Shell Waste Research Articles

Sustainable colour, sulfate and phosphate removal from vegetable oil refinery wastewater using snail shell waste extracted-chitin-chitosan: Equilibrium studies and toxicity assessment of used adsorbents

Direct discharged of vegetable oil refinery wastewater without treatment can cause severe environmental pollution, corrosion and clogging of pipes. This work is aimed at investigating the use of snail shell extracted chitin and chitosan fortified with alum in removing colour, sulfate and phosphate from vegetable oil refinery waste water, monitoring the pH, and testing the toxicity of the used materials on the growth performance of maize. Chitin and chitosan with good adsorbent properties were produced from snail shells. The spent chitin/alum and chitosan/alum were recycled and their toxicities on the growth performance of maize tested. The studied wastewater had pH of 10.40, sulfate and phosphate concentrations of 3100 and 1561.3 mg/L respectively. Maximum removal capacities for sulfate and phosphate of 842.54 and 728.07 mg/g were respectively obtained for chitin, and respectively 934.97 and 728.00 mg/L for chitosan against colour removal of 0.96 and 0.95 Absorbance/g respectively on chitin and chitosan. Nearly 100% of colour and phosphate were removed by chitin and chitosan systems for all tested parameters against a maximum of 84% for sulfate by chitosan at pH 10 and 80% for chitin at pH 4. From Pseudo-second order kinetics, phosphate and sulfate removal were faster on chitin than chitosan while colour removal was faster on chitosan than chitin. Recycled adsorbents enhanced maize germination and survival than the control where they were absent. Tested adsorbents are effective in improving quality of studied effluent, requiring no electricity and can be used as fertilizers, ensuring clean environment and generation of more revenue

Evaluating the Liming Potential of Mytilus galloprovincialis Shell Waste on Acidic Soils

The sustainable management of aquaculture by-products is crucial for advancing circular economy practices. Mediterranean mussel shell waste, rich in calcium carbonate, presents a sustainable alternative to conventional liming materials, especially for mitigating soil acidification, a very important and common issue that limits crop productivity. This study evaluated the effectiveness of processed mussel shell waste in enhancing soil pH, organic matter, and nutrient availability. A 180-day pot experiment using highly acidic soil (pH < 4.5) collected from a local field was conducted in a Completely Randomized Design. Treatments involved two grain sizes of mussel shell powder (Fine: <1 mm; Coarse: 1–2 mm) at rates between 0.1 and 6%. Treated soil pH was measured monthly, whereas organic matter, available phosphorus (P), and exchangeable potassium (K) were measured at the beginning and the end of the experiment. The results revealed significant improvements in pH, organic matter, available phosphorus (P), and exchangeable potassium (K), particularly in the Fine Powder treatments. However, total nitrogen (N) remained unaffected. These findings highlight the potential of mussel shells as an eco-friendly and cost-effective amendment, advancing sustainable agriculture and waste recycling, thus contributing to broader conservation efforts by reducing the environmental footprint of aquaculture waste and supporting biodiversity and ecosystem resilience through sustainable resource management.

Development and characterization of sustainable concrete with marine shell waste

Resumo As atividades de mariscagem e malacocultura produzem uma grande quantidade de resíduos sólidos compostos por conchas marinhas. O impacto ambiental do descarte inadequado pode ser atenuado com estratégias de reaproveitamento. O objetivo deste trabalho é investigar a viabilidade do uso de resíduo de conchas marinhas com substituintes parciais de agregados no concreto. As características físicas do agregado reciclado foram investigadas através das técnicas de Microscopia de Força Atômica (MFA) e Microscopia Eletrônica de Varredura (MEV) a fim de esclarecer aspectos da superfície de contato com a pasta; as características químicas e mineralógicas foram investigadas por meio dos ensaios de fluorescência de raios-X e difração de raios-X; e o ensaio de resistência à compressão foi conduzido em amostras de concreto foram moldadas para avaliação do comportamento destes materiais do comportamento destes materiais como agregado (concha tipo A) e fíler (concha tipo B). Concluiu-se que o uso de até 20% de substituição de concha marinha como agregado graúdo e 10% como filer mostrou viabilidade para aplicações em concretos estruturais e, de forma complementar, teores de até 30% podem ser direcionados à concretos não estruturais.

