Free Fatty Acids In Oil Research Articles

Biomass-incorporated KNO3-C/γ-Al2O3 bifunctional catalyst for efficient biodiesel production

Biodiesel has gained attention as a promising renewable and sustainable alternative to fossil fuels, which necessitated the development of an effective and eco-friendly catalyst for transesterification processes. Herein, this research reported the development of a highly efficient bifunctional catalyst by incorporating carbon from oil palm leaves (OPLs) into KNO3/γ-Al2O3 catalyst, synthesized through a facile method, to concurrently catalyze the waste cooking oil (WCO) transesterification and free fatty acids (FFAs) esterification in a one-pot reaction. Proposed Box-Behnken Design (BBD) model's ideal conditions, experimentally yielded an average of 93.74 % biodiesel yield. Meanwhile, analysis revealed that the catalyst with 30 wt% KNO3 loadings and 1.0 g oil palm leaves dosage (OPLD), calcined at 700 °C, has a BET surface area of 46.93 m2/g and exhibited the presence of K2O, K2O2 and K2C2 active species on the catalyst surface. In addition to exhibiting high total basicity and acidity of 2.9 mmol/g and 2.1 mmol/g, respectively, environmental studies suggested this catalyst generated less waste, highlighting its significant potential of being used for efficient biodiesel production. Therefore, present research introduces a new approach for synthesizing a fruitful and ecofriendly bifunctional catalyst to attain one-pot biodiesel production from low-grade oils.

Enzymatic conversion of camellia seed oil into glycerol esters: Synthesis and characterization

AbstractThe conversion of triacylglycerols in edible oils into diacylglycerols (DAGs) is of great significance for obtaining products with health benefits. Camellia seed oil (C‐oil), which is rich in oleic acid and linoleic acid, is an excellent raw material for the production of DAGs. In this study, single factor optimization experiments were carried out for hydrolysis and esterification respectively. Using Lipozyme® RM IM as catalyst, the maximum percent of C‐oil hydrolysis reached 87.14% at the reaction temperature of 60°C, reaction time of 24 h, water content of 30% and enzyme addition amount of 4%. The maximum content of camellia seed oil diacylglycerol (C‐DAG) reached 62.49% under the conditions of Lipozyme® RM IM as catalyst, vacuum system, 3% enzyme addition, 2% water addition, reaction temperature of 50°C and substrate molar ratio of free fatty acid to glycerol of 1:1. The high content of DAG was obtained by a coupled method, which eliminated the purification steps and reduced production costs. C‐oil and C‐DAG have been characterized by GC, TG, DSC, and GC‐IMS. Our results showed that the enzymatic coupling method did not affect the structural of the substances, but did affect the crystallization and melting properties of the oils. Moreover, the taste of C‐DAG was more delicate than C‐oil. Finally, the reaction mechanism was analyzed using FTIR spectroscopy, revealing that C‐oil was primarily hydrolyzed into free fatty acids. C‐DAG exhibited ester C‐O stretching vibrations in the range 1280–1030 cm−1, indicating successful esterification reaction between camellia seed oil free fatty acids (C‐FFAs) and glycerol catalyzed by lipases.

In–situ modification of UiO–66(Zr) organic ligand to synthesize highly recyclable solid acid for biodiesel production

To transfer high free fatty acid oil into biodiesel in mild conditions is still facing challenge, thereinto, the key is efficient acid catalyst. In this study, 2,5–dimercaptoterephthalic acid was adopted to substitute terephthalic acid as ligand for UiO–66–(SH)2 synthesis, then the sulfydryl (–SH) was in-situ oxidized by hydrogen peroxide and acidified via sulfuric acid thus generating sulfonic catalyst UiO–66–(SO3H)2. To further reveal the relationship between physico–chemical property and catalytic activity, catalyst was characterized via thermogravimetry analysis (TG), X–ray diffraction (XRD), N2 absorption–desorption, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and pyridine absorption–Fourier transform infrared spectroscopy (Py–FTIR). Results indicate the in–situ modification increases the quantity of acid sites for UiO–66(Zr), where the acidity is aggrandized from 0.02 mmol/g to 2.28 mmol/g. The maximum conversion of oleic acid to biodiesel was 86.52 % with catalyst amount of 10 wt% and molar ratio of methanol/oleic acid of 15 at 90 °C within 4 h. Moreover, UiO–66–(SO3H)2 exhibited favorable reusability and water resistance, which maintained an excellent esterification conversion after four cycles and no obvious impact was detected as the water content was 10 wt%. The quality of obtained biodiesel in this study satisfied the European Union standard of EN 14214, which could be used as transport fuel.

