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The shocking ecological variations and dangers of phasing out fossil fuels are concerning for human progress. It has raised the apprehension of workers about shifting from old energy capitals to ecologically sustainable biofuels. The current work involves the preparation of biodiesel (BD) using non-edible neem oil via transesterification reaction (TR). The transesterification process was carried out using nickel-doped zinc oxide (Ni–ZnO) nanocatalysts produced using the sonochemical technique. XRD, EDX, and SEM were employed for characterizing synthesized nanoparticles. TR was performed for the evaluation of the catalytic performance of Ni–ZnO. Various parameters affecting reaction rates, such as catalyst amount, temperature, and the methyl alcohol to neem oil ratio, were tested to determine where the maximum BD production could be achieved. It was found that the best BD (90.1%) was produced at 60 °C with a 1:10 oil-to-methyl alcohol ratio using 0.9 g of the catalytic system. First-order kinetic modeling is best suited for TR. Vital thermodynamic factors such as energy of activation (E*), enthalpy (H*), and entropy (S*) were also found. TR was endothermic and entropy-driven. A Ni–ZnO nanocatalyst could be an appropriate catalytic system for the heterogeneous catalysis of transesterification, a key reaction for BD making. [ABSTRACT FROM AUTHOR]

Vitrimer materials have attained great interest owing to their sustainable functions and distinctive physical properties. Compared with conventional cross‐linked materials, the thermoplastic‐like nature, such as the stress relaxation and creep at high temperatures, is outstanding, which is owing to the activation of the bond exchange in the cross‐linked network. The activation temperature of the bond exchange, so‐called topology freezing temperature (Tv), are treated as the important material parameters, and non‐isothermal (i.e., temperature‐ramp) creep test is one of the method to determine the Tv. This study investigates effects of network defects, that is, the breaking point of network connectivity, on the creep and Tv. The transesterification vitrimer samples with varying fraction of the network defects are designed using thiol‐epoxy click reaction, where the overall fraction of the bond exchange units, that is, the ester bond and hydroxyl group, is kept constant. Non‐isothermal creep tests are conducted with varying temperature‐ramp rate and applied stress levels, and the difference of Tv and creep behaviors at T > Tv are discussed in terms of network strand diffusion during bond exchange and chain elongation under stress. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The quest for eco-friendly alternatives to conventional fossil fuels intensifies amid the global transition to sustainable energy sources. With petroleum-based products dominating over 95.00% of the fuel market, concerns about their limited biodegradability and high eco-toxicity escalate. Addressing this, there's a rising demand for biobased solutions to mitigate pollution and cut greenhouse gas emissions. This study focuses on synthesizing biodiesel from waste almond seed oil (WCO) using an innovative bifunctional catalyst derived from waste animal bones and almond shells. Characterization via scanning electron microscopy, X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, and Brunauer, Emmett, and Teller analysis confirms the efficacy of the catalyst. Physicochemical properties of WCO and the resulting biodiesel align with ASTM D6751 and EN 14214 standards. Employing Box-Behnken design, we optimized the catalytic process by exploring key parameters, resulting in an impressive biodiesel yield of 86.20%. The optimal parameters were a methanol:oil ratio of 6.026, catalyst loading of 1.49917 wt%, reaction time of 66.8179 minutes, and temperature of 59.9806℃. Our findings underscore the potential of utilizing waste materials for sustainable biodiesel production, with the developed bifunctional catalyst offering a cost-effective and environmentally friendly alternative, contributing to cleaner fuel production methods. [ABSTRACT FROM AUTHOR]

