TGA Result Research Articles

Exploring the functional properties and utilisation potential of mollusca shell by-products through an interdisciplinary approach

Molluscan shellfish aquaculture contributes to 42.6% of global aquaculture production. With a continued increase in shellfish production, disposal of shell waste during processing is emerging as an environmental and financial concern. Whilst major commercial species such as Crassostrea spp. has been extensively investigated on usage of its shell, with information that are crucial for valorisation, e.g. safety and crystal polymorphs, evaluated. There is currently little understanding of utilisation opportunities of shell in several uprising Australian commercially harvested species including Akoya Oyster (Pinctada fucata), Roe’s Abalone (Haliotis roei) and Greenlip Abalone (Haliotis levigata), making it challenging to identify ideal usages based on evidence-based information. Therefore, in this study, an interdisciplinary approach was employed to characterise the shells, and thereafter suggest some potential utilisation opportunities. This characterisation included crude mineral content, elemental profiling and food safety evaluation. As well, physical, chemical, and thermal stability of the shell products was assessed. TGA result suggests that all shells investigated have high thermal stability, suggesting the possibility of utilisation as a functional filler in engineering applications. Subsequent FTIR, SEM and XRD analyses identified that CaCO3 was the main compositions with up to 77.6% of it found to be aragonite. The spectacular high aragonite content compared to well-investigated Crassostrea spp. suggested an opportunity for the utilisation of refined abalone shell as a source of biomedical engineering due to its potent biocompatibility. Additionally, safety evaluations on whole shell also outlined that all investigated samples were safe when utilised as a crude calcium supplement for populations > 11 years old, which could be another viable options of utilisation. This article could underpin abalone and akoya industries actions to fully utilise existing waste streams to achieve a more sustainable future.

A series of triphenylamine-derived fluorophores attached to a Cu-based MOF for gaseous CO optical sensing: synthesis, performance, and mechanism.

A series of triphenylamine-derived fluorescent dyes were attached to a Cu2+-containing MOF (metal-organic framework), denoted as Pm@CuMOF. The molecular structures of these dyes were discussed by the single crystal structures. Their major absorption bands peaked at 410-450 nm, showing emission bands ranging from 556 to 586 nm with emission quantum yields ranging from 8.0 to 15.1%. It was found that the [-N(C2H5)2] group generally improved sensing performance, and the -OH group in the dyes helped the Cu2+ quenching effect. Pm@CuMOF was observed by SEM as nanorods with a width of ~100 nm and a length of 300 nm. Their XRD patterns and N2 adsorption/desorption isotherms were recorded to confirm their porous structure. A low probe loading level of ~4% was determined by TGA result. The CO sensing mechanism was revealed as a Cu2+/Cu+-involved sensing mechanism based on the result of NMR titration, IR, XPS, and EPR. The fluorescence of these triphenylamine-derived dyes was firstly quenched by CuMOF. In contact with CO, Cu2+ was reduced to Cu+, accompanied by the release and fluorescence recovery of the fluorescent dyes, showing emission turn-on effect towards CO gas. Pm@CuMOF showed increased emission intensity at CO level of 0.005% (versus N2), with response times ranging from 123 s to 280 s (depending on various temperatures). Good selectivity was observed over competing alkane gases, with stable emission for at least 5 days, but no linear calibration plots were observed.

Impact of Chemical Properties Crumb Rubber with Different Waste Tire in Hot Mix Asphalt Design

The purpose of this research is to assess the impact of chemical properties of rubber crumbs for various types of waste tires mixed in design asphalt. This paper gives a scientific contribution of the chemical properties in relationship with the mix design asphalt. Many tires are replaced and dumped as waste in many parts of the world every year. This has created severe environmental problems such as pollution which governments of many nations spend a lot of budgets to manage every year. However, incorporating rubber crumbs as part of asphalt construction would help solve the environmental pollution problem in the world. The analysis is important because chemical properties such as Zn, Carbon, and Mg, have different characteristics that must be considered in making the best asphalt mix design. This would help to achieve alternate solutions. Furthermore, Utilizing XRD, FTIR, and TGA, the granules of several kinds of waste tire were examined. To achieve the best mix design for the asphalt, the results had many viewpoints. The TGA result demonstrated that all waste tires decomposed at the temperature of 500°C. However, the truck tire waste had the highest maximum thermal decomposition temperature of 587°C. The FTIR result showed that all the tire waste has similar chemical functional groups of polystyrene. The result of XRF showed that truck tire waste possesses the highest Zn content which is considered as dangerous element to the environment.