Hydroxyapatite (HAp) Extracted from Cockle Shells with Polylactic Acid (PLA) for Bone Implant Application

Cockle shell waste has been utilized to produce HAp powders for biomedical applications. This research involves creating HAp powder through a precipitation method and analyzing the properties of CaCO₃, CaO, and HAp. A composite PLA/HAp material was produced with varying ratios of 10%, 20%, and 30% HAp for tensile test samples. The results show that HAp derived from cockle shells contains calcium and phosphorus, similar to commercial HAp. Samples with different weight percentage of HAp provides Young's modulus values comparable to cortical bone (7-30 GPa), with the sample containing 30% HAp achieving the highest value (8.17 GPa), where High Young's modulus values indicate increased stiffness. In summary, cockle shell-derived HAp is a promising material for biomedical applications.

Bio-colonisation, durability, and microstructural analysis of concrete incorporating magnetite and oyster shell waste aggregates in marine environment

This study evaluates the impact of bio-colonisation and seawater attack on the durability, microstructure and mineralogy of two distinct concrete formulations. These formulations are designed to meet the specifications of marine infrastructure applications, particularly those intended as biomimetic solutions for infrastructures typically used for boat anchoring, which are commonly responsible for the displacement and destruction of marine habitats. The first formulation incorporates magnetite aggregates, resulting in a heavy concrete capable of stabilising the base structure of the biomimetic concrete mooring. In the second formulation, natural gravel is partially substituted by oyster shell waste, to reduce the carbon footprint of these marine infrastructures. Experimental tests were conducted to evaluate the bio-colonisation and durability of the two concrete formulations under marine exposure. After 24 months of immersion, the surface biomass on both formulations exhibited similar kinetic bio-receptivity, primarily attributed to the binder and surface roughness rather than the type of aggregates used. The porosity accessible to water decreases in marine conditions, suggesting that the biofilm contributes to this decrease. Durability results indicate that while both concrete types deteriorate under seawater exposure, the oyster shell aggregates demonstrated better resilience to natural seawater aggressiveness compared to magnetite aggregates over long-term exposure. Elemental mapping showed no obvious zonation of elements. However, a slight increase in surface roughness was observed, with no macroscopic damage detected. This research enhances our understanding of how magnetite and oyster shell waste aggregates respond to bio-colonisation and seawater attack, which are critical factors in the development of biomimetic marine infrastructure.

The Quality Study of Hydroxyapatite (HAp)-TiO2 Composites from Pokea (Batissa violacea var. celebensis) Shell Waste by Hydrothermal, Microwave and Precipitation Methods

Research on the quality study of hydroxyapatite (HAp)-TiO2 composites from Pokea (batissa violacea var. celebensis) clamshell waste by hydrothermal, microwave and precipitation methods have been successfully conducted. This study aims to determine the characteristics and quality of HAp-TiO composites2 synthesized from Pokea clam shell using three different methods, namely hydrothermal, microwave and precipitation. FTIR characterization showed the absorption of PO4-3 functional groups in the wave number range 567-1091 cm-1, -OH and -NH groups at wave numbers 3444-3448 cm-1, and Ti-O groups at 567-632 cm-1. XRD analysis revealed a diffraction pattern at 2θ = 26.67o, with crystal sizes of HAp-TiO2 material of 80.20 nm, 71.47 nm, and 73.28 nm for hydrothermal, microwave and precipitation methods, respectively. The mechanical properties showed that the highest compressive strength of the HAp-TiO2 composite was obtained in the hydrothermal method (6.07 MPa), followed by the precipitation method (5.19 MPa) and microwave (5.08 MPa). The material density test results for the hydrothermal, microwave and precipitation methods were recorded at 2.27 MPa, 2.12 MPa, and 1.73 MPa. The test results showed the highest value in the hydrothermal method of 24.24 MPa, while the microwave and precipitation methods produced hardness of 18.61 and 18.83 MPa, respectively. Digital optical microscope analysis showed the surface morphology of the material to be uniform, refined grains with pores. The results in this study indicate that the hydrothermal method produces composites with better mechanical quality and crystal structure than other methods.