In this investigation, a strongly acidic exchange resin was used for the transesterification of methyl acetate with n‐propanol, n‐butanol, and iso‐butanol. Kinetic and equilibrium experiments for the three systems were conducted using a temperature‐controlled batch reactor setup. The effects of the following operating parameters on the transesterification were explored: reaction temperature, catalyst loading, and methyl acetate‐to‐alcohol molar ratio. The conversion of the limiting reactant in the reaction mixture increased with increasing reaction temperature, catalyst loading, and varying reactant proportions from 1:1 to other ratios. It was found that excess methyl acetate would result in higher limiting reactant conversion than using excess alcohol with the same initial molar proportionality between the excess and the limiting reactants. It was found that an increase in the chain length of the alcohol and/or branching suppressed the conversion of the reactants owing to steric hindrance. To mathematically correlate the data, several kinetic models were tested, and the Eley–Rideal model was selected. Accordingly, a reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Spinel nanomaterial of ZnFe2O4 has been successfully synthesised and its high crystallinity is confirmed by x-ray diffraction analysis in the Fd3m space group with crystallite size of around 37.96 nm. The agglomerated nature of the sample is confirmed through SEM analysis and compositional analysis using EDS. The maximum yield of 94.66% biodiesel is obtained at 15 min, 50°C temperature, 6 weight % catalyst, and 6:1 ethanol: oil conditions. The FTIR analysis and ¹H-NMR analysis of waste cooking oil and biodiesel of different yields confirm the different functional groups exist in the sample and the biodiesel. The physio-chemical properties of the biodiesel match well with the literature values. The reusability of the ZnFe2O4 confirms the yield of 80.9% after 3 cycles under the same reaction conditions. [ABSTRACT FROM AUTHOR]

Ring‐opening polymerizations (ROPs) of l‐lactide (LA) were performed with ethyl l‐lactate or 11‐bromoundecanol as initiators (In) and tin(II) ethyl hexanoate (SnOct2) as catalyst (Cat) using four different LA/In ratios (20/1, 40/1, 60/1, and 100/1). One series of ROPs was conducted in bulk at 120 °C, yielding PLAs with low dispersities (Ð ~ 1.2–1.4), and a second series was conducted in bulk at 160 °C, yielding higher dispersities (Ð ~ 1.3–1.9). Samples from both series were annealed for 1 or 14 days at 140 °C in the presence of SnOct2. Both polycondensation and disproportionation reactions occurred, so that all four samples tended to form the same type of molar mass distribution below 10,000 Da, regardless of their initially different number average molar masses (Mn). Both initiators gave nearly identical results. The thermodynamic control of all reversible transesterification processes favored the formation of crystallites composed of chains with a Mn around 3500–3700, corresponding to a crystal thickness of 10–13 nm. [ABSTRACT FROM AUTHOR]

In-situ stirring batch reactor transesterification is a widely used method for the conversion of various biomass into biodiesel, particularly Nannochloropsis sp microalgae. Therefore, this study aims to investigate the effect of CaO/Hydrotalcite catalyst loading ratio and stirring rate on in situ stirring batch reactor transesterification of Nannochloropsis sp microalgae to produce biodiesel. In-situ transesterification was carried out using stirring with a four-blade paddle (50 w), while CaO/Hydrotalcite catalyst preparation was performed using incipient wetness impregnation. Nannochloropsis sp microalgae were then converted into biodiesel with varying loading ratio of catalyst (1:1, 3:1, and 5:1 %wt/wt) and stirring speed of agitation (50, 100,150, 200, and 250 rpm) for 4 hours (60oC). Subsequently, biodiesel obtained from the process was analyzed using gas chromatography (GC). The results showed that the surface area of CaO/Hydrotalcite was 45.756 m2/g. The conversion yields of Nannochloropsis sp microalgae to biodiesel with CaO/Hydrotalcite reached 38.36% with an agitation rate of 250 rpm. Based on the fatty acids analyzed using GC methods, the products predominantly contained olefine (61.49%) and gasoline (38.51%). [ABSTRACT FROM AUTHOR]

Background: Sophorolipids (SLs) are a class of natural, biodegradable surfactants that found their way as ingredients for environment friendly cleaning products, cosmetics and nanotechnological applications. Large-scale production relies on fermentations using the yeast Starmerella bombicola that naturally produces high titers of SLs from renewable resources. The resulting product is typically an extracellular mixture of acidic and lactonic congeners. Previously, we identified an esterase, termed Starmerella bombicola lactone esterase (SBLE), believed to act as an extracellular reverse lactonase to directly use acidic SLs as substrate. Results: We here show based on newly available pure substrates, HPLC and mass spectrometric analysis, that the actual substrates of SBLE are in fact bola SLs, revealing that SBLE actually catalyzes an intramolecular transesterification reaction. Bola SLs contain a second sophorose attached to the fatty acyl group that acts as a leaving group during lactonization. Conclusions: The biosynthetic function by which the Starmerella bombicola 'lactone esterase' converts acidic SLs into lactonic SLs should be revised to a 'transesterase' where bola SL are the true intermediate. This insights paves the way for alternative engineering strategies to develop designer surfactants. [ABSTRACT FROM AUTHOR]