Enhanced Mixing Towards the Production of Fatty Acid Methyl Esters by In Situ Transesterification of Eucheuma Cottonii: Experimental and Computational Fluid Dynamics (CFD) Analysis

Biodiesel is one of the alternative replacements for the conventional fossil fuel-based diesel as the demand for energy is increasing with the increasing world population. The production of biodiesel (also known as fatty acid methyl esters (FAME)) from macroalgae (E. cottonii) is the focus in this study. Conventionally, production of FAME from macroalgae will be carried out through the two-step transesterification processes, which consists of extraction of algal oil (lipids and free fatty acids) and subsequent transesterification step. However, the two-step transesterification method is time and energy consuming processes and thus ways to enhance the production yield of the biodiesel produced are being studied. This paper concentrates on utilization of enhanced mixing technique via in situ transesterification (ISTE) process in FAME production which elucidate the effects of reaction time and mixing intensity. The ISTE reaction was carried out at the ratio of biomass: Methanol (MeOH): Hydrochloric Acid (HCl) (w/v/v) of 1:20:5 and a reaction temperature of 60 °C. The total reaction time for the reaction was 90 minutes, where samples were collected at 30 minutes interval. The increase in reaction time and mixing intensity gave a significant positive impact on the production of FAME. At 90 minutes of reaction time and impeller rotational speed of 900rpm, the maximum amount of methyl palmitate and methyl stearate produced were 0.5729 wt% and 0.0559 wt% respectively. The results of contour of volume fraction (VF) of palmitic acid obtained from Computational Fluid Dynamics (CFD) analysis from the Aspen Fluent Software is in good agreement to the experimental results of the study.

Penggunaan Arang Aktif Ampas Kopi untuk Menurunkan Bilangan Peroksida dan Asam Lemak Bebas (ALB) pada Minyak Goreng Bekas

The peroxide value and free fatty acid content influence the quality of cooking oil. Activated charcoal from coffee grounds has been used in processing used cooking oil. This research aimed to determine the ratio of coffee grounds activated charcoal adsorbent-to-used cooking oil (w/v) and the optimum contact time to reduce used cooking oil's peroxide and free fatty acid levels. The ratio of adsorbent and used cooking oil was 1:20, 1:10, and 1:5 (w/v) with contact times of 60, 90, and 120 minutes. Coffee grounds charcoal was activated by ZnCl2. A ratio of adsorbent and cooking oil 1:5 (10 g activated carbon and 50 ml cooking oil) reduced the peroxide number from 12 mek/O2 kg to 9.8 mek/O2 kg and free fatty acids from 0.972% to 0.383%. A contact time of 120 minutes could optimally reduce the peroxide number and free fatty acids from 12 mek O2/kg to 9.3 mek O2/kg and 0.972% to 0.332%, respectively. Coffee grounds have the potential to be processed into activated charcoal for refining used cooking oil.

Hierarchical porous SAPO-34 decorated with Mo and W oxides for concurrent transesterification-esterifications for efficient biodiesel production from acidic soybean oil

Hierarchical porous materials have gained much attention as promising heterogeneous catalyst supports due to their high efficiency of mass transfer and high exposure of active centers. In this research, the hierarchical porous SAPO-34 support with microporous, mesoporous, and macroporous hierarchical structure was initially prepared by in-situ alkali etching. Then, Mo and W oxides were incorporated into this hierarchical porous support by using the impregnation method to prepare Mo15W15/HSAPO-34/70 catalyst. This developed catalyst was applied to concurrently catalyze the oil transesterification and free fatty acid (FFA) esterification to biodiesel as the low-value oils severed as feedstocks. The textural and physicochemical properties of the nanocatalysts were evaluated by XRD, XPS, SEM, EDS, TEM, UV–vis, NH3-TPD, Py-FTIR, and nitrogen porosimetry measurement. This catalyst had hierarchical porous structure to ameliorate the large oil molecular transfer, and featured dual Brønsted-Lewis acid sites to synergistically boost the catalytic efficiency for the biodiesel production. Over this catalyst, the oil conversion of 90.1 % and full FFA conversion were achieved under optimized operation conditions, therefore imparting to one-pot conversion to biodiesel with low-value oils as feedstocks. In addition, this catalyst not only exhibited superior tolerance to moisture and FFAs, but also retained high activities after five reuse cycles, thus revealing its tremendous potential of being used in durable and efficient biodiesel production. The present work opens a new avenue for synthesizing a robust solid acid catalyst to achieve a one-pot biodiesel production from low-value oils.