Evidence through Thermal Analysis of Retro Diels-Alder Reaction in Model Networks Based on Anthracene Modified Polyester Resins.

The present work is focused on polyester resins obtained from the diglycidyl ether of bisphenol A and anthracene modified 5-maleimidoisophthalic acid. Because the maleimide-anthracene Diels-Alder (DA) adduct is stable at high temperatures, it is considered a good option for high performance polymers. However, the information related to the retroDA reaction for this type of adduct is sometimes incoherent. A detailed thermal study (conventional TGA, HiRes TGA, MTGA, DSC, MDSC) was performed in order to establish whether the rDA reaction can be revealed for this type of anthracene modified polyester resins. The TGA method confirmed the cleavage of the anthracene-maleimide DA adduct, while the DSC demonstrated the presence of anthracene in the system. At high temperatures, unprotected maleimide homopolymerizes and/or reacts with allyl groups according to the -ene reaction. Therefore, the thermal DA reaction is not displayed anymore upon the subsequent cooling, and the glass transition region is registered at a higher temperature range during the second heating. The use of sample-controlled thermal analysis (HiRes TGA) and MTGA improved the TGA result; however, it was not possible to separate the very complex degradation processes that are interconnected.

Study of thermal and mechanical behavior by analyzing reinforcement effect of graphene nanoplatelets on polyamide-66 composite system developed via melt-mixing technique

In the present study, graphene nanoplatelets (GNP) reinforced polyamide 6,6 (PA-66) composite was studied to investigate the thermal and mechanical properties of PA-66/GNP composite. The composites were developed by varying wt% (1, 3, 5, and 10 wt%) of GNP loading using a co-rotating, intermeshing, twin-screw extruder via melt-mixing and injection molding process. In order to understand the thermal and mechanical behavior of PA-66/GNP composite, various thermal (TGA and DSC) and mechanical (tensile, impact, and flexural) tests were carried out. The FTIR spectral analysis was done to identify the presence of different functional groups in the PA-66/GNP composite, indicating the strong enough Vander-Waals interaction between the PA-66 matrix and GNP filler contents. The TGA result shows a significant enhancement in the thermal stability of the composite by increasing wt% of GNP. The DSC analysis exhibits a significant reduction in enthalpy of fusion (∆Hm) and a decrease in the degree of crystallinity with increasing wt% of GNP, reflecting a depressed form of α-crystalline structure. Further, the significant growth in tensile modulus and tensile strength were identified under the mechanical performance of the PA-66/GNP composite. An increasing trend in tensile modulus and tensile strength characteristics was observed, and tensile modulus exhibited an enhancement of ∼96% than pure PA-66 at 10 wt% of GNP. Also, the tensile strength is found to be ∼16% higher than that of pure PA-66 matrix. Similarly, the impact test result shows a decreasing trend in impact strength on increasing wt% of GNP reinforcements, indicating the restriction to the molecular mobility due to improved brittle behavior. Further, the flexural modulus is found to be increased by ∼28% at 10 wt%, and the flexural strength is found to have an enhancement of ∼9% at 3 wt% than pure PA-66 polymer matrix of GNP loadings, respectively. The influence of GNP filler content reinforced PA-66 composite on the thermal and mechanical properties is found to be noteworthy.

Ball mill-hydrothermal method for one-step synthesis of zinc oxide/carbon quantum dot (ZnO-CQD) nanocomposites as photocatalyst for degradation of organic pollutants

In this work, we report a cost-effective, green, one-step, and new method without any extra materials to prepare ZnO/CQD photocatalyst. Hence, ZnO nanoparticles and zinc oxide/carbon quantum dot (Z-CQD) nanocomposites were synthesized using zinc salt, KOH, and sucrose through the new green ball mill-hydrothermal method. The prepared nanomaterials were characterized by FT-IR, TEM, XRD, FE-SEM, TGA, and UV–Vis absorption. The analysis of the TGA result shows the presence of around 6 wt% of CQD in Z-CQD nanocomposite. The presence of CQD in ZnO nanoparticles decreased the bandgap. The photocatalytic performance of ZnO and Z-CQD were compared by evaluating the degradation of phenazopyridine (PhP), a drug pollutant, and rhodamine B (RhB), an organic dye pollutant, under UV light. The results showed that the degradation rate of RhB is higher than that of PhP. In addition, in the case of RhB, the degradation rate by Z-CQD is higher than that of pure ZnO. Therefore, the presence of carbon quantum dots showed a positive effect on the rate of photocatalytic degradation.