In this study, hybrid skeleton material ZIF-8@ZIF-67 was synthesized by the epitaxial growth method and then was utilized as a carrier for encapsulating Pseudomonas fluorescens lipase (PFL) through the co-precipitation method, resulting in the preparation of immobilized lipase (PFL@ZIF-8@ZIF-67). Subsequently, it was further treated with glutaraldehyde to improve protein immobilization yield. Under optimal immobilization conditions, the specific hydrolytic activity of PFL@ZIF-8@ZIF-67 was 20.4 times higher than that of the free PFL. The prepared biocatalyst was characterized and analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR). Additionally, the thermal stability of PFL@ZIF-8@ZIF-67 at 50 °C was significantly improved compared to the free PFL. After 7 weeks at room temperature, PFL@ZIF-8@ZIF-67 retained 78% of the transesterification activity, while the free enzyme was only 29%. Finally, PFL@ZIF-8@ZIF-67 was applied to the neryl acetate preparation in a solvent-free system, and the yield of neryl acetate reached 99% after 3 h of reaction. After 10 repetitions, the yields of neryl acetate catalyzed by PFL@ZIF-8@ZIF-67 and the free PFL were 80% and 43%, respectively. [ABSTRACT FROM AUTHOR]

The impact of heterogeneous catalytic systems, which are based on rare earth metals, on the properties of biodiesel produced via the transesterification process in a stationary reactor (autoclave) was thoroughly investigated. The physicochemical attributes, including the specific surface area, were analyzed employing the Brunauer–Emmett–Teller (BET) method. The basicity and acidity levels of the catalytic systems were evaluated through temperature-programmed desorption of ammonia and carbon dioxide (TPD-NH3, TPD-CO2), respectively. Furthermore, High-Performance Liquid Chromatography (HPLC) analysis facilitated the assessment of triglyceride conversion and the determination of methyl ester (FAME) selectivity within these processes. Our findings indicate that catalytic systems augmented with lanthanum showcased superior performance. A significant correlation was discerned between the conversion and selectivity to methyl esters and both the specific surface area and the acidity and basicity properties of the catalytic systems under study. These results underscore the crucial role that the physicochemical characteristics of catalytic systems play in optimizing the transesterification process, thereby enhancing the quality of the produced biodiesel. This study contributes valuable insights into the development of more efficient and effective biodiesel production methodologies, highlighting the potential of rare earth metal-based catalysts in renewable energy technologies. [ABSTRACT FROM AUTHOR]

3D printing is a low cost, customizable, and fast‐growing technology with the potential to revolutionize plastic manufacturing. Vat photopolymerization 3D printing technologies stand out for their high resolution, however, the resulting printed materials are made from petroleum feedstocks and are covalently crosslinked which renders them unrecyclable. Here, resin formulations with 70 wt% bio‐based content and dynamic functionality are synthesized and printed using lignin, vanillin, and soybean oil components. These printed polymers can undergo dynamic transesterification due to the methacrylated lignin (LMA) to allow for self‐healing capabilities; therefore, potentially increasing the materials lifetimes compared to traditional thermoset materials, offsetting the use of traditional petroleum‐based resins, and lowering their environmental impact. The LMA also provides the thermosets with better mechanical performance and thermal stability in comparison to the controls. Additionally, compatibility with 3D printing technologies improves the competitiveness of biobased plastics with conventional materials. [ABSTRACT FROM AUTHOR]

This study explores the innovative application of iron filings solid waste, a byproduct from mechanical workshops, as a heterogeneous catalyst in the production of biodiesel from waste cooking oil. Focusing on sustainability and waste valorization, the research presents a dual-benefit approach: addressing the environmental issue of solid waste disposal while contributing to the renewable energy sector. Particle size distribution analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), Thermal analysis (TG-DTA), and FTIR analysis were used to characterize the iron filings. The response surface methodology (RSM) was used to guide a series of experiments that were conducted to identify the optimum transesterification settings. Important factors that greatly affect the production of biodiesel are identified by the study, including catalyst loading, reaction time, methanol-to-oil ratio, reaction temperature, and stirring rate. The catalyst proved to be successful as evidenced by the 96.4% biodiesel conversion efficiency attained under ideal conditions. The iron filings catalyst's reusability was evaluated, demonstrating its potential for numerous applications without noticeably decreasing activity. This work offers a road towards more environmentally friendly and sustainable chemical processes in energy production by making a strong argument for using industrial solid waste as a catalyst in the biodiesel manufacturing process. [ABSTRACT FROM AUTHOR]