The Effect of Yeast Dose and Fermentation Time on the Quality of Virgin Coconut Oil (VCO)

Coconut are tropical plants and can be easily found in Indonesia. Virgin Coconut Oil (VCO) is one of the products produced from coconut beans. VCO is processed using fermentation techniques to maintain its quality and purity. This study aimed to determine the effect of yeast dosage and fermentation time on VCO yield, water content, and free fatty acids. Yeast dosage and fermentation time were the two treatment factors used in this study with a factorial Completely Randomized Design (CRD). To assess the impact of each treatment, the data was analyzed by using ANOVA with the significance level of 95%, followed using the Zeleny method analysis to find the best treatment condition. The oil found in this study was in compliance with SNI 7381:2008 and Asian Pacific Coconut Community (APCC) standards. The effect of yeast dose and fermentation period on oil yield, water content, and free fatty acid content in VCO was significant at α = 0.05. The results of the analysis showed that the best treatment condition was found at a yeast rate of 10 g and a fermentation time of 20 h. This treatment resulted about 15.67% oil yield with 0.2% moisture content and 0.2% free fatty acids. Keywords: Virgin coconut oil; yeast; time; yield; free fatty acid

Adsorptive removal of palm oil free fatty acids onto silica-smectite composite: a statistical study using Box–Behnken design in response surface methodology

Adsorptive removal of palm oil free fatty acids onto silica-smectite composite: a statistical study using Box–Behnken design in response surface methodology

Physicochemical Properties and Biological Activities of Koseret (Lippia adoensis Hochst. Var. Koseret) Seed and Leaf Oil Extracts.

Lippia adoensis Hoechst var. adoensis (wild variety) and variety koseret (cultivated variety) have been used as traditional medicine, condiments, and endemic to Ethiopia. This study aimed to assess the physicochemical properties and biological activities of oil extracts from seed and leaves of koseret (L. adoensis var. koseret). Soxhlet apparatus was used for oil extraction using hexane as a solvent. The oil quality assessment was based on oil yield, acid value, percent free fatty acid, and peroxide value, while the biological activities were investigated based on antioxidant and antimicrobial activities. The antimicrobial experiment was arranged as 2 x1x4 in a completely randomized factorial design with three replications. The result indicated that significantly higher oil yield (2.25%), acid value (2.66%) and free fatty acid (1.34%) were recorded for seed oil using the solvent extraction method. Leaf oil was recorded to have significantly higher values of DPPH (2,2- diphenyl-1- picrylhydrazyl), ascorbic acid and total carotenoid contents, but a lower value of hydrogen peroxide scavenging activity indicated that leaf oil presented higher antioxidant activity than seed oil in koseret. The koseret leaf oil demonstrated stronger antibacterial activity with a maximum zone of inhibition (14.50±0.21 mm), minimum inhibitory concentration (MIC, 0.25 μg/ml) and corresponding minimum bactericidal concentration (MBC, 0.25 μg/ml) against S. aureus. Furthermore, leaf oil has also presented stronger antifungal activity with a maximum zone of inhibition (14.83 mm), MIC (0.25 μg/ml), and minimum fungicidal concentration (MFC, 0.50 μg/ml) against Aspergillus versicolor. It can be concluded from the results of this study that leaf oil extract has demonstrated better biological activities, including both antioxidant and antimicrobial potentials, than seed oil in koseret.

