Application In Biodiesel Production Research Articles

TiO2-ZnO based nano catalyst for biodiesel production: synthesis, characterisation, performance & emission study

Biodiesel (BD) production from bio-oil in the agriculture-based economy could minimise the energy dependency on fossil diesel (FD). Viscous properties and lower calorific value of BD restrict their direct application in the DE. These properties of BD can be enhanced by using advanced material (catalyst, adhesive etc) along with by modifying BD preparation processes. The present work deals with the synthesis and characterisation of nanocatalyst (TiO2-ZnO) and their application in BD production from waste cooking oil (WCO) via the transesterification process. Catalyst TiO2-ZnO was characterised by XRD, SEM and FTIR analysis. Catalyst TiO2-ZnO in a 4:1 mass ratio indicates the maximum BD yield. Maximum BD yield of 88% was noticed for molar methanol/WCO ratio – 1:1; catalyst dose – 2.5 g/l; reaction time – 120 min at reaction temperature -65°C respectively. The prepared BD was characterised by FTIR, GCMS, and HNMR analysis and compared their result with fossil diesel. Engine performance confirms that the 20% BD containing BM increases BSFC and EGT by 40 and 8.33% and decreases BTE by 14.26% in comparison with FD. But HC and CO emissions decreased by 50.27 and 57.44% respectively. While CO2 and O2 emissions are increased by 2.65 and 4.76% respectively. Highlights A maximum yield of 88% with TiO2-ZnO (4:1) mass ratio was obtained. BSFC and EGT increased by 40 and 8.33%. HC and CO emissions decreased by 50.27% and 57.44%.

Comparative Study of Immobilized Biolipasa-R for Second Generation Biodiesel Production from an Acid Oil.

The primary objective of this work is to develop a sustainable biocatalytic transesterification process for low-grade oils, aligning with EU green technology requirements for the shift to second generation biodiesel. Thus, we investigated the immobilization and subsequent application of the lipase Biolipasa-R on transesterification processes to produce fatty acid methyl esters (FAMEs) from both a sunflower oil and an acid oil which is a bioproduct of the biodiesel industry. The lipase was immobilized on biomaterials, such as diatomaceous earth, with a yield of 60 %, and commercial carriers such as methacrylic resins with a yield of 100 %. The enzyme demonstrated superior activity when immobilized on diatomaceous earth, particularly in reactions involving the acid oil, outperforming the benchmark enzyme Novozym® 435 (95.1 % and 35 % conversion respectively). This work highlights the potential of Biolipasa-R as a cost-effective and efficient biocatalyst for biodiesel production and emphasizes the environmental benefits of utilizing industrial byproducts and eco-friendly immobilization techniques. The findings suggest that Biolipasa-R is a promising candidate for industrial applications in biodiesel production, offering a sustainable solution for waste management and energy generation.

Turning Solid Waste into Catalysts: A Path for Environmental Solutions.

Waste, often overlooked, stands out as a prime source of valuable products, meeting the demand for natural resources. In the face of environmental challenges, this study explores the crucial role of waste-derived catalysts in sustainable practices, emphasizing the transformative potential of solid waste materials. Carbon-based catalysts sourced from agricultural, municipal, and industrial waste streams can be transformed into activated carbon, biochar, and hydrochar which are extensively used adsorbents. Furthermore, the paper also highlights the potential of transition metal-based catalysts derived from spent batteries, electronic waste, and industrial byproducts, showcasing their efficacy in environmental remediation processes. Calcium-based catalysts originating from food waste, including seashells, eggshells, bones, as well as industrial and construction waste also find an extensive application in biodiesel production, providing a comprehensive overview of their promising role in sustainable and eco-friendly practices. From mitigating pollutants to recovering valuable resources, waste-derived catalysts exhibit a versatile role in addressing waste management challenges and promoting resource sustainability. By transforming waste into valuable catalysts, this study champions a paradigm shift towards a more sustainable and resource-efficient future.