A green route of antibacterial films production from shrimp (Penaeus monodon) shell waste biomass derived chitosan: Physicochemical, thermomechanical, morphological and antimicrobial activity analysis

As a result of the excessive dependency on synthetic polymer/plastic products, both industries and mankind have been generating a huge amount of hazardous plastic waste. That could be recognized as a breakneck tread on for total environment due to their nonbiodegradable nature. Thus, to solve this problem replacement of the hazardous synthetic fossil-based plastic with biopolymeric materials is very crucial. But, due to the deficiency of the most critical understanding, designing of the biopolymeric materials from natural resources have signified a big challenge. However, researchers are trying to develop a suitable route to solve this issue. By this study a green route of production of antibacterial films from the agro-waste biomass has been developed. Whereas the highly active chitosan were extracted from shrimp (Penaeus monodon) shells by conducting demineralization, de-proteinization, and deacetylation reaction. The chitosan-acetate films were fabricated by using the EIPS operation to enhance their overall properties. The samples were characterized by SEM, ATR-FTIR, 13C CPMAS NMR, TGA, TS, biodegradability, and antimicrobial activity exploration. The results advised that the newly fabricated biofilms are highly thermally stable, possessed several active binding sites with a uniform nonporous solid microstructure. Also exhibited a higher mechanical tensile strength (nearly 120.27 ± 0.091 N/mm2), elongation properties (around 43.98 ± 0.098 %), and a high antimicrobial activity. While the maximum zone of inhibition and MIC value were found around 45 mm and 5 µg for Staphylococcus aureus. Due to these outstanding properties, this biofilm would be beneficially used in several engineering, industrial, and bio-medical sectors for the green environmental protection.

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.

Thermal Oxidation Degradation Characteristics and Kinetic Analysis of Waste Shell Powders for Efficient Utilization and Environmental Protection

ABSTRACT The thermal oxidation degradation and kinetic behavior of four waste shell powders: Hyriopsis cumingii, abalone, scallop, and clam were investigated. The thermal oxidation degradation process was elucidated using thermogravimetric analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and the Coats-Redfern method. This process typically occurs in four stages, with the decomposition of CaCO₃ (Stage III) being pivotal. Notably, clam and scallop powders exhibited the highest CaO yields of approximately 55.1% and 55.0%, respectively. Although abalone powder had a lower yield of 50.2%, it demonstrated the lowest activation energy of 118.08 kJ/mol in Stage III, suggesting potential energy and cost savings during CaO conversion. High-temperature calcination altered the chemical composition and microstructure of the shell powders, resulting in rough and porous CaO surfaces conducive to heavy metal ion and pollutant adsorption. The research provides a theoretical framework and experimental validation for the sustainable utilization of calcined shell powders, fostering efficient shell resource management and environmental protection.

High-Performance Concrete from Rubber and Shell Waste Materials: Experimental and Computational Analysis.

Waste and its environmental impact have driven the search for sustainable solutions across various industries, including construction. This study explores the incorporation of solid waste in the production of eco-friendly structural concrete, aiming to reduce pollution and promote ecological and sustainable construction practices. In this context, two types of eco-friendly concrete were produced using marine shells and recycled rubber as waste materials and compared with conventional concrete through experimental and computational approaches. The results demonstrated that the concrete with marine shells achieved a compressive strength of 32.4 MPa, 26.5% higher than conventional concrete, and a 1% reduction in weight. In contrast, the recycled rubber concrete exhibited a compressive strength of 22.5 MPa, with a 2 MPa decrease compared to conventional concrete, but a 4.3% reduction in density. Computational analysis revealed that porosity affects Young's modulus, directly resulting in a reduction in the maximum achievable strength. This work demonstrates that it is feasible to produce eco-friendly structural concrete through the proper integration of industrial waste, contributing to decarbonization and waste valorization.