Study and Synthesis of Bio-fuel from Jatropha Vegetable Oil

Abstract: This work has been carried out to produce biodiesel and inspect how the production from Jatropha seeds oil, methanol and using a catalyst as Potassium iodide Aluminium oxide (KI Al2O3). This Methodology dried jatropha seeds ware used. This seed oil is extracted from the jatropha seed by applying the Soxhlet extraction method with methanol as the organic solvent and screw-type mechanical expeller. In the oil free fatty acid content of jatropha seeds oil was 0. 800.i.e.is ≤ 2. After using the transesterification process and the ratio of methanol: oil ratio was 12:1, 0.5 g of catalyst and temperature of the reaction was 60 °C for 4 hours of reaction time with stirring at 600 rpm. The cloud point was 7°C. The pour point was 2°C, density was 0.38 g/cm3 and flash point was 155 °C.

Unsaturated bond recognition leads to biased signal in a fatty acid receptor.

Individual free fatty acids (FAs) play important roles in metabolic homeostasis, many through engagement with more than 40G protein-coupled receptors. Searching for receptors to sense beneficial omega-3 FAs of fish oil enabled the identification of GPR120, which is involved in a spectrum of metabolic diseases. Here, we report six cryo-electron microscopy structures of GPR120 in complex with FA hormones or TUG891 and Gi or Giq trimers. Aromatic residues inside the GPR120 ligand pocket were responsible for recognizing different double-bond positions of these FAs and connect ligand recognition to distinct effector coupling. We also investigated synthetic ligand selectivity and the structural basis of missense single-nucleotide polymorphisms. We reveal how GPR120 differentiates rigid double bonds and flexible single bonds. The knowledge gleaned here may facilitate rational drug design targeting to GPR120.

BIODIESEL PRODUCTION FROM WASTE FISH CANNING OIL USING COCOPEAT ASH CATALYST

Biodiesel is an environmentally friendly alternative fuel for diesel engines. The research studies the extraction process of biodiesel from waste produced by a fish canning factory using a heterogeneous catalyst known as cocopeat ash. The experiment was designed utilizing a completely randomized design with two factorial treatments and four repetitions. The primary factor under investigation was the composition of the catalyst, specifically 3%, 5%, and 7% w/v methanol. The second factor examined was the reaction time of either 60 minutes or 120 minutes. Data analysis revealed variations in density, viscosity, acid number, and Free Fatty Acids (FFA) in fish oil before and after refinement. The treatment that yielded the highest results was A3B2, featuring a catalyst composition of 7% and a reaction time duration of two hours, which achieved an impressive biodiesel yield of 81%. Moreover, several parameters tested for compliance with SNI-04-7182-2015 standards showed positive outcomes. These parameters include a density value measuring 876.3 kg/m³, the flash point around 160°C, iodine number reaching 16.36 g/100g, and heating value 47.47 MJ/Kg.

Sustainable Production of Biodiesel from Novel Non-Edible Oil Seeds (Descurainia sophia L.) via Green Nano CeO2 Catalyst

The current study focuses on the synthesis of Cerium oxide (CeO2) nanocatalyst via Tragacanth Gum (TG) using the wet impregnation method and its application for sustainable biodiesel production from a novel, non-edible Descurainia sophia (L.) Webb ex Prantl seed oil. The D. sophia seed oil has higher oil content (36 wt%) and free fatty acid (FFA) value (0.6 mg KOH/g). Innovative analytical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy, were used to characterize the newly synthesized, environmentally friendly, and recyclable CeO2-TG phytonanocatalyst (FT-IR). The results show that the CeO2-TG phytonanocatalyst was 22 nm in diameter with a spherical shape outer morphology, while the inner structure was hexagonal. Due to low FFA content, the D. sophia seed oil was pretreated and transesterified via a single step. Using varying parameters, the optimized process variables were determined via Response Surface Methodology (RSM). The optimum process values were 8:1 methanol to oil molar ratio, 0.3 wt% catalyst concentration, 90 °C temperature, and reaction time of 210 min with 98% biodiesel yield. The recently created phytonanocatalyst was reliable and effective, with three times reusability in the transesterification reaction. Thin layer chromatography (TLC), FT-IR, gas chromatography–mass spectroscopy (GCMS), and Nuclear magnetic resonance (NMR) analyses were used to characterize the synthesized biodiesel. Physico-chemical properties of D. sophia biodiesel, i.e., Kinematic viscosity (4.23 mm2/s), density (0.800 kg/m3), pour point (−7 °C), cloud point (−12 °C), and flash point (73.5 °C) agree well with international biodiesel standards (ASTM-6751, 951), (EU-14214), and China (GB/T 20828) standards. The results show that the synthesized nanocatalyst demonstrated remarkable stability, indicating a bright future for industrial biodiesel production from low-cost feedstock.