Investigation of Novel Transition Metal Loaded Hydrochar Catalyst Synthesized from Waste Biomass (Rice Husk) and Its Application in Biodiesel Production Using Waste Cooking Oil (WCO)

The decarbonization of transportation plays a crucial role in mitigating climate change, and biodiesel has emerged as a promising solution due to its renewable and eco-friendly nature. However, in order to maintain the momentum of the “green trend” and ensure energy security, an ecologically friendly pathway is important to produce efficient biodiesel. In this work, activated carbon (AC) obtained from rice husk (RH) is hydrothermally prepared and modified through cobalt transition metal for catalyst support for the transesterification process. The physicochemical characteristics of the synthesized catalysts are examined using XRD, FTIR, SEM and EDS, TGA, and BET, while the produced biodiesel is also characterized using Gas Chromatography and Mass Spectroscopy (GC-MS). To optimize the transesterification process, Fatty Acid Methyl Esters (FAME) are produced by the conversion of waste cooking oil. Response Surface Methodology (RSM) is used to validate temperature (75 °C), the methanol-to-oil molar ratio (1:9), catalyst weight percentage (2 wt.%), and retention time (52.5 min). The highest conversion rate of waste cooking oil (WCO) to biodiesel was recorded at 96.3% and tested as per American Society for Testing and Materials (ASTM) standards. Based on the results, it is clear that cobalt-loaded rice husk-based green catalyst (RHAC-Co) enhanced catalytic activity and yield for biodiesel production. Further research should focus on engine performance evaluation and scaling up of the catalyst by optimizing it for the industrial scale.

Enhancement of thermostability and expression level of Rasamsonia emersonii lipase in Pichia pastoris and its application in biodiesel production in a continuous flow reactor

The acidic lipase from Rasamsonia emersonii named LIPR has great potential for biodiesel synthesis due to its strong methanol tolerance. Nonetheless, the limited thermostability of LIPR and low expression level in Escherichia coli remain major obstacles to its use in biodiesel synthesis. To enhance the thermostability, the mutant LIPR harboring mutations A126C-P238C for the formation of a new disulfide bond and amino acid substitution D214L was obtained through rational design. To our delight, the thermostability of LIPR mutant was greatly improved. Moreover, a comprehensive optimization strategy, such as employing the Mss signal peptide, co-expressing the molecular chaperone protein disulfide isomerase (PDI), knocking out the vacuolar sorting receptor gene VPS10-01, and overexpressing the dihydroxyacetone synthase gene DAS2, was adopted to obtain the combination-optimized mutant Pichia pastoris strain GS54. Furthermore, the biodiesel synthetic capability with the mutant GS54-LIPR was verified and the production yield was 52.2 % after 24 h in a shake flask. Subsequently, a continuous flow system was adopted to increase the biodiesel yield to 73.6 % within 3 h, demonstrating its efficacy in enhancing enzyme biocatalysis. The engineered GS54-LIPR mutant lipase is an efficient and reusable biocatalyst for the sustained production of biodiesel in a continuous flow reaction.

Valorization of Bambusa striata shavings into functional superparamagnetic material and its application in biodiesel production: Response surface optimization, kinetics, thermodynamics and economic assessment

Herein, a novel highly porous biomass-based (Bambusa vulgaris striata) magnetic solid acid catalyst was developed for the first time via simultaneous activation and magnetization followed by acid functionalization. The sulfonated magnetic porous carbon was utilized as a catalyst for transesterifying Jatropha curcas oil (JCO) to biodiesel under microwave irradiation. The synthesized catalyst was extensively characterized using VSM, XRD, FTIR, SEM, EDS, TGA, XPS, Raman spectroscopy, and AFM techniques. Through Response Surface Methodology (RSM), a maximal biodiesel yield of 98.8 % was achieved over optimal optimal parametric states (catalyst loading 8 wt%, MOMR 24:1, 50 min, 80 °C). NMR confirmed JCO biodiesel formation with a FAME content of 98.04 %, and GCMS provided insight into its chemical composition. A pseudo-first-order kinetic study revealed an activation energy (Ea) of 28.734 kJ mol1. Thermodynamic analysis showed endothermic and non-spontaneous behavior with ΔH#, ΔS#, and ΔG# values of 25.928 kJ mol1, −0.193 kJ mol1 K1, and 94.251 kJ mol1, respectively. The catalyst displayed good reusability, easy recoverability, and stability, maintaining 75.4 % oil conversion even after ten consecutive cycles. Life cycle cost analysis (LCCA) estimates biodiesel production cost of $0.60 per liter, emphasizing high commercial viability.

