Impregnation of CaO from Eggshell Waste with Magnetite as a Solid Catalyst (Fe3O4/CaO) for Transesterification of Palm Oil Off-Grade

Novel iron sand-derived α-Fe2O3/CaO2 bifunctional catalyst for waste cooking oil-based biodiesel production

The main aim of this work was to develop a heterogeneous Fe2O3/CaO2 bifunctional catalyst prepared from iron sand and 3 different CaO2 sources (CaCO3, Ca (OH)2, and limestone) using wet impregnation and calcination methods for biodiesel production. The effects of different CaO2 sources and Fe/Ca ratio in the catalyst were investigated to provide insight into the catalyst character and biodiesel yield. X-ray diffraction, X-ray fluorescence, and scanning electron microscopy analyses were used to characterize the catalyst. CaCO3 was concluded as the best CaO2 source, while the best Fe/Ca configuration was found to be 1:4, giving the highest biodiesel yield (97.0401%) with no diglycerides. Greater addition of Fe loading would result in an amorphous structure, and all catalysts were relatively crystalline. Fe was concluded to favor the esterification reaction and biodiesel formation, while CaO2 was seen to favor the transesterification reaction and fatty acid methyl ester (FAME) formation. The catalyst mechanism was also established in this study, where esterification of free fatty acid (FFA) and glycerol took place on the acid site to produce diglyceride and transesterification of triglyceride by methanol occurred on the basic site.

Synthesis and characterization of barium doped CaO heterogeneous nanocatalyst for the production of biodiesel from Catharanthus roseus seeds: Kinetics, optimization and performance evaluation

The exploitation of petroleum derivatives to meet the energy demands of the cutting edge is thought of as impractical because of asset shortage. The current necessitates that the world community improves future energy sources by developing sustainable, ecofriendly alternatives. In this work, biodiesel is produced through the transesterification of Catharanthus roseus seed oil with a barium-doped CaO heterogeneous nanocatalyst. The catalyst characterization is assessed using FTIR, GC-FID, EDAX, XRD, and SEM. The optimum conditions of time (70 min), temperature (58 °C), the molar ratio of methanol: oil is 15:1, and catalyst load (4% w/w) resulted in a conversion of the maximum biodiesel yield of 91.83%. Finally, by using Catharanthus roseus as a feedstock, the low optimal reaction conditions contribute to the development of the economic impact of biodiesel synthesis. Biodiesel blend (B20) containing barium-doped CaO nanoparticles showed better combustion engine performance and lower emissions than fossil fuels.

Synthesis of Carbide Lime Waste Derived Base Catalyst (KF/CLW-Fe3O4) for Methyl Ester Production: An Optimization Study

In this paper, solid base catalyst KF/CLW-Fe3O4 was prepared from carbide lime waste, primarily calcium hydroxide with tiny amounts of carbonate and; the catalyst was used in the optimization study on the methyl ester production. The new strong base catalyst was synthesized by chemical impregnation. This catalyst was characterized by Hammett indicator analysis, Brunauer, Emmett, and Teller (BET), scanning electron microscope (SEM), X-ray diffraction (XRD) and temperature-programmed desorption (TPD) of carbon dioxide. The catalyst was further used to catalyzed the transesterification reaction to produce methyl ester. Taguchi method was used to assess the impact of catalyst at different intervals of reaction parameters, including reaction time, methanol to oil ratio, and catalyst loading. A mixed level of orthogonal array design with L9, analysis of variance (ANOVA) and signal to noise ratio were used to determine parameters that significantly impact the palm oil transesterification reaction. High methyl ester conversion was attained, and the catalyst can be easily separated and reused. KF/CLW-Fe3O4 has great potential to be used to produce methyl ester because of its high catalytic activity and environmental friendliness. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Synthesis of Magnetic Base Catalyst from Industrial Waste for Transesterification of Palm Oil