Transesterification of Algae Oil and Little Amount of Waste Cooking Oil Blend at Low Temperature in the Presence of NaOH

The present study describes the single-step transesterification method of biodiesel production from high free fatty acid (FFA) waste cooking oil blended with algae oil using a homogeneous base catalyst. Due to high FFA contents, two step transesterification is needed to convert oil into biodiesel and therefore the high FFA content of waste cooking oil is decreased by blending it with low FFA content algae oil, which would further lead only to single step transesterification of low FFA oil. The design and optimization studies were conducted using Response Surface Methodology (RSM). The box-Behnken design technique is applied to optimize the three process parameters, i.e., catalyst concentration (0–2 wt%), methanol concentration (v/v) (20–60%) and reaction time (60–180 min) at a uniform reaction temperature of 50 °C. The result of the current study indicates that an effective biodiesel yield of 92% can be obtained at the optimized condition of catalyst concentration of 1.5% (w/w), methanol/oil ratio of 21:1 and reaction time of 110 min at a constant reaction temperature of 50 °C. This analysis clearly shows that this study can resolve the storage problem of high FFA oils from different feedstock and RSM can be successfully used to model the reaction to maximize the biodiesel yield.

Optimization of Neem oil esterification using response surface methodology

High production cost of biodiesel as well as food-versus-fuelcrisis within the economy have led to the adoption of non-edible feedstock over edible feedstock, the high FFA associated with the former remains a challenge. Esterifying high free fatty acid (FFA) oil with acid is necessary to avoid soap formation during biodiesel production. Thus, this study evaluated the efficacy of response surface methodology (RSM) in modelling the esterification process for neem seed oil (NSO) with a high FFA catalyzed by sulphuric acid H2SO4. A central composite design (CCD) with two level-three factors (23) was applied to examine the influence of Reaction time (60-120 minutes), Catalyst concentration (1.0-3.0 w/w,%), methanol to oil ratio (0.20-0.60w/w,%) and constanttemperature at 60oC on reduction of the high FFA (4.77%) of neem. The Optimum conditions for the esterification process is 0.67 % FFA at 0.4 Methanol to Oil ratio; 90 min. Reaction Time; and 2 (w/w) % H2SO4Catalyst Concentration. Statistics for the RSM model showed that the correlation coefficient (R2) value (0.9457) is relatively high, close to 1, which is desirable and is in reasonable agreement with the adjusted R2 value (0.8969).

Application of Naive Bayes Algorithm to Analysis of Free Fatty Acid (FFA) Production Based on Fruit Freshness Level

Cooking oil is a basic need for everyone who is used to process food ingredients. The use of cooking oil repeatedly and continuously by heating at high temperatures can increase the free fatty acid levels in the oil. The more the oil is reused, the higher the free fatty acid content. Testing the levels of FFA in oil can be done using the FFA test, because FFA can affect the selling price of CPO when it is marketed. In addition, FFA affects the levels of free fatty acids of CPO. This study aims to determine the analysis of FFA production in palm oil products based on the level of freshness of the fruit. The research was conducted by classifying data mining using the Naïve Bayes Algorithm. The Naïve Bayes algorithm was used to determine whether FFA production had an effect on fruit freshness, fruit quality and fruit soiling. The research was conducted using RapidMiner Studio 9.10 tools. The results of the research from the distribution table show that the value of the FFA attribute obtained 2 conditions, namely super conditions and normal conditions. Where each of these attributes is influenced by the variables of fruit freshness and fruit quality. Probability accuracy results from 60 training data and 40 testing data used are 92.50% for super FFA conditions.