Immobilization and characterization of hormone-sensitive lipase (HSL) from Glaciozyma antarctica

HSL-like esterase (GlaEst12) was isolated from the psychrophilic yeast Glaciozyma antarctica, and has a broad substrate specificity hence allowing hydrolysis of a wide range of ester molecules. This characteristic makes it relevant in a variety of industries, including food processing, pharmaceutical, and bioenergy. Immobilization of HSL-like esterase from G. antarctica (GlaEst12) was achieved through physical adsorption onto different types of supports such as Amicogen LKZ118, Amicogen LKZ518, Accurel MP1000, Seplite LXC621, and Seplite LX120. Among these, LKZ518 and LX120 exhibited a high immobilization rate (95 - 100 %), surpassing the other tested supports. Nonetheless, their recorded enzyme activity was notably lower when contrasted with the activity observed on LKZ118. While LKZ118 displayed a 50 % immobilization rate, it demonstrated remarkably high enzyme activity compared to the other supports. The optimal enzyme concentration for immobilization was determined to be 5 mg per gram of LKZ118 support. The immobilized lipase (GlaEst12_LKZ118) showed an optimum temperature et 60 °C similar to free GlaEst12 when tested using pNP-octanoate substrate. However, it showed a shift in pH optimum from pH 8 for free GlaEst12 to pH 9 for GlaEst12_LKZ118. GlaEst12_LKZ118 demonstrated prolonged stability at 60 °C, with a half-life of 180 min. Furthermore, it exhibited stability in the presence of methanol when treated at 50 °C, and increased activity in the presence of DMSO. Operational stability tests revealed that GlaEst12_LKZ118 maintained 65.5 % of its relative activity after 7 cycles, indicating its robust operational stability. In summary, the study demonstrated the successful immobilization of HSL lipase derived from G. antarctica using various supports and the immobilized enzyme showed promising activity levels for potential applications in biodiesel production and flavour ester synthesis.

L-cysteine-coated magnetite nanoparticles as a platform for enzymes immobilization: Amplifying biocatalytic activity of Candida antarctica Lipase A

This study presents the synthesis of magnetite nanoparticles coated with L-cysteine (Fe3O4@LC) and their subsequent utilization as a support matrix for the immobilization of Candida antarctica Lipase A (CALA). The immobilization process involved physical interactions and covalent bonding mediated by glutaraldehyde. Comprehensive characterization was conducted using techniques including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry (VSM), providing compelling evidence of a successful synthesis. Under optimized conditions, employing 1 mg of protein per gram of support, pH 7 in a 25 mM phosphate buffer, and a 5 h reaction at 25 °C, immobilization on glutaraldehyde-activated support achieved an impressive yield of 85.0 % ± 2.6, accompanied by a specific activity of 212.5 ± 1.3 U/g, outperforming the physical adsorption approach. Remarkably, the immobilized enzyme exhibited higher activity than the free enzyme at alkaline and acidic pH levels. Furthermore, thermal and pH inactivation studies revealed that the biocatalyst's half-life exceeded that of free CALA by more than 8 times at pH 10. These results underscore the potential of the Fe3O4@LC-GLU-CALA system as a robust biocatalytic matrix with promising applications in biodiesel production, ester synthesis, and pharmaceutical manufacturing.

Carbonaceous catalysts (biochar and activated carbon) from agricultural residues and their application in production of biodiesel: A review

Carbonaceous catalysts obtained from agricultural residue could have potential in the production of biofuels such as biodiesel. This review paper discusses the preparation conditions (temperature, heating rate, hold time, inert gas flow rate, etc play key roles in development of textural characteristics of the catalysts) and functionalization methods of biochar and activated carbon derived from agricultural residues and their application to produce biodiesel. Research works reported in achieving maximum yield of biodiesel in terms of variable precursors, alcohol-to-oil ratio, reaction time and temperatures have been profoundly tabulated. Effect of textural properties of the biochar and activated carbon (such as surface area, total pore volume, average pore size, and functional group attached with the catalyst) on the biodiesel yield are examined. Studies on Regeneration and reusing of the spent catalysts are carefully inspected. The economic evaluation studies for the biochar and activated carbon and the applications of these for biodiesel production are scrutinized. Finally, the strategies to increase biomass and catalyst productivity, future prospect and research directions to enhance biofuel/biodiesel production and for the development of biochar and activated carbon from agricultural residues for sustainable biodiesel production is suggested.