Industrial waste is produced in large amounts annually; without proper planning, the waste might cause a serious threat to the environment. Hence, an industrial waste-based heterogeneous magnetic catalyst was synthesized using carbide lime waste (CLW) as raw material for biodiesel production via transesterification of palm oil. The catalyst was successfully synthesized by the one-step impregnation method and calcination at 600 °C. The synthesized catalyst, C-CLW/g-Fe2O3, was characterized by temperature-programmed desorption of carbon dioxide (CO2-TPD), scanning electron microscopy (SEM), electron dispersive X-ray spectroscopy (EDX), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FT-IR). The catalyst has a specific surface area of 18.54 m2/g and high basicity of 3,637.20 µmol/g. The catalytic performance shows that the optimum reaction conditions are 6 wt% catalyst loading, 12:1 methanol to oil molar ratio with the reaction time of 3 h at 60 °C to produce 90.5% biodiesel yield. The catalyst exhibits good catalytic activity and magnetism, indicating that the CLW can be a potential raw material for catalyst preparation and application in the biodiesel industry. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Polyunsaturated Fatty Acid Fractionation from Crude Palm Oil (CPO)

Biodiesel is a fuel derived from vegetable oil. One of the vegetable oils that can be used in the manufacture of biodiesel is Crude Palm Oil (CPO). High-quality biodiesel must have a low iodine number and a high oxidation stability. This can be achieved if CPO does not contain polyunsaturated fatty acids (PUFA). It follows that in order to produce high-quality biodiesel, palm oil that contains high saturated fatty acids but that does not contain PUFA is needed. Therefore, it is necessary to fractionate PUFA with saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). The purpose of this study was to separate PUFA in the form of linoleic acid from CPO and to determine the best conditions in the separation process to produce fatty acids with low iodine numbers. Fractionation was carried out at temperatures of 30 °C and 35 °C, with an extraction time of 3 h and 4 h, and with ratios of CPO and solvent of 1:2 and 1:3 (v/v). The solvents used were n-heptane and DMSO (dimethyl sulfoxide). The results showed that linoleic acid could be separated from CPO using the fractionation method with the best conditions at a temperature of 35 °C, an extraction time of 4 h, a ratio of CPO and solvent of 1:3, an iodine number of 40.78766, and an oxidation stability of 19.03593 h. GC-MS analysis proved that the fractionated CPO did not contain linoleic acid. The lower the iodine number was, the higher the oxidation stability was.

Synthesis and Characterization of Novel Fe3O4/PVA/Eggshell Hybrid Nanocomposite for Photodegradation and Antibacterial Activity

In the 21st century, hybrid nanocomposites were widely used in bioelectronic, biosensing, photocatalytic, and biomedical applications. In the present study, we fabricated a novel Fe3O4/PVA/Eggshell hybrid nanocomposite and physicochemically characterized it using powder XRD, EDS, FTIR, VSM, and HR-TEM analysis. The XRD spectrum revealed the crystalline and FCC configuration of Fe3O4 NPs with average crystal size of 16.28 nm, and the HRTEM image indicates the prepared hybrid nanocomposite is of spherical shape with less agglomeration. This hybrid nanocomposite showed a significant photodegradation property in degrading organic pollutants such as congo red and crystal violet dyes under the sunlight irradiation. In addition, the hybrid nanocomposite also displayed a potent antibacterial property against different Gram +ve and Gram −ve bacterial pathogens. This study provides a significant example in the overview of fabrication of cost effectively, eco-friendly, and multiple-application hybrid nanocomposites through eggshell membrane fibers.

Biodiesel Production from Waste Cooking Oil Catalyzed by a Bifunctional Catalyst

The objective of this study was to prepare bifunctional catalysts based on iron and CaO and test them in the biodiesel production using waste cooking oil (WCO) as feedstock. Two iron precursors were studied, Fe₂O₃ and Fe(NO₃)₃·9H₂O. The identified crystalline phases were Ca₂Fe₂O₅ and CaFeO₃. Surface morphology and textural properties (distribution of active species, specific surface area, size, and pore volume) were also analyzed. Additionally, thermal stability was studied and 800 °C was established as the optimum calcination temperature. The density of both acidic and basic sites was higher with the catalyst prepared with Fe₂O₃ than with that prepared with Fe(NO₃)₃·9H₂O. The latter, however, leads to reach equilibrium in half of the time than with the former. This was ascribed to the ratio of acidic to basic sites, which is higher with the catalyst prepared with the precursor salt. This ratio not only affects the overall cost of the process by affecting the time at which equilibrium is reached but also by dictating the methanol/oil molar ratio at which the equilibrium is reached sooner. The prepared bifunctional catalyst allowed us to produce biodiesel with 90% of methyl ester content at atmospheric pressure, reaction temperature of 60 °C, reaction time of 2 h, with 12:1 M ratio of methanol/WCO, 10 wt % of Fe over CaO, and a catalyst loading of 5 wt %. This catalyst can be used at least 3 times. The so-obtained biodiesel met the European norm EN-14214 regarding viscosity and density.