Characterization of Hydroxyapatite Derived from Scallop Shell Waste Synthesized by Sonochemical Method with Different Temperature Calcination

One common bio-ceramic material used in the biomedical industry is hydroxyapatite. Because of its crystallographic and molecular resemblance to the hard tissues of the human body, hydroxyapatite is thought to form. Scallop shells are one natural source of hydroxyapatite, which is high in calcium. This study examines how the calcination temperature affects the characteristics of hydroxyapatite made from leftover scallop shell. Hydroxyapatite was synthesized via the sonochemical method, with calcination conducted at temperatures of 900°C, 1000°C, and 1100°C. The hydroxyapatite that was prepared was assessed using X-ray diffraction (XRD) to determine the phase and crystallite size, Scanning Electron Microscopy (SEM) to conduct a morphological investigation, and Fourier Transform Infrared (FTIR) spectroscopy to conduct a functional group analysis. Phases resulting from varying calcination temperatures include hydroxyapatite and β-tricalcium phosphate. The crystallite size of hydroxyapatite enhanced with rising temperature. The morphology of hydroxyapatite exhibited agglomeration in all samples, with grain size escalating alongside the increase in calcination temperature. The functional groups generated under the three temperature fluctuations include O-H, P-O, PO43-, and O–P–O groups. The calcination temperature significantly influences the characteristics of produced hydroxyapatite and impacts its biocompatibility as a bone implant material.

Captivating Combustion Traits of Bio-Oil Droplets Enriched with Bio-Additives from the Areca Shell Waste

Fuel derived from crude vegetable oil, such as coconut oil, holds promise as an alternative energy source to mitigate the increasing reliance on fossil fuels driven by population growth and industrial activities. The experiment involved suspending a single droplet of crude coconut oil mixed with activated carbon from areca shell waste and placed at the junction on R-type thermocouple (Pt/Pt-Rh13%). The droplets were ignited using a hot wire and subjected to atmospheric pressure and room temperature. Coconut oil comprises a saturated triglyceride carbon chain compound of approximately 91%, and areca shell waste possesses a porous structure that fosters favorable interactions between fuel molecules. The droplet combustion method was selected to streamline the process and enhance the contact area between air and fuel, thereby boosting the reactivity of fuel molecules. The research found that adding activated carbon shortens the carbon chain, making it more reactive and easier for the fuel to ignite. Specifically, activated carbon significantly enhances fuel performance at a concentration of two parts per million (ppm). At this level, the fuel absorbs heat more effectively and ignites faster compared to one ppm and three ppm levels. Moreover, the results show that heat absorption occurs slowly at one ppm, while at three ppm, the increased molecular mass of the fuel can strengthen carbon-bonding forces. These factors contribute to a longer ignition time for the fuel. The findings suggest that the activated carbon from areca shell waste can play a good role as a combustion catalyst, where overall, fuel performance increases.

Effect of watering interval on growth and production of 2 maize (Zea mays L.) varieties in drought stressed media treated with chitosan

Abstract Maize is an important food source after rice, but its production is often hampered by drought stress. This study aimed to assess the effect of watering intervals on two maize varieties by applying chitosan from black soldier fly (Hermetia illucens) cocoon shell waste. The study used a Randomized Block Design (RBD) with two treatment factors. The first factor was watering interval consisting of five levels: daily watering, no watering for 4, 8, 12, and 16 days. The second factor was maize variety, Bonanza F1 and Bisi-18. The results showed that the watering interval had a significant effect on plant height, number of leaves, stem diameter at 7 weeks of age, cob weight, 100 seed weight, root volume and length, and time of female flower emergence. The treatment of Bonanza F1 and Bisi-18 varieties also had a significant effect on plant height at 7 weeks of planting, stem diameter at 6-7 weeks of planting, root volume, root length, female flowering time, cob weight and length. In addition, the interaction between watering interval and maize varieties significantly affected plant height, 100 seed weight, cob length, root volume, root length, and time to female flower emergence.

Circular Economy Perspective of Hifdz Al-Bi'ah Through the Utilization of Shell Waste as Raw Material for Decorative Products

Shell waste, which is often considered a waste material, has great potential to be processed into handicraft products with economic value. Through an environmentally friendly processing process, the waste can be converged into goods that are not only in demand in the market, but also encourage public awareness of the importance of recycling and environmental maintenance. This research aims to explore how often overlooked waste can be processed into decorative items that not only reduce negative impacts on the environment, but also create new economic opportunities for the community. The research method used is qualitative with a descriptive approach, involving observation and interviews with handicraft business actors. The results of the study show that the use of shell waste can increase public awareness of the importance of waste management and environmental protection. In addition, this research highlights the importance of training and innovation in creating attractive and value-added products. Thus, this research makes a significant contribution to the development of a sustainable and environmentally friendly craft industry, as well as encouraging the adoption of circular economy principles in various sectors. In conclusion, the use of shell waste not only meets economic needs, but also contributes to environmental sustainability and improving people's quality of life.