Recent years have seen an increase in research on biodiesel, an environmentally benign and renewable fuel alternative for traditional fossil fuels. Biodiesel might become more cost-effective and competitive with diesel if a solid heterogeneous catalyst is used in its production. One way to make biodiesel more affordable and competitive with diesel is to employ a solid heterogeneous catalyst in its manufacturing. Based on X-ray diffraction (XRD) and Fourier Transform infrared spectroscopy (FTIR), the researchers in this study proved their hypothesis that iron oxide core–shell nanoparticles were generated during the green synthesis of iron-based nanoparticles (FeNPs) from Camellia Sinensis leaves. The fabrication of spherical iron nanoparticles was successfully confirmed using scanning electron microscopy (SEM). As a heterogeneous catalyst, the synthesised catalyst has shown potential in facilitating the conversion of algae oil into biodiesel. With the optimal parameters (0.5 weight percent catalytic load, 1:6 oil—methanol ratio, 60 °C reaction temperature, and 1 h and 30 min reaction duration), a 93.33% yield was attained. This may be due to its acid–base property, chemical stability, stronger metal support interaction. Furthermore, the catalyst was employed for transesterification reactions five times after regeneration with n-hexane washing followed by calcination at 650 °C for 3 h. [ABSTRACT FROM AUTHOR]

This document provides technical information about the synthesis and characterization of alkyl ether phospholipids, specifically 1-alkyl-2-acyl-sn-glycero-3-phosphoethanolamines (1-alkyl-2-acyl-GPEs). The authors have developed a novel phosphorylating agent that allows for the synthesis of these compounds, overcoming limitations of traditional methods. The document includes detailed synthesis routes, purification methods, and analytical test results for different derivatives of the compound. The compounds are referred to as 1-alkyl-2-acyl-GPE 12a, 12b, and 12c, and the document also includes an acknowledgment and dedication to Professor Koichi Narasaka. [Extracted from the article]

A microwave-assisted synthesis of dialkyl and cyclic H-phosphonates via bis(2,2,2 trifluoroethyl) phosphonate (BTFEP) is described. This method enables the synthesis of various cyclic H-phosphonates and hetero-substituted dialkyl H-phosphonates by simple alcoholysis under non-inert and additive-free conditions. Short reaction times and the requirement for only stoichiometric amounts of alcohol render this method attractive for synthetic applications. [ABSTRACT FROM AUTHOR]

This investigation aimed to enhance the functionality and minimize the harmful emissions of a diesel engine operating under various fuel blends, engine loads, and speeds using both standard techniques and an experimentally designed table (L16 orthogonal array) made with Taguchi's strategy of experimental design. The investigation's design had three governing parameters: fuel type, engine load, and engine speed. Each of these had four levels. The L16 orthogonal array (OA) was used to measure the operational characteristics, such as brake thermal efficiency (BTE) and brake-specific energy consumption (BSEC), as well as the pollution attributes such as brake-specific hydrocarbon (BSHC), brake-specific carbon monoxide (BSCO), and brake-specific nitrogen oxide (BSNO). Signal-to-noise (S/N) ratio and grey analysis were used to find the engine's best operating state so that it could get the most out of its performance while putting out the least amount of pollution. The study showed that engine load was the most influencing parameter for both BTE and BSEC, with contribution ratios of 84.02% and 86.79%, respectively. At 25% engine load, 1000 rpm, and using 20% orange peel biodiesel blended 100 ppm CNT impregnated diesel (OPB20CNT100) fuel (A1–B1–C4), the emissions of BSCO, BSNO, and BSHC were at their lowest levels. Engine load has the most significant impact on emissions. The engine's BSEC reduces by 4.35%, and BSNO emissions increased by 1.24%. BTE, BSCO, and BSHC emissions dropped by 3.1%, 16.96%, and 40.06%, respectively, under the best operating conditions compared to diesel fuel. The investigation demonstrates that the application of Taguchi–Grey optimization technique improves both the operational performance and pollution characteristics of diesel engines. The results showed that biodiesel made from orange peel and impregnated with CNT may be utilized as a sustainable alternative to diesel fuel. [ABSTRACT FROM AUTHOR]