Multi-walled carbon nanotubes as lipase carriers for organic synthesis: Current trends and recent update

Lipase-catalyzed organic reactions have been widely practiced in the past three decades. Especially interesting are insoluble/immobilized forms due to providing a possibility of facile use and recyclability, thus reducing process costs, and making the procedure more environmentally friendly. Carbon-based supports have been extensively exploited for this purpose, because of neutral and biodegradable nature and thermal and chemical stability. Their high specific surface area, characteristic surface morphology and lower mass transfer resistances play a vital role in the performance of the attached enzyme. This review paper presents an overview of the main aspects of lipase immobilized on multi-walled carbon nanotubes (MWCNTs). Moreover, different immobilization strategies to achieve a biocatalyst with improved performances are discussed. Furthermore, as lipases are considered to have high commercial worth for synthesis of valuable organic molecules, the second part of the paper is dedicated to the overview of the most important industrial sectors in which these nanobiocatalysts have been used. In specific, applications in biodiesel production, flavour ester synthesis and racemization are summarize

The catalytic effect of calcium oxide and magnetite loading on magnetically supported calcium oxide-zeolite catalyst for biodiesel production from used cooking oil

This research focuses on developing a magnetically supported catalyst for efficient transesterification reaction of used cooking oil (UCO). The catalyst consists of calcium oxide (CaO) and ZSM-5 zeolite, which were synthesized using waste chicken eggshell and rice husk. Meanwhile, magnetite (Fe3O4) was used as a magnetic component. Various magnetic zeolite-supported CaO catalysts (CaZ/Fe) were prepared with different amounts of CaO (10, 30, 50, and 80 wt% of zeolite) and Fe3O4 (1:0.5, 1:1, 1:1.5 and 1:2 of CaO-zeolite:Fe3O4 ratio). The results identified the 50CaZ/0.5Fe catalyst as the most effective. The catalyst displayed a high surface area, strong basicity, and ideal morphology, thus contributing to a higher biodiesel yield of 91%. The recovery rate of the 50CaZ/0.5Fe catalyst was 88%, suggesting minimal loss and easy catalyst separation post-reaction using an external magnetic field. It also displayed superior stability, obtaining 85% biodiesel yield after 4 uses. The activation energy calculated in the kinetic study was 14.085 kJ/mol. Moreover, the properties of the synthesized biodiesel met the standards set by the ASTM D6751. Overall, the 50CaZ/0.5Fe catalyst with good magnetic behaviour and exhibits excellent catalytic activity suggested that this catalyst is promising for application in biodiesel production.

Preparation of rare earth modified clay-based solid acid catalysts and their application for biodiesel production from soybean oil

ABSTRACT In this study, catalysts of SO4 2-/ZrO2-La2O3-Hangjin 2# clay (SZLa-HJ) and SO4 2-/ZrO2-CeO2-Hangjin 2# clay (SZCe-HJ) were prepared with La and Ce as cocatalysts respectively. The activity of the catalysts was evaluated based on the conversion of biodiesel, while examining the effects of rare earth doping, sulfuric acid concentration, and calcination temperature. Central composite design optimized the preparation procedure for SZLa-HJ and SZCe-HJ. NH3-TPD, Py-FTIR, EDS, TG, DAT, SEM, XRD and XPS techniques were employed to describe it. The results showed that adding La or Ce to SO4 2-/ZrO2 Hangjin 2# clay effectively controlled the distribution of acid sites by increasing both Bronsted and Lewis acid sites in a way that maintained more Lewis acid sites in the catalyst; this was favorable for transesterification reaction.