Synthesis and characterization of mehtylammonium bismuth iodide via solvent engineering

Hybrid organic–inorganic halide perovskites (OIHPs) are an emerging class of photovoltaic materials that have gained tremendous attention in the field of optoelectronics. This work aims to investigate the characteristics of bismuth-based halide perovskite via solvent engineering for solar cell application. A bismuth-based organo-inorganic perovskite was synthesized and characterized for solar cell application via solvent engineering using Gamma Butyrolactone (GBL) as the based solvent and enhanced with Methylamine (MA) and acetonitrile (ACN). A solution processing facile method was adopted in the synthesis of the perovskite. The solvent engineering aims to tune its band gap and a remarkable band gap of 1.58eV which is within the range of an ideal band gap (1.5-1.6) required for solar cell application. The XRD micrograph exhibited several narrow sharp peaks which indicated crystallinity formation of the synthesized sample with 86% crystallinity. The FESEM/EDS micrograph indicated nature of the formed crystals and the chemical composition of the sample. A multilayer heptagonal crystal was observed. The TGA result showed that the sample is thermally stable at a temperature of 200oC before degradation occurred.

Assessment of mechanical properties of fiber reinforced cementitious system exposed to high temperature

AbstractIn this study, it was aimed to determine the optimum fiber type and usage ratio by examining the effect of fiber type and usage rate on the properties of mortar mixtures exposed to high temperatures such as 300°C, 450°C, and 600°C. For this purpose, mixtures were prepared by substituting polypropylene (PP), polyamide (PA) and basalt (B) fibers in proportions as 0.25%, 0.50%, 0.75%, and 1% instead of aggregate. Unit weight, compressive‐flexural strength, ultrasonic pulse velocity (UPV), and permeability properties of mixtures were determined. Regardless of fiber type, flexural strength and permeability increased, UPV decreased with the addition of fiber. Basalt fiber mixtures exhibited the highest performance in terms of flexural strength. PP fiber mixtures exhibited the best performance in terms of permeability, ultrasonic pulse velocity and dynamic modulus of elasticity. SEM analyzes showed that PP fibers exposed to 600°C melted, leading to the formation of channel voids. According to TGA result, approximately 15% mass loss was observed in the control sample at 600°C.

3D printing of high solid loading zirconia feedstock via screw-based material extrusion

Zirconia ceramic (3Y-TZP) feedstocks with solid loadings from 50 vol% to 68 vol%, in a 60:40 paraffin wax to LDPE ratio binder system, were prepared and printed using a screw-based material extrusion printer. A two-step debinding process involving solvent debinding (cyclohexane + ethanol) and thermal debinding (140 °C–600 °C at 0.2 °C/min) followed by sintering at 1500 °C for 2 h was employed. Tests performed include TGA, density test, Vickers hardness and fracture toughness, XRD, and SEM. The TGA result showed two significant drops in weight starting at 180 °C and 380 °C, which corresponds to the decomposition of paraffin wax and LDPE, respectively. A minimum of 40 wt% of soluble binder was removed from the green sample after solvent immersion for 3 h at 40 °C for solid loadings ≥55 vol%. High solid loading feedstocks produced samples with comparable density, Vickers hardness and fracture toughness, which are 97.5%, ∼12.3 GPa, and ∼5.5 MPa m1/2, respectively; while XRD and SEM shows no adverse tetragonal to monoclinic phase transformation and grain growth, respectively. This study demonstrates that 3D printing of granular 3Y-TZP ceramic feedstock via screw-based material extrusion technique is feasible even with high solid loadings, which is usually difficult to fabricate into flexible filaments and print due to high viscosity.

Senegalia Catechu activated carbon incorporated Ba-alginate composite beads for the removal of Safranine B: modeling studies

The present investigation depicts the removal of Safranine-Bdye from aqueous solution using senegalia Catechu activated carbon incorporated Ba-alginate composite beads. The alginate beads were synthesized by metal encapsulation technique using BaSO4 as an encapsulating agent. The Safranine-B dye removal efficiency was determinedby the modeling equations like Langmuir and Freundlich. The nature of physical, chemical force of attractionbetween the adsorbate vs. adsorbent and feasibility was determined using pseudo order equations of first andsecond. The progressiveness of the interaction process was predicted by intraparticle diffusion, enthalpy, entropy and Gibbs free energy model equations. Experimentally obtainedoutcomes were implied that the adsorption of Safranine-Bwas feasible for all the parameters used in this study. Furthermore, the predicted diffusion valueswere revealedthat the contact between Safranine-B versus composite beads was well diffused. The surface morphology of virgin and Safranine-B loaded images confirms that the Safranine-B was strappinglybind on outerlayer of the composite. The results of the FTIR spectrum indicatethe Safranine-Bwas intensively attached on thecomposite surface. The TGA result revealsthat the Ba composite bead has predominant temperature bearing nature.