Synthesis of nanochitosan from oyster pearl shell (Pinctada maxima) as renewable energy candidate

The increase in energy needs must be balanced by environmentally friendly technological innovations. Chitosan polymer is one of the technological innovations of energy materials that are being developed by many developed countries. This research aimed to identify the potential of oyster pearl shell waste as a source of electrolyte polymers. The study was conducted experimentally by synthesizing chitosan nanoparticles from chitosan using the ionic gelation method. Chitosan is obtained through the isolation method from Pinctada maxima oyster pearl shell waste. The isolation method is carried out by three processes: deproteination, demineralization, and deacetylation. Several characterizations were carried out to analyze the material from the synthesis, including a proximate test, FTIR analysis, and PSA analysis. Isolated chitosan was identified to have a deacetylation degree that reached 88.63% with the formation of OH and NH2 functional groups. In general, the proximate tets data has shown that the obtained chitosan already meets the Indonesian standard SNI 7949:2013. PSA analysis resulted in differences in size distribution, PDI, and zeta potential between chitosan and chitosan nanoparticles. The results were obtained by the average distribution of chitosan particle size of 52.043 μm and chitosan nanoparticle size of 2.3365 μm—the analysis of the potential zeta of chitosan -3.9 mV and chitosan nanoparticle -21,6 mV. Thus, changes in the size of the chitosan material affect its potential PDI and zeta values. The change of these two values is a good indicator of the initial data and the potential of the material as an energy material. Therefore, chitosan polymer is an electrolyte material that can be used as a candidate for environmentally friendly renewable energy materials

Antibody titer after anti-idiotype rabies vaccination with nano-chitosan adjuvant

Background.The rabies virus neutralizing antibodies titers is a public health problem in the world, including Indonesia. Rabies is zoonotic and causes death in humans with a case fatality rate of 100%. Anti-idiotype antibody (Ab2) from chicken immunoglobulin (IgY) can be a substitute antigen for the rabies virus. This research aims to study the potential of rabies vaccine based on anti-idiotype antibody (Ab2) with nano-chitosan as an adjuvant.Materials and methods.The production of Ab2 is derived from purified and characterized chicken immunoglobulins. Nano-chitosan is made from chitosan from shrimp shell waste. Vaccination tests were carried out on rats compared with commercial vaccines as a positive control and physiological solutions as a negative control. The characterization results of IgY Ab2 were IgY rabies with BM ~180 kDa, heavy chains (BM ~60 kDa), and light chains (BM ~30 kDa) of IgY. Nano-chitosan is less than 100 nm in size, can dissolve well, and does not cause side effects in experimental animals.Results.The vaccine formula uses a concentration of 0.5%, where the ratio of nano-chitosan and Ab2 is 1:1. The Ab2 concentration used was about 1000 units per mL of the Ab2 suspension.Conclusion.This study concludes that anti-idiotype antibodies dissolved in nano-chitosan adjuvant can induce the formation of antibodies with titers that are not statistically different from the antibody titers induced by commercial rabies vaccines. Nano-chitosan has a potential vaccine adjuvant candidate, safe to use, and can enhance the immunogenicity of an antigen applied subcutaneously. According to the results of this study, it is recommended that post-vaccination antibody titers be measured regularly: for example, every one week for six weeks after vaccination. This measurement determines the time of the peak of the antibody titer so that the time for revaccination can be determined.