MoO3/ironepinelium catalyst supported on ornamental rock residues with potential application in biodiesel production

The search for environmentally correct fuels has been gaining momentum/prominence in scientific research, for example, using oils or fats of animal/vegetable origin and commercial/residual oils. These oils consist primarily of free fatty acids with high energy power and can be converted into fatty acid esters (biodiesel) using highly efficient and recyclable heterogeneous catalysts. Among the heterogeneous catalysts most used in the conversion of biodiesel, two are worth mentioning: MoO3 and ferrospinels. The first is because it contains in its structure, especially the orthorhombic, acidic active sites of Lewis and Brönsted-Lowry, and the second is because they have high specific surface areas and adequate magnetic characteristics that allow the recovery of the medium. Another interesting point is the use of residues for catalysis that has been highlighted, as they are materials that contain metals such as Fe, K, Si, Mg, Na, and Ti in their composition, which accelerate reactions. Thus, in this sense, this article proposes to carry out a bibliographical survey of the literature in experimental scientific papers and published reviews on the use of MoO3 and ferrospinels as heterogeneous catalysts supported on waste from cut ornamental rocks (granite/marble) for the production of biodiesel, which is the core of this search, on the online data platforms Science Direct (Elsevier) and Web of Science covering the period from 2016 to April 2023, using the Start software (State of the Art through Systematic Review). The results revealed a quantitative of 223 articles in general, in which 62 were accepted, and 161 were rejected. While in the review extraction stage, 22 papers were accepted, and 40 were rejected. In addition, the review revealed that most of the catalysts and catalytic supports used for the production of biodiesel with oils are oxides, nothing specifically informing the use of waste from cuts of ornamental rocks (granite/marble) as a host material (support) for the catalysts MoO3 and ferrospinels aiming the production of biodiesel. Therefore, meaning that it is not possible to use this type of residue as a support for catalysts, but rather that there may be a lack of research investigating this application.

SOLVOTHERMAL SYNTHESIS AND CHARACTERIZATION OF TEREPHTHALIC ACID-BASED METAL-ORGANIC FRAMEWORKS AND THEIR CATALYTIC APPLICATION IN BIODIESEL PRODUCTION

Metal-Organic Frameworks (MOFs) are a class of porous crystalline materials, consisting of metal ions or nodes linked with organic ligands. The study was aimed at solvothermal synthesis and characterization of terephthalic acid-based Metal-Organic Frameworks and their catalytic application in biodiesel production. Three MOFs of Cu-, Fe-, and Cr-based were solvothermally synthesized, characterized and applied as catalysts in biodiesel production using ethanol and oil extracted from Yellow Oleander seeds. The MOFs were synthesized using terephthalic acid as the linker and copper (II), iron (III) and chromium (III) nitrates as metal ion sources. Each of the synthesized MOFs showed high melting point exceeding 360 oC. Microscopic view and powder X- ray diffraction analysis indicated Cu-MOF to be crystalline with numerous sharp peaks while those for Fe- and Cr-MOFs were amorphous. A comparison of the FT-IR spectra of the ligand and those of the MOFs confirmed the presence of the ligand in the synthesized MOFs. In the absence of a catalyst, the transesterification was not achieved. However, in the presence of the more crystalline Cu-MOF as catalyst resulted to high yield (83.33%) and in a shorter time compared to the less crystalline Fe- (33.33%) and Cr- (25.00%) MOFs. Thus, catalytic ability of the MOFs were in the order: Cu-MOF > Fe-MOF > Cr-MOF. Hence MOFs especially Cu-MOFs can be applied as catalyst in biodiesel production. Further studies and characterization (single X-ray diffraction) should be done for proper elucidation of the crystal structure of the MOFs.

Comprehensive Treatment Strategy for Banana Inflorescence Bract to Synthesize Biodiesel and Bioethanol Through Fungal Biorefinery