Removal of toxic dye from dye-laden wastewater using a new nanocomposite material: Isotherm, kinetics and adsorption mechanism

In this study, (hemi)cellulosic biochar-based environment-friendly non-toxic nanocomposite (nAg-AC) was fabricated for an inordinate overlook of toxic dye-laden wastewater depollution. This hybrid nanocomposite grafted with silver nanoparticles, numerous hydroxyl and π-bond containing functional groups exhibited outstanding physicochemical properties. FESEM images indicated the heterogeneous porous structure of nAg-AC, while BET analysis revealed mesoporous property with a significant increment of overall surface area (132%). Imbedding of silver nanoparticles and the presence of multiple hydroxyl groups was evident from the XRD and XPS spectrum. Further, the TGA result indicated excellent thermal stability, and FTIR analysis suggested the involvement of surface functional groups like –OH, =C = O, =NH, =C = C = , and –CH in Rhodamine B (RhB) adsorption. The adsorbent matrix provided the overall mechanical strength and facilitated recycling, while the functional matrix (biochar) provided the adsorptive locus for augmented RhB adsorption efficiency (92.77%). Experiments pertaining to adsorption isotherms and kinetics modeling suggested that RhB was removed through multilayer chemisorption on the heterogeneous nAg-AC surface. The main RhB adsorption mechanism included cumulative efforts of H-bindings, π-π stacking interaction, pore-filling, and electrostatic interactions. The nAg-AC maintained mechanical robustness with significant RhB adsorption even after three consecutive regeneration cycles signifying facile recycling. The nAg-AC displayed an outstanding efficacy for the real industrial wastewater depollution, indicating high effectiveness for practical environmental applications. Finally, the cost analysis (incorporating economic, environmental, and social dimensions) suggested a significant role of the nAg-AC in promoting and establishing sustainable development with the circular economy.

Construction of Mg(OH)2/graphene oxide nanostructures with advanced adsorbing and flame-retardancy performance

The Mg(OH)2/graphene oxide (MHG) nanocomposite was constructed through a facile precipitation method under room temperature. The products were characterized systematically. Results revealed that lamellar Mg(OH)2 nanoparticles have anchored on graphene oxide (GO) successfully. The as-synthesized MHG possessed high specific area of 420.1 m2/g and mesoporous structure, which make it an excellent adsorbent for methylene blue (MB). Freundlich model and pseudo-second-order kinetics model could be used to described the adsorption isotherm and adsorption kinetics perfectly. The thermodynamics parameters revealed the adsorption process was endothermic and spontaneous. Moreover, the resultant MHG nanocomposite was further incorporated into poly (vinyl alcohol) (PVA) to investigate its flame-retardancy for the first time. The limiting oxygen index (LOI) test, UL-94 test and microscale combustion calorimetry (MCC) results indicated that MHG was effective flame retardant for PVA. The TGA result suggested the MHG could improve the stability of PVP effectively. The as-synthesized MHG holds promise to be used as adsorbent in removing contaminants from waste water and flame-retardant for polymers.

Synthesis and Characterization of Imidazole Based Cationic Surfactants as Disinfectants

Citric acid-based cationic surfactants using 1-methyl imidazolium as coordinizing agent has been synthesized and characterized. The cationic surfactants is produced in excellent yields (70%) and has been examined by TGA, FTIR, 1H NMR and are found to have good surface-active properties. FTIR analysis showed the presence of ester confirmed by 1H NMR (the chemical shift value of 3.7 ppm and 3.8 ppm is due to the presence of an ester) in the surfactant. The biodegradability confirmed by BOD analysis. It is found that cationic imidazolium surfactants having surface tenstion of (12 mN/m) with chloride as a counter ion. The results show that cationic imidazolium surfactants with longer hydrophobic chains have a lower CMC value. TGA result shows good thermal properties of cationic surfactant. Invitro study of cationic surfactant over fungal cell indicates its antifungal activity (70% inhibition at 350 ppm) and its appliaction as disinfactant.