A facile approach towards large-scale synthesis of TiO2 nanoparticles derived from egg shell waste with enhanced UV shielding, nano priming and fingerprint real time object detection through YOLOv8x

This study demonstrates an eco-friendly method for synthesizing TiO2 nanoparticles (NPs) utilizing an aqueous extract derived from egg shell (ES) waste. This study examines the use of TiO2 NPs for detecting Level I-III fingerprint (FP) features via the powder dusting method. The NPs enhance the visualization of ridge patterns, minutiae points, and pore structures in latent prints. Results show improved clarity, making this method promising for high-resolution forensic FP analysis. This paper explores the use of YOLOv8x, a cutting-edge object detection model, for FP analysis. YOLOv8x advanced architecture allows for rapid and accurate identification of minutiae points, ridge patterns, and other essential FP features. Its high precision and real-time detection enhance the efficiency of FP recognition, making it applicable to forensic investigations and biometric authentication. Experimental results show that YOLOv8x outperforms traditional methods in both accuracy and processing speed, highlighting its superiority in FP analysis tasks. The PVA@TiO2 films are engineered to offer excellent transparency, exceptional flexibility, and efficient UV radiation blocking properties, which have been rigorously evaluated across the UV-A, UV-B, and UV-C spectra. Blocking experiments revealed that the PVA@TiO2 (16 wt%) film effectively blocked 90.11 % of UV-A radiation, 92.82 % of UV-B radiation and 92.72 % of UV-C radiation. A solution of TiO2 NPs at environmentally relevant concentrations (20–160 mg/mL) is utilized as a nano-priming agent to improve the germination and early seedling growth of horse gram seeds. Notably, root length increased by 61 %, while shoot length grew by 58 %. The vigor index, an essential indicator of seedling health and strength, is significantly greater in the treated seeds, achieving a value of 2460, compared to 945 in the control group. This study presents a multifunctional material designed for its efficacy in FP detection, UV blocking capabilities, and beneficial effects on seed germination, providing a wide range of potential applications.

Synthesis and performance characterization of green desiccant from cockle shell and marble waste

Synthesis and performance characterization of green desiccant from cockle shell and marble waste

Synthesis of low‐cost microporous activated carbon adsorbents for CO2 capture from Palmyra palm fruit shell waste biomass

AbstractUsing chemical activation techniques at dissimilar carbonization temperatures, activated carbon adsorbents were produced from Palmyra palm fruit biomass in this work. X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, laser Raman spectroscopy, scanning electron microscopy, CHNS‐elemental analysis, and N2 adsorption studies were among the characterization techniques used to assess the characteristics of the carbon adsorbents. The carbon adsorbents from Palmyra palm fruit were used to absorb CO2 in a temperature range of 25–70°C. The findings of the characterization showed that these carbons have a large surface area and microporosity. The temperature of carbonization and the activating agent had an impact on the surface characteristics. The samples with the highest adsorption capacity, 4.70 mmol/g at 25°C, were the activated carbons made by treating them with KOH and then carbonizing them at 750°C. The physicochemical properties of the adsorbents provided an explanation for their high adsorption capacity. The adsorbents showed simple desorption and maintained constant activity during ten cycles of recycling.

Enhancing Sustainable Production of Biodiesel from Xanthoceras sorbifolia Bunge Oil Using Bio-Based Heterogeneous Catalyst

The swift exhaustion of natural oil reserves and worsening environmental issues have prompted the quest for an economical method to produce biofuels. The superiority of heterogeneous catalysis promotes the development of bio-based catalysts. Carbon materials prepared from agricultural and forestry biomass waste have good application prospects in catalysis. In the present study, Xanthoceras sorbifolia shell waste was used as the raw material, Xanthoceras sorbifolia Bunge Carbon (XC) was used as the catalyst carrier, and K2CO3 was used as the activator to prepare a heterogeneous catalyst (KXC). The heterogeneous catalyst was characterized by scanning electron microscopy-energy dispersion X-ray spectroscopy (SEM-EDS), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) and X-ray photoelectron spectroscopy (XPS) analysis techniques to evaluate its chemical composition, structure, and physical morphology. EDS and XPS revealed the presence of K metal, which provided an alkaline site for the transesterification reaction to produce biodiesel. The biodiesel yield was observed by gas chromatography−mass spectrometry (GCMS). Under the reaction conditions of a methanol-to-oil molar ratio of 12:1, a reaction time of 90 min, a temperature of 65 °C, and a catalyst loading of 4 wt.% using 25KXC-600-4, the yield of biodiesel can reach 95.13 ± 0.82%. After being repeated five times, the yield was still 58.11 ± 3.80%. The catalyst has no waste generation, and has the characteristics of simple preparation and environmental friendliness, which make it a green heterogeneous catalyst for biodiesel production.