In this study, a biphasic system combining oil and ionic liquid was utilized for lipase-catalyzed transesterification of salmon oil and alcohol to concentrate n-3 PUFAs, notably EPA and DHA. Various process variables, such as enzyme type, quantity, alcohol chain length, temperature, reactant proportions, and ionic liquid selection, were systematically assessed to optimize the process and enhance the yield of these valuable fatty acids. It was found that the Novozym 435 and Lipolase 100L Type EX emerged as the most effective enzymes. The impact of varying alcohol chain lengths (C1–C8) was examined, revealing that the Novozym 435 enzyme displayed its peak synthetic activity with 2-propanol. The results revealed a substantial increase in the overall activity during the transesterification reaction when employing ILs featuring hydrophobic cations and anions with low nucleophilicity. Specifically, the [omim+][NTf2−] ionic liquid exhibited the highest level of activity. This research holds promise for more efficiently and sustainably obtaining concentrated n-3 PUFAs from fish oil while reducing environmental impact relative to other existing concentration processes. [ABSTRACT FROM AUTHOR]

This study specifically examines the process of producing and analyzing biodiesel made from castor oil using base-catalyzed transesterification. The catalyst used in this process is potassium hydroxide (KOH), and the methanol (CH3OH) used has a purity of 99.9%. The biodiesel obtained was analyzed extensively to assess its quality. The characterization techniques employed were Gas Chromatography (GC) for compositional analysis, Flash Point measurement for safety assessment, Kinematic Viscosity evaluation for flow properties, and Density determination for mass-volume relationships. To perform a statistical analysis, the Response Surface Method (RSM) was employed to determine the optimal conditions that would yield the highest rate of biodiesel production among the potential solutions. This study focused on three key variables affecting the transesterification process: ultrasonic duty cycle (using a 24 kHz ultrasonic method varying the duty cycle from 20% to 100%), ultrasonic amplitude (varying from 20% to 100%), and reaction time (spanning from 10 to 15 minutes). This investigation achieved a biodiesel yield of 88.38% using a 60% ultrasonic amplitude, a single ultrasonic cycle, and a 15-minute reaction time. The regression model developed can be used to predict biodiesel's percentage conversion. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation, neglectable corrosion, and environmental friendliness. Although great progress has been made in the preparation of solid strong base catalysts, it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction system. Here, we report a tandem redox strategy to prepare Na single atoms on graphene, producing a new kind of solid strong base catalyst (Na1/G). The base precursor NaNO3 was first reduced to Na2O by graphene (400 °C) and successively to single atoms Na anchored on the graphene vacancies (800 °C). Owing to the atomically dispersed of basicity, the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate (turnover frequency (TOF) value: 125.7 h−1), which is much better than the conventional counterpart Na2O/G and various reported solid strong bases (TOF: 1.0–90.1 h−1). Furthermore, thanks to the basicity anchored on graphene, the Na1/G catalyst shows excellent durability during cycling. This work may provide a new direction for the development of solid strong base catalysts. [ABSTRACT FROM AUTHOR]

Biodiesel made from renewable energy sources is gaining popularity due to its environmental and economic benefits. In this work, the effect of the most important reaction variables was investigated during the acid‐catalyzed of Spirulina sp. microalgae oil to biodiesel. Results showed that the biodiesel was obtained at 60°C for 8 h using 30 g of dry Spirulina sp. powder in 300 mL of n‐hexane. Physical characteristics of the biodiesel produced from Spirulina sp. were confirmed using, evaporation temperature, flash point, freeze point, and fire point. The presence of bonds of CH3, ROH, RC≡C‐H, ‐CH = CH‐CH2)n, R‐CH2‐X, and ArOH in the biodiesel 1H NMR spectrum. Further, the biodiesel produced from the Spirulina sp. subjected to FT‐IR and GC MS which revealed the aliphatic hydrocarbons and the list of compounds such as Oleic acid, 9‐octadecenal etc. [ABSTRACT FROM AUTHOR]