Banana inflorescence bract (BIB), an agro-waste is sporadically explored for second-generation biofuel production in spite of having considerable holocellulosic composition (cellulose-35.56%, w/w; hemicellulose-22.41%, w/w). In this study, an attempt has been made to utilize this substrate for fermentable sugars (pentose-C5 and hexose-C6) extraction which were employed for the co-production of microbial lipids and ethanol using Rhodosporidium toruloides NCIM 3547 and Saccharomyces cerevisiae respectively. Since, a considerable amount of lignin (8.78%, w/w) is present in BIB, a hybrid pretreatment and carbohydrate hydrolysis through microwave (160 W) assisted mild H2SO4 acid 2.5% (v/v) was adopted. The resultant liquor contains holocellulosic sugars (C5 and C6 sugars), out of which xylose (10.40 ± 0.49 g/L) and glucose (51.48 ± 1.14 g/L). Hence, it was used as the growth medium for R. toruloides to produce lipids i.e., single cell oil (SCO). The maximum lipid content was found to be 44.89 ± 1.25 (%, w/w) containing total saturated fatty acids of 89.07% which justifies its potential application in biodiesel production. On the other hand, the pretreated solid fraction containing cellulose was saccharified using cellulolytic enzyme produced by Aspergillus sp. with saccharification (%) of 69.99 ± 0.30 (%, v/w) and yield of 27.22 ± 0.33 g/L of reducing sugar. This enzymatic hydrolysate was used for ethanol production by Saccharomyces cerevisiae resulting in an ethanol yield of 12.70 ± 0.09 g/L and productivity of 0.132 g/L/h. Based on this outcome, a sustainable route for agro-waste management of BIB was laid by favouring the integrated production of biodiesel and bioethanol towards a biorefinery approach. Exploration and utilization of an agro-waste, banana inflorescence bract is established as a potent feedstock for the co-production of single cell oil and bioethanol is reported for the first time. Microwave-assisted mild acid pretreatment was performed for effective delignification and hydrolysis of holocellulosic components. The resultant liquid hydrolysate consisting of lignin degradatory compounds, pentose (xylose) and hexose (glucose) sugars was used as a growth medium for producing single cell oil, proving its potential application in biodiesel production. Further, the pretreated solid cellulosic fraction was saccharified using crude cellulolytic enzymes and an enzymatic hydrolysate was used for the production of bioethanol through two different fermentative strategies. This study reveals that banana inflorescence bract could act as suitable biomass towards the biorefinery approach. Its complete utilization paved the way for agro-waste management that is not in existence so far according to the authors’ knowledge

Isolation, Purification, and production of lipase from Bacillus subtilis isolated from food processing wastes and its application in biodiesel production

Isolation, Purification, and production of lipase from Bacillus subtilis isolated from food processing wastes and its application in biodiesel production

Plant-Biomass-Derived Carbon Materials as Catalyst Support, A Brief Review

Carbon materials are widely used in catalysis as effective catalyst supports. Carbon supports can be produced from coal, organic precursors, biomass, and polymer wastes. Biomass is one of the promising sources used to produce carbon-based materials with a high surface area and a hierarchical structure. In this review, we briefly discuss the methods of biomass-derived carbon supported catalyst preparation and their application in biodiesel production, organic synthesis reactions, and electrocatalysis.

Scale-Up Lipase Production and Development of Methanol Tolerant Whole-Cell Biocatalyst from Magnusiomyces spicifer SPB2 in Stirred-Tank Bioreactor and Its Application for Biodiesel Production

This study aimed to economically develop the yeast whole-cell biocatalyst from the lipase-secreting Magnusiomyces spicifer SPB2 to serve green biodiesel production. The scaled-up productions of lipases were optimized using a 5-L stirred-tank bioreactor. The maximum extracellular lipase and cell-bound lipase (CBL) yields of 1189.65 U/L and 5603.74 U/L were achieved at 24 h and 60 h, respectively, in the modified IMY medium (pH 5.0) containing 2% of soybean oil as a carbon source and 0.2% Gum Arabic as an emulsifying agent. The optimized cultivation was initiated with an inoculum size of 1 × 107 cells/mL and conducted under an aeration rate of 0.75 vvm with an agitation speed of 400 rpm. The obtained whole-cell biocatalyst of M. spicifer SPB2 was applied to catalyze the transesterification reaction using palm oil and methanol as substrates. The greatest yield of 97.93% fatty acid methyl ester (FAME) was reached at 72 h using a palm oil/methanol ratio of 1:7, indicating high methanol stability of the biocatalyst. Moreover, substrate homogenization accelerated the reaction to achieve FAME production of 97.01% at 48 h and remained stable afterwards. Without homogenization, the highest FAME of 98.20% was obtained at 60 h. The whole-cell biocatalyst prepared from lipase-secreting M. spicifer SPB2 at an up-scaled level greatly enhanced efficiency and feasibility for commercial biodiesel production through a green conversion process.