Thermal Performance Enhancement of CuO-Paraffin Nano-Enhanced Phase Change Material

The current work is focused on the synthesis and characterisation of CuO (copper oxide) nanoparticles and investigating the thermal conductivity of CuO nanofluids. CuO was prepared using a wet chemical approach. Newly prepared nanofluid passes through tests to explore its industrial and other applications. An X-Ray diffraction pattern was used to find the average crystalline size of CuO nanofluids. The scanning electron microscope and transmission electron microscope were used to find the morphology, particle shape and size. Dynamic Light Scattering (DLS) was used to find the agglomerated size of nanofluids. The optical properties of the CuO nanofluids were evaluated using ultraviolet-visible absorption spectra. The KD2 pro thermal property analyser was used to find the thermal conductivity of CuO nanofluids and it was discovered that as particle loading rises, thermal conductivity also increases. The performance enhancement of Nanoparticle-Enhanced Phase Change Material (NEPCM) samples was analysed using FTIR, TGA and DSC techniques. FTIR result shows that the physical contact of copper oxide and paraffin does not influence the chemical structure and stability of the NEPCM samples. TGA result shows that as the CuO percentage increases, it enhances the physical bonding interaction between PW and the nanoparticle and improves the stability of NEPCM samples. DSC analysis shows that CuO reduced the impact of super-cooling during the melting and solidification stages. The nano CuO was used to speed up crystallisation and decrease the super cooling effect of paraffin wax. Further, CuO successfully stabilised the heated surface's temperature fluctuation during melting and solidification.

Physico-mechanical Properties of Basalt-based Brake Pad as Alternative to Ceramics Brake pad

A basalt-based automobile brake pad was developed through optimization of the volume fractions and manufacturing parameters, a mathematical model was developed based on rule of mixture for the optimization of the volume fraction and the solution obtained using excel solver is as follow; basalt 38%, cast iron chips 26%, bronze 12%, glass fibre 12% and phenolic resin 12%. The manufacturing parameters were design using full factorial design of three levels and three factors, twenty-seven runs were obtained from the design, consequently twenty-seven samples were produced by compression moulding. The constituent materials were properly mixed to obtained homogeneous mixture and compressed into a mould with a cavity similar to the shape of the friction pad this was done at different moulding pressures of 30MPa, 27MPa and 24MPa, the curing temperatures were 1800C, 2000C and 2200C and the curing of 5minutes, 10minutes and 15 minutes as obtained from the factorial design. The samples produced were subjected to tests, the results showed that the basalt brake pad has the following properties; compressive strength of 137mPa, coefficient of friction 0.476, hardness 70HRB, density of 2768kg/m3 thermal conductivity of 0.66W/mK, water absorption of 0.377%, oil absorption of 0.25%, void content of 18.93%, wear rate of 9.0X10 -4g/m and the TGA result shows that the basalt-based brake pad is thermally stable up to a temperature of 5000C. The properties of the basalt-based brake pad are within the acceptable range and can satisfactorily substitute basalt.

Extraction of cellulose from oil palm empty fruit bunch using eco-friendly solvents for preparation of transparent cellulose thin film

The purpose of this research is to extract the cellulose using eco-friendly reagents of hydrogen peroxide and formic acid and determine the optimum reaction time for delignification process. The extracted cellulose and characterised using FTIR, TGA and PSA. The percentage yield of extracted cellulose were calculated. The highest yield was found to be 65.78 % at reaction time 120 min. The FTIR spectral studies confirm the removal of lignin from the delignified cellulose at peak 1613 cm−1 and the TGA result shows the thermal degradation of extracted cellulose at 329.04, 329.92 and 330.99 °C at reaction time 60, 90 and 120 min. The PSA studies provided the evidence of extracted particle size of the cellulose become finer as the reaction time increase. The particle size observed for delignified cellulose at 60, 90 and 120 min are 68.4, 64.6 and 57.3 μm. The extraction of cellulose and characterization to determine the optimum reaction time was able to obtain. From the result obtained, it can be concluded that the longer the reaction time, the higher the percentage yield of cellulose extracted. Film formation was later carried out using the extracted cellulose from different reaction time.