Calotropis gigantea, commonly known as Indian milkweed, is a prevalent plant in Asia. It typically thrives in open and unused areas, often considered a weed. This plant produces flowers and fruits consistently throughout the year, exhibiting a continuous flowering and fruiting cycle. This research investigated the viability of Calotropis gigantea seed oil as a potential source intended for biodiesel manufacturing. The oil was obtained from Calotropis gigantea seeds using hexane extraction in the Soxhlet apparatus. The seeds were determined to contain 33.3 wt% of oil content. The process of biodiesel production involved conducting a transesterification reaction. Further, the produced biodiesel was blended with pure diesel and three different nanoparticles, Titanium dioxide (TiO2), Chromium oxide (Cr2O3), and Silicon dioxide (SiO2), to evaluate combustion performance, and emission characteristics of a single-cylinder diesel engine under various load conditions. Incorporating Cr2O3 nanoparticles into the CGSB20 biodiesel blend yielded significant improvements in BTE, coupled with BSFC reduction. Specifically, in the CGSB20 + Cr2O3 fuel mixture, BTE increased notably by 31.2 %, reaching a value of 0.33 g/kWh for BSFC. Similarly, for the CGSB20 + SiO2 and CGSB20 + TiO2 blends, BTE experienced enhancements of 29.2 % and 28.1 %, respectively, while BSFC values were lowered to 0.37 and 0.4 g/kWh. Furthermore, the unchanging dispersal of nanoparticles within the CGSB20 blend exhibited extraordinary cylinder pressure and HRR values, reaching 77 bar and 34.2 J/CA, respectively. The CGSB20+ Cr2O3 blend yielded favorable emissions outcomes. Specifically, CO, NOx, UHC, and smoke emissions were approximately 4.5 g/kWh, 725 ppm, 0.11 g/kWh, and 23.6 %, respectively.

ABSTRACT Pittosporum resiniferum oil was extracted from the seed and the oil together with methanol was use for the production of biodiesel through transesterification process using novel solid base catalyst (K2CO3 supported on MgO). 0.6:5 (K2CO3 loaded on MgO), a 5 h calcination time, 600°C calcination temperatures were the optimum conditions under which the catalyst was prepared. FTIR, SEM, CO2‐TPD, XRD, N2 adsorption‐desorption, Hammett indicators and other techniques were used to characterize the catalyst. The molar ratio of methanol‐to‐oil, the catalyst amount, time of the reaction as well as the temperature of the reaction were examined. The study found that 16:1 methanol‐to‐oil molar ratio, 5% catalyst loading amount, a reaction time of 2.0 h, and a reaction temperature of 60°C were sufficient for a maximum yield of 97.4%. With relative high activity, the catalyst can perhaps be used again possibly for five times. The characteristics of the biodiesel produced were consistent with international standards.

The current study deals with the evaluation of vibrations and noise generated by a diesel engine powered by Calophyllum inophyllum biodiesel blend (B20) and molybdenum trioxide (MoO3) nanoparticles, predicted using machine learning algorithms. The nanoparticles were spread out in B20 at a level of 75 ppm, along with a surfactant and a dispersant to make sure they mixed evenly with the fuel samples. The stability of the nanoparticles was then tested using the principle of photo spectroscopy and it was found that the stability of nanoparticles to which surfactants and dispersants had been added was increased. The experiment with the diesel engine was carried out to evaluate the vibrations and noise by varying different loads (3, 6, 9, and 12 kgf) and injection pressures (200, 220, and 240 bar). The vibrations and noise intensity were reduced with B20 compared to normal diesel and a further reduction was observed by adding nanoparticles together with the dispersant. With increasing load, the RMS velocity and the RMS noise also increased, but these decreased with increasing injection pressure. The most favourable result for RMS velocity and RMS noise was B20+MoO3 75 ppm+ Dispersant 75ppm. At an injection pressure of 240 bar and a full load of 12 kgf, the RMS velocity was 0.568 m s-1 and 55.265 dB, which corresponds to an improvement of 28.76 % and 9.78 % respectively compared to conventional diesel for B20+MoO375ppm+ Dispersant 75ppm. Finally, the entire experimental data of 60 were predicted using various machine learning (ML) algorithms, such as Random Forest (RF), Decision Trees (DT), Artificial Neural Networks (ANNs), Support Vector Machines (SVM) and XG Boost and the predicted results correlated well with the experimental values. All algorithms have shown a good association, but XGBoost has shown a better correlation coefficient (R2). The R2 of each algorithm is in the range of 0.94–0.99, the MRE and RSME are also in the significant range for both RMS velocity and RMS noise.