Bio-Derived Catalysts: A Current Trend of Catalysts Used in Biodiesel Production

Biodiesel is a promising alternative to fossil fuels and mainly produced from oils/fat through the (trans)esterification process. To enhance the reaction efficiency and simplify the production process, various catalysts have been introduced for biodiesel synthesis. Recently, the use of bio-derived catalysts has attracted more interest due to their high catalytic activity and ecofriendly properties. These catalysts include alkali catalysts, acid catalysts, and enzymes (biocatalysts), which are (bio)synthesized from various natural sources. This review summarizes the latest findings on these bio-derived catalysts, as well as their source and catalytic activity. The advantages and disadvantages of these catalysts are also discussed. These bio-based catalysts show a promising future and can be further used as a renewable catalyst for sustainable biodiesel production.

Biosynthesized magnetite nanoparticles as an environmental opulence and sustainable wastewater treatment

This review emphasizes the win-win one-pot valorization process of different waste biomass that composed of many biological macromolecules (e.g. polysaccharides, polyphenols, carbohydrates, lipids, enzymes, proteins, etc.) and other biomolecules (e.g. alkaloids, terpenoids, tannins, phenolics, carotenoids, amino acids, sugars, vitamins, etc.) into biofunctionalized magnetite (Fe₃O₄) nanoparticles (BMNPs). It illustrates the sustainable recruitment of microbial intra- and extra-cellular metabolites, proteins, and/or enzymes in the biosynthesis of BMNPs. It elucidates the environmental affluence of such sustainable, cost-effective, and ecofriendly BMNPs as an antimicrobial agent for water disinfection, photo-degrader, and adsorbent for different xenobiotics, organic and inorganic water pollutants. It confers the future environmental aspects of BMNPs in biofuels production from lipids and lignocellulosic wastes, biosensors manufacturing and bio-upgrading of petroleum fractions, etc. It discusses the circular economy, challenges, and opportunities for scaling up the zero-waste green synthesis of MNPs. Nevertheless, imminent investigations are still needed to elucidate the exact rule of biological macro- and micro- molecules in BMNPs synthesis and mechanisms involved in its microbicidal and photodegradation activities. Accentuated researches are more required on the toxicity and/or biosafety of the green synthesized BMNPs to humans and other non-target organisms to ensure its eco-safety upon environmental applications.

Progress on Modified Calcium Oxide Derived Waste-Shell Catalysts for Biodiesel Production

The dwindling of global petroleum deposits and worsening environmental issues have triggered researchers to find an alternative energy such as biodiesel. Biodiesel can be produced via transesterification of vegetable oil or animal fat with alcohol in the presence of a catalyst. A heterogeneous catalyst at an economical price has been studied widely for biodiesel production. It was noted that various types of natural waste shell are a potential calcium resource for generation of bio-based CaO, with comparable chemical characteristics, that greatly enhance the transesterification activity. However, CaO catalyzed transesterification is limited in its stability and studies have shown deterioration of catalytic reactivity when the catalyst is reused for several cycles. For this reason, different approaches are reviewed in the present study, which focuses on modification of waste-shell derived CaO based catalyst with the aim of better transesterification reactivity and high reusability of the catalyst for biodiesel production. The catalyst stability and leaching profile of the modified waste shell derived CaO is discussed. In addition, a critical discussion of the structure, composition of the waste shell, mechanism of CaO catalyzed reaction, recent progress in biodiesel reactor systems and challenges in the industrial sector are also included in this review.