Phase change microcapsules with high encapsulation efficiency using Janus silica particles as stabilizers and their application in cement

This study reports the preparation of phase change microcapsules (PCMs) which possess high encapsulation efficiency, this is achieved by using Janus silica particles (JSPs) as stabilizers in combination with Pickering emulsion and suspension polymerization methods. The inner shell and outer shell of the PCMs are polyacrylate and JSPs respectively. The morphologies and particle sizes of the PCMs can be controlled well, as evidenced by SEM and optical microscopy characterization. The amount of JSPs and functional monomer methacrylic acid play key roles in controlling the morphologies of the PCMs. The encapsulation ratio of PCMs can be adjusted with the encapsulation efficiency reaching as high as 99.6%. The phase change enthalpy of the PCMs is 175.1 J/g when the core/inner shell/outer shell weight ratio of n-octadecane/polyacrylate/silica microcapsules is 70:21:1. The TGA result indicates that the PCM is stable up to 150 °C. The enthalpy of PCM remains almost unchanged after 7560 phase change cycles, illustrating the PCM exhibits excellent thermal reliability and durability. The PCM-modified cement plate shows a remarkable cooling effect, which means that this type of PCM has promising applications in the construction field.

Preparation of novel flexible freestanding conducting polyaniline nanocomposite films using recent generation polycarboxylate ether

Novel flexible freestanding films of polyaniline–polycarboxylate ether nanocomposites (PAni–PCE NCs) were first synthesized effectively by a one-step in-situ polymerization of aniline in the presence of recent generation superplasticizer PCE as a polyanionic dopant cum film-forming agent. Various spectrochemical methods were used to characterize the molecular structures of the produced PAni–PCE NCs. In this work, PAni–PCE NCs show the lattice fringes structures by HR–TEM study for the first time. The electrical conductivity of flexible freestanding PAni–PCE nanocomposite films was measured using a four-probe method. The maximum conductivity was found in the range of 1.5 S cm−1 for PAni–PCE5 nanocomposite film. FT–IR results confirmed that PAni had been successfully doped or incorporated into the PCE matrix. The XRD pattern validated the crystalline nature of novel flexible freestanding PAni–PCE nanocomposite films. By increasing the concentration of PCE from 0.033 M to 0.165 M, the morphological transition from nanorods to nanosheets and nanoneedles was observed in the SEM image of the flexible freestanding PAni–PCE NCs film. From the TGA result, flexible freestanding PAni–PCE nanocomposite films showed higher thermal stability than pure PAni.

Antimicrobial and antioxidant activity of impregnated pectin and alginate based bio composite packaging material for fresh produce safety

The objective of the presented work was to develop, characterize and evaluate the biodegradable, proactive, protective, novel active packaging blend films of low methoxy pectin and sodium alginate and identify their antimicrobial and antioxidant ability with plant-based natural phytochemicals like cinnamaldehyde. Different blend films were prepared in different ratio like (75% pectin ± 25% sodium alginate) (100% pure pectin), (100% pure sodium alginate), (100% Pectin+200µL cinnamaldehyde), 75% pectin+25 sodium alginate+700µL cinnamaldehyde), The antimicrobial activity was tested against foodborne pathogens E. coliO157:H7 (MTCC 90), and Salmonella Typhi (MTCC 733) and zone of inhibition were recorded. On the basis of linear correlation analysis (R2), the free radical scavenging activity of 10% bio-composite incorporated with 0.30% cinnamaldehyde blends was 0.9235 for DPPH scavengers where citric acid were used as a positive control. The film was characterized by TGA, DSC, FTIR, and XRD analysis result was shown a significant effect on thermal behavior.

Catalytic renovation of non‐edible oil to biodiesel production through sulfated Mg‐Al 2 O 3 (10) catalysts

Magnesium-alumina (Mg-Al2O3) composite was synthesized by sol-gel method. The SO42− catalyst supported Mg-Al2O3 was prepared by three different methods such as solution, hydrothermal, and vapor phase. The as-synthesized materials were characterized by different physicochemical techniques. The acid sites of Mg-Al2O3 (10) composite were enhanced by depolymerization of triglyceride (jojoba oil) to produce free FFA. Catalyst prepared by hydrothermal methods exhibits high acid sites of 3.44 mmol g−1 of NH3. Sulfidation of catalysts play a vital role in the catalytic conversion of jojoba oil by methanol activation. SO42−/Mg-Al2O3 (10) catalyst reveals 99% conversion efficiency tested under optimized conditions of jojoba oil to methyl ester (biodiesel). TGA result confirmed the S2/Mg-Al2O3 (10) catalyst is stable upto 800°C and weight loss of 19.2%. The recyclability of the S2/Mg-Al2O3 (10) catalyst reveals reasonably acceptable conversion efficiency after sixth cycle and this catalyst is found to be suitable for the industrial biodiesel production.