Investigating the impact of ethanol and TiO2 on the performance and emission characteristics of diesel engines running on a blend of ethanol and castor biodiesel is the primary goal of this study. The nanoparticles of ethanol, biodiesel, and TiO2 diesel fuel were combined at several concentrations. Diesel, B10, B20, B30, B10E10T, B20E10T, B30E10T, B10E20T, B20E20T, and B30E20T were among the various fuels that were investigated. The physiochemical properties of all the sample fuels were assessed, including density, pour point, cloud point, fire point, flash point, and kinematic viscosity. Following this, other engine performance indicators, such as torque, power, and fuel-consumption, were examined. Studies were also carried out on the properties of emissions, including CO, CO2, HC, and NO. Peak braking power and engine torque were found for each fuel under investigation at around 2750 and 2500 rpm, respectively. The addition reduced the brake-specific fuel consumption for B10E20T by 7.41 % while increasing the braking engine's torque and power by 8.64 and 3.86 %, respectively, in compared to blends without the TiO2 additions. When compared to diesel, the exhaust emission data without the addition of TiO2 revealed a decrease in CO and HC emissions but an increase in CO2 and NO emissions. On the other hand, using ethanol blend reduced NO emissions. According to the overall findings, diesel engine performance, combustion characteristics, and exhaust gas emissions were enhanced averagely by 7.43 % when a certain ratio of ethanol, biodiesel, and TiO2 additives (B10E20 + 50 ppm) was used.

We report the fabrication of a novel spinel-type Pd₀.₁Cu₀.₉Co₂O₄ nano-flake material designed for Mizoroki-Heck and Suzuki coupling-cum-transesterification reactions. The Pd₀.₁Cu₀.₉Co₂O₄ material was synthesized using a simple co-precipitation method, and its crystalline phase and morphology were characterized through powder XRD, UV-Vis, FESEM, and EDX studies. This material demonstrated excellent catalytic activity in Mizoroki-Heck and Suzuki cross-coupling reactions, performed in the presence of a mild base (K₂CO₃), ethanol as the solvent, and microwave irradiation under ligand-free conditions. Notably, the Heck coupling of acrylic esters proceeded concurrently with transesterification using various alcohols as solvents. The catalyst exhibited remarkable stability under reaction conditions and could be recycled and reused up to ten times while maintaining its catalytic integrity.

This work presents a transposable adhesive in the form of reactive pressure sensitive adhesive (PSA) prepared from mixing acrylic copolymer and reactive components consisting of epoxy groups and acids, which exhibited different adhesion properties at different stages from a PSA to a semi-structural adhesive after activated by heat. In the first stage the adhesive showed well-balanced performances in terms of tack, peel and shear and the PSA behaved as a removable label with neat bond line. After activation the bonding strength was quickly increased due to the reaction between epoxide groups and carboxyl groups. Two acid-providers including glutaric acid and Carbomer and their effects on the PSAs and semi-structural adhesives were investigated. It is found that Carbomer, crosslinked poly (acrylate acid), played a significant role in static shear strength (>720 h), Tg (85 °C), temperature resistance (132 °C) and modulus. Beside the transformation from PSA to a semi-structural bond, the transposition concept further includes restoring bonding after cohesion failure, due to the self-healing property under trans-esterification mechanism through hydroxyl groups. The results showed that the bonding had been restored up to 95.74% of the original strength. How likely the self-healing behavior took place and how the composition of adhesives influenced the healing efficiency, is also discussed in detail.

One-step transesterification between ethylene carbonate (EC) and ethanol (EtOH) can effectively prevent the formation of azeotropes in the synthesis of diethyl carbonate (DEC) / ethyl methyl carbonate (EMC). However, owing to the influence of volume and electronic effects of EtOH molecules, the catalytic activity is insufficient. In this study, we propose an on-line synthesis technique for catalysts and prepare a unique heterogeneous alkali catalyst, PS-(NR3OH)EG. This technique simplifies the catalyst preparation process and protects it from exposure to water and carbon dioxide in the air. The active sites of PS-(NR3OH)EG are derived from the product ethylene glycol (EG). PS-(NR3OH)EG exhibits excellent catalytic performance in promoting EC and EtOH transesterification. The physicochemical properties of PS-(NR3OH)EG are analysed, and the reaction conditions are optimized. The results indicate that PS-(NR3OH)EG has superior catalytic activity and stability compared to the similar previously reported catalysts. Notably, after continuous reaction in a fixed-bed reactor for 500 h, PS-(NR3OH)EG maintain its initial catalytic activity. This study provides theoretical and experimental guidance for catalyst preparation and transesterification reaction process design.