INVESTIGATION OF THE POTENTIAL OF WASTE BONES AS A CATALYST IN BIOFUEL PRODUCTION

It has recently come to light that inappropriate waste management (particularly of animal bones) is a major contributor to environmental degradation on a global scale. Instead, it would be extremely beneficial to the economy if the bioeconomy civilization could find novel applications for these discards. Biodiesel’s output can be put to good use as a heterogeneous catalyst in the effective recycling of animal bone. Ca-based catalysts produced from discarded bones, have been extensively studied in the transesterification reaction due to their high catalytic activity and abundant feedstock. Calcium oxide, a common mineral, can be used to create heterogeneous catalysts (in the form of discarded bones). However, process improvements are required to make calcium oxide-based catalysts suitable for industrial use. This research summarizes the sources of waste animal bones, provides context for the recent advances in the development of various Ca-based catalysts derived from waste animal bones, characterized a calcium oxide-based catalyst derived from waste animal bones, and details its application in biodiesel production. In this work, waste bones were modified by calcination at 9500C for 3h. The catalyst was analyzed using scanning electron microscopy (SEM) for its morphological structure, Fourier transform infrared spectroscopy (FTIR), for its functional group, X-ray fluorescence (XRF), for its elemental composition, thermogravimetric analysis (TGA), for thermal stability and Brunauer Emmett Teller (BET) surface area analysis. Overall, raw sample was found to have no effect on the waste bone, while high temperature calcination greatly affected the pore size, surface area, composition, and thermal decomposition profile of the waste bone sample. According to the study’s findings, used animal bones can be used to create catalysts that are appropriate for trans-esterifying a variety of oil sources into high-quality biodiesel. This increases the total energy and atom-efficiency of both conventional and new chemical processes while also making the system more cost-effective and ecologically benign. This discovery will encourage scientists to look into possible wastes of bones and pave the way for a more cost-effective and ecologically friendly way to make biodiesel and should also continue to be evaluated for the likelihood of their use in the commercial sector.

MOF-derived hierarchically ordered porous carbon for the immobilization of Eversa® Transform 2.0 and its post-immobilization hydrophobization in biodiesel production

MOF-derived carbon has extraordinary advantages including highly ordered morphology inherited from MOFs and improved chemical stability arising from its carbon nature, which may be a promising immobilized enzyme carrier. Herein, we prepared two MOF-derived carbon materials of different structures for the immobilization of lipase from Eversa® Transform 2.0 and systematically evaluated their application potential in biodiesel production system. Compared with C-C (derived from conventional microporous ZIF-8), 3DOM-C (derived from 3D ordered macro-microporous ZIF-8) exhibited superior immobilization performance with an 145.1% increase in enzyme loading and an 130.2% increase in activity. Moreover, lipase immobilized on 3DOM-C (3DOM-C@TLL) showed better catalytic performance than C-C@TLL, with faster conversion rate in lipase-mediated biodiesel production. Remarkably, the higher surface hydrophobicity of the 3DOM-C@TLL was proved to be the key factor in its improved catalytic performance. Meanwhile, we found that the affinity between immobilized enzyme molecules and water significantly weakened the hydrophobicity of C-C@TLL and 3DOM-C@TLL, which could be of adverse effect on their application in biodiesel production. To enhance the hydrophobicity of immobilized lipase biocatalyst, a facile post-immobilization hydrophobic modification strategy was proposed by coating the 3DOM-C@TLL with polydimethylsiloxane (PDMS). The as obtained super hydrophobic 3DOM-C@TLL@PDMS biocatalyst showed excellent catalytic performance in biodiesel production, with a much higher initial reaction rate, which was 3.3 folds of that catalyzed by C-C@TLL, and 1.8 folds of that catalyzed by 3DOM-C@TLL. This work shed light on the great potential of constructing MOF-derived hierarchically ordered porous carbon for enzyme immobilization in extensive practical applications.