Optimisation of biodiesel production from dairy effluent scum using calcined egg shell as a transesterification catalyst

The production of biodiesel from dairy effluent scum using calcined egg shell as the transesterification catalyst has been explored. Eggshell powder was calcined at 900 °C for 3 h and used as catalyst. The influence of methanol-oil molar ratio, catalyst concentration and reaction temperature were studied using Response Surface Methodology employing a Central Composite Rotatable Design. An empirical model that relates the yield of biodiesel to the studied factors was obtained. The model has high statistical significance at 95% confidence interval with R2 and adjusted R2 values of 96.31% and 95.75% respectively. Results showed that among the three studied factors, the methanol-oil molar ratio had the greatest contribution to the yield of dairy effluent scum derived biodiesel followed by reaction temperature and finally, the catalyst concentration. Significant interaction effects were also present between methanol-oil ratio and catalyst, catalyst and reaction temperature and methanol-oil ratio and reaction temperature. Accordingly, the optimal variable settings were 14.355:1 methanol-oil molar ratio, 3.09% catalyst loading by weight of pre-treated dairy scum oil and 55.20°C reaction temperature; with a corresponding yield of 92.72%.

Modification and characterization of chicken eggshell for possible catalytic applications

Researchers have shown considerable interest in finding a sustainable, low cost, and readily available substitute for the commercial calcium oxide (CaO) catalyst. In this work, raw chicken eggshell was modified by boiling and calcination at 900 °C for 3 h. The x-ray diffraction characterization revealed that while the proportion of CaCO₃ in the raw and boiled samples was found to be 79.3 % and 99.2 % respectively, the CaCO₃ had been converted to 63.8 % CaO and CO₂ in the calcined sample. This was due to the thermal decomposition during calcination. The outcome of the infrared spectroscopy showed that the raw and boiled chicken eggshell presented a similar absorption profile with peaks at 1 394 cm^-1, 873 cm^-1, and 712 cm^-1, which were as a result of the presence of asymmetric stretch, out-of-plane bend, and in-plane bend vibration modes. The major peaks presented by the calcined sample at 3642 cm^-1 can be attributed to the OAH stretching vibration and bending hydroxyl groups present in Ca(OH)₂. The Brunauer-Emmett-Teller surface areas for the raw, boiled and calcined chicken eggshell were found to be 2.33 m²/g, 3.26 m²/g, and 4.6 m²/g respectively, indicating increased catalytic activity of the calcined sample. Overall, boiling was found to have a negligible effect on the chicken eggshell, while high-temperature calcination greatly affected the pore size, surface area, composition, and thermal decomposition profile of the chicken eggshell sample.

Recycled eggshells as precursors for iron-impregnated calcium oxide catalysts for partial oxidation of methane

There is a significant interest in converting eggshells into value-added products. Therefore, the goal of this research is to synthesize and study iron-impregnated eggshells as a catalyst for partial oxidation of methane. The objectives of this research were to test the effects of iron loading, flow rate, oxygen concentration, and temperature on methane oxidation. The catalysts were synthesized using ferric chloride hexahydrate at various loadings and tested in a heated stainless-steel reactor under different experimental conditions. The reaction products included C2–C7 hydrocarbons, carbon monoxide, and carbon dioxide depending on the reaction conditions. Results indicated that iron loading beyond 5 wt% caused a decrease in methane conversion. A decrease in oxygen concentration enhanced methane conversion with a substantial drop in the production of CO2. Besides, an increase in temperature resulted in a decrease in methane conversion with a simultaneous increase in the production of CO2 via overoxidation. The reusability experiments indicated that the catalyst was active for four reaction cycles. Our results indicate that eggshells can be used as catalyst support for methane partial oxidation and can simultaneously solve the waste disposal problems faced by the poultry industry.

Composite Catalyst of Palm Mill Fly Ash-Supported Calcium Oxide Obtained from Eggshells for Transesterification of Off-Grade Palm Oil

This research was designed to synthesize a composite catalyst of palm oil fly ash-impregnated calcium oxide prepared from eggshell waste. Several preparation conditions, such as temperature and time applied to calcination and dehydration processes, were investigated. As a result, the optimum temperature and the length of time of calcination were 900 °C and 3 h, respectively. Meanwhile, the dehydration process was performed optimally at 600 °C for 3 h. The X-ray diffraction (XRD) results indicate that the obtained catalyst mostly contained calcium oxide compounds (CaO and Ca(OH)2) and minor impurities of silica oxides (SiO2 and Ca2SiO4), with a catalyst-specific surface area of 30.24 m2/g. Regarding its catalytic performance, the composite catalyst proved successful for prospective application the in transesterification of palm oil off-grade, resulting in methyl palmitate and methyl oleate, which are two biodiesel compounds.