Improvement in biofuel synthesis technology could facilitate widespread utilization of biodiesel, and an efficient operation in terms of cost. Catalyst enhancement through mineralization of waste biogenic material is vital for biodiesel production. In this study, biodiesel production was from waste cooking oil (WCO) using a bifunctional catalyst synthesized from waste eggshells and ferric sulfate. The CaO precursor developed from calcined eggshell at 800 °C for 3 h was impregnated with ferric sulfate at a ratio of 1:1. The Bifunctional catalyst synthesized was characterized using an X-ray diffractometer, scanning electron microscopy, Fourier transform infrared spectroscopy and energy-dispersive X-ray analysis. The bifunctional catalyst was applied in a one-pot reaction of WCO and methanol to produce biodiesel. The reaction was modeled using the Taguchi orthogonal array design to maximize biodiesel production. The heterogeneous catalyst contained Ca (20.7 %), Fe (18.5 %), S (4.5 %), and O (54.8 %). The identified crystalline phases are CaSO4/Fe2O3 and CaSO4.0.5H2O/Fe2O3. A maximum biodiesel yield of 89.94 wt% was observed under the operating conditions of methanol/oil molar of 5:1, time of 45 min, temperature of 70 °C, and catalyst amount of 4 wt%. The reusability of the catalyst was established for (four) 4 cycles without further treatment. The synthesized biodiesel met the standard specifications. Hence, the synthesized catalyst proved effective in the transesterification of oil with a moderately high free fatty acid, thereby the bifunctional catalyst could expedite biodiesel production from waste cooking oil, and this biofuel could serve as fuel in powering diesel engines.

Diversion of oil sources for biodiesel production has been gaining importance to meet the environmental concerns and energy demand. The free fatty acid (FFA) content of the feedstock is a significant factor in biodiesel production. The FFA values determine the complexity of the biodiesel production. Until date, an experimental procedure has been used to determine the FFA concentration of an oil source; this method is dependent on titration, which is a laborious process involving significant volumes of chemicals. Hence, in the present study, an attempt was made to develop a device for the identification of FFA of the oils. Waste cooking oil samples subjected to wide range of cooking conditions like cooking time, temperature, type of food are collected from different food outlets. Subsequently, the composition of oil samples and the variation in their quality were analysed using gas chromatography flame ionization detector (GC – FID). Biodiesel is prepared from the oil samples through transesterification and the impact of FFA and their respective methyl esters in the quality and properties have been investigated. The properties of biodiesel were determined as per ASTM standards. The study was further extended to correlate the properties of biodiesel with the composition of the oil from which it was derived. The analysis evidently proved the dependence of biodiesel properties on the FFA percentage and the composition of the oil. The results have been further substantiated with the performance and emission characteristics of internal combustion engine fuelled with the prepared biodiesel samples.

Biodiesel is generally obtained by transesterification and esterification of appropriate feedstocks facilitated by a catalyst. It has emerged to be one of the most potential alternatives for the conventional fuels gaining worldwide attention. Heterogeneous catalysts are usually preferred than homogeneous for biodiesel synthesis due to facile separation and insignificant soap formation. However, the separation still possesses difficulty leading to mass transfer hindrance. Therefore, these catalysts can be further modified using magnetic separation techniques to develop magnetically separable catalysts. The magnetic nanoparticles (MNPs) are notable appealing catalysts due to huge surface area, high activity, amicable functional groups and structures, adaptable properties, conformity in pore size, and facile separation have made them desirable catalyst carriers for biodiesel synthesis. The MNPs are modified via functionalization to construct magnetically recoverable heterogeneous nanocatalysts. Magnetic catalysts can be utilized as a befitting option for biodiesel synthesis as these are environmentally benign, highly reusable and economically viable. The current review article discusses different magnetic solid catalysts such as magnetic base, acid, biocatalysts and bifunctional of acid base catalysts for efficient biodiesel synthesis. The prime focus of this paper rest on the catalytic performances of various magnetically recoverable catalysts, mechanisms and recyclability for biodiesel production processes. The synthesis methods of magnetic heterogeneous base and acid nanocatalysts, magnetic properties, functionalization and their reciprocity on the catalytic activity are reviewed in this article.