genotypes tested (Giza 123, Giza 132, and Giza 134), Giza 123 exhibited the greatest resilience to salinity, showing the highest grain yield and photosynthetic activity. Application of algal extract, particularly through the combined seed-soaking and foliar spray treatment, led to marked improvements, increasing grain dry weight by 37%, electron transport rate (ETR) by 22%, and P, K, and N grain contents by 9-14% compared to the control. These enhancements were accompanied by higher protein content (9.6%) and chlorophyll a concentration (0.41mg g⁻¹ FW). Significant genotype × treatment interactions indicated variable responses among cultivars. Overall, the results demonstrate that defatted Chlorella biomass extract serves as an effective and eco-friendly biostimulant, improving barley growth, nutrient uptake, and salinity tolerance while contributing to the circular valorization of algal residues.

This study explored a silica catalyst impregnated with APTES [(3-aminopropyl) triethoxy silane] for the transesterification of vegetable oil to biodiesel. Its aim was to enhance the activity of silica by adding various concentrations of APTES as a modifier, which would impart basic amine functional groups to the silica surface. Synthesis and functionalization of the silica were confirmed through the use of various characterization methods such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Spectroscopy), XRD (X-ray Diffraction), and BET (Brunauer-Emmett-Teller) surface area analysis. Of the four synthesized catalysts, the highest yield of biodiesel (62.2%) was obtained using the catalyst containing 0.75g of APTES, used at 65°C for 5h with 0.3g of catalyst. GC (Gas chromatography) showed a promising FAME (fatty acid methyl esters) profile, which suggests the FAME would have good properties essential to low temperatures, as well as aiding in the biodiesel cold flow properties. The catalyst retained over 90% of its catalytic activity after three cycles, demonstrating excellent reusability. Although the maximum biodiesel yield achieved was 62.2%, the consistent activity over multiple runs confirms the material's stability and operational potential.

Efficient lipid production from macrofilamentous alga Vaucheria hamata FACHB-3853.

Sustainable biodiesel production via thermally induced transesterification using Meso-Macroporous silica derived from marine diatom following fucoxanthin extraction.

Advancements in production techniques have markedly enhanced potential glycerol applications across various sectors. The present study describes the purification of two different samples of crude glycerol obtained from industrial processes. First, the purification of crude glycerol (pH = 5) was achieved by treatment with KOH and subsequent adsorption on commercial activated charcoal. K2SO4 was also obtained as a byproduct of the process. The purification of crude glycerol (pH = 12) was also achieved by treatment with H3PO4 and subsequent adsorption on commercial activated charcoal. KH2PO4 was also obtained as a byproduct of the process. The purified glycerol was analyzed by IR, 1H and 13C NMR, and the ASTM D4176-22 method (standard test method for free water and particulate contamination). ASTM D874 is the standard test method for determining the sulfated ash content. The test is used to measure the amount of inorganic contaminants (ash-forming materials) such as abrasive solids and catalyst residues that might remain in glycerol after the purification process. These materials often contain metals such as calcium, potassium, and sodium, and ASTM D664 is a standard potentiometric titration method to determine the total acid number in fatty acid methyl esters (biodiesel or biofuel) by measuring free fatty acids and mineral acids, expressed as mg KOH/g; while not directly used for glycerol, it is crucial for determining glycerol quality because crude glycerol from biodiesel production contains impurities such as free fatty acids that ASTM D664 quantifies, helping to determine if glycerol is suitable for further processing. Subsequently, glycerol was applied directly in the formulation of a hand sanitizer. The hand sanitizer was prepared by mixing water, glycerol, hydroxyethylcellulose, and a solution of methylparaben-ethanol. Methyl salicylate was added to the formulation after the homogenization process, and a hand sanitizer without methyl salicylate was prepared for comparison. In the context of ecosustainable formulation design, this study addresses the self-aggregation of glycerol and methyl salicylate with a wide range of physicochemical and biological activities in hand sanitizer. The physicochemical properties of the formulation were determined in a preliminary analysis of the properties of the hand sanitizer. The pH of the hand sanitizers was slightly acidic (5.7), and despite their high viscosities, the formulations had a high degree of spreadability. The aggregation of methyl salicylate was determined at concentrations up to 40-50 wt %. These results provide basic knowledge to promote the exploration of glycerol and methyl salicylate as valuable ingredients in formulations for various applications.

Deep learning based optimization of biodiesel production from high free fatty acid milk scum oil using synthetic process data and ablation analysis

One of the competitive crops grown in Ukraine is camellia (Camelina sativa). In recent years, camellia has become widely used as a crop in the USA and EU countries, as it is an energy crop and is considered a potential renewable source for biodiesel production. The content of omega-acids in the oil can reach 53—55 % in the oil, which increases the nutritional and biological value of this product. The effectiveness of growing red clover using digestate obtained during fermentation of crushed vegetable waste as an organic fertilizer has been proven. It has been determined that the liquid fraction of the digestate contains about 1000 mg/l of nitrogen-containing components and 480 mg/l, therefore its preliminary dilution with water is required before further use as a fertilizer. The optimal dilution is 1:15 and 1:22, respectively, for the first and second phases of red clover growth. Morphological indicators and the estimated yield value of red clover when grown on digestate are higher than when using nitrofoska. It was found that when pre-sowing treatment of red clover seeds with digestate, the plant height was 75 cm, the number of branches was 10, the number of seeds per plant was 995 pcs., while the mass of seeds from one plant was 1.054 g. Considering that the calculated plant density was 247/m2, and the mass of seeds from 1 m2 is 260.3 g, it can be calculated that the crop yield is approximately 2.6 t/ha. The yield of red clover calculated in a similar way when using nitrofoska was 1.672 t/ha, in the control — 0.690 t/ha. This research was conducted within the framework of an ongoing Jean Monnet grant: Waste Management in the Context of Transition to a Circular Economy: the EU Experience (101172378 — CIRCLEMAN — ERASMUS-JMO-2024-HEI-TCH-RSCH)).