Biomass-derived hydrophobic metal-organic frameworks solid acid for green efficient catalytic esterification of oleic acid at low temperatures

Biodiesel, of great significance, is a promising kind of non-polluting renewable energy that can meet world energy needs. However, the by-product water of esterification reaction used for biodiesel production is not conducive to the positive reaction, and even destroys the activity and structure of the used catalyst. In this study, a renewable solid acid catalyst FDCA/SA-Hf with a degree of hydrophobicity was simply prepared by a solvent-free assembly manner using biomass-based materials. FDCA/SA-Hf was found to be efficient for producing biodiesel from the abundant free fatty acid and nonedible raw oils at a low temperature, and its reaction mechanism was also studied. FDCA/SA-Hf showed stable structural properties and excellent hydrophobic network (131.5°), wherein the chemical grafting of stearic acid improved its Lewis acidity and promoted the adsorption of free fatty acid and the desorption of water. Importantly, as promoted by FDCA/SA-Hf in esterification, a high biodiesel yield reached 98.6% (49 °C, 4.1 wt%, 19.5:1 and 9.5 h). After being easily reused, biodiesel yield still achieved 90% even in the presence of 6 wt% water or after six cycles, which was due to the high hydrophobicity and stability. FDCA/SA-Hf shows great potential in heterogeneous acid-mediated catalytic fields, especially for biodiesel production.

Crude rubber seed oil esterification using a solid catalyst: Optimization by hybrid adaptive neuro-fuzzy inference system and response surface methodology

Esterifying high free fatty acid (FFA) oil with acid is necessary to avoid soap formation during biodiesel production. Thus, this study evaluated the efficacies of response surface methodology (RSM) and adaptive neuro-fuzzy inference system (ANFIS) in modeling the esterification process for crude rubber seed oil (CRSO) with a high FFA catalyzed by dehydrated Fe2(SO4)3. A central composite design (CCD) with three factors and five levels was applied to examine the influence of methanol:CRSO molar ratio (25:1–75:1), Fe2(SO4)3 loading (8–16 wt %), and time (3–4 h) on reduction of the high FFA (22.2%) of CRSO. The performance of the particle swarm optimization (PSO), genetic algorithm (GA), and RSM were assessed in optimizing the process variables. Statistics for the ANFIS and RSM models showed that both could reliably describe the esterification process with low mean relative percent deviation (MRPD) of 1.77 and 4.98; and high coefficients of determination (R2) of 0.9838 and 0.9730, respectively. The optimization results are in this order: ANFIS-PSO, ANFIS-GA, RSM-PSO, RSM, and RSM-GA. The ANFIS-PSO hybrid predicted the best optimal condition as Fe2(SO4)3 loading of 16.97 wt%, methanol:CRSO molar ratio of 44.21:1, and time of 3.39 h with the lowest FFA of 0.56%.

OPTIMIZATION OF PROCESS VARIABLES TO OBTAIN QUALITY SHEA KERNELS FROM SHEA NUT

Shea butter is a product of Shea kernel obtained from Shea tree. It has wide range of applications in pharmaceuticals, confectionaries, chocolates, and soap industries. The use of Shea butter for these applications is largely dependent upon its Free Fatty Acid (FFA) content. The resultant FFA of Shea butter produced from the Shea kernel depends largely upon the process variables applied to the kernel prior to Shea butter production. Poor and inconsistent qualities usually characterize unprocessed Nigerian Shea kernels. Thus, the need to improve Shea kernel quality in Nigeria becomes necessary. This study investigated the effects of optimizing processing factors, responses, development, and analysis of predictive response models of Shea kernel leading to its optimization. Shea fruits that have fallen to the ground were picked and the pulp removed to expose the Shea nut. Effects of Shea Nut Conditioning Period (SNCP), Shea Nut Boiling Duration (SNBD) and Shea Nut Drying Temperature (SNDT) on the FFA of Shea kernel were investigated. The boundary conditions obtained from earlier experiments were used for the Design of Experiment (DOE) by Box-Bekehn method of response surface methodology. Fresh Shea kernels were then processed according to the experimental design and the responses of free fatty acid, peroxide value and percentage oil content determined. The upper, middle and lower limits obtained for SNCP were 1, 6.5, and 12 day respectively, SNBD were 0, 60, and 120 minutes respectively and SNDT were 30, 70, 110 oC respectively. The optimum conditions of SNCP, SNBD and SNDT obtained after the optimization of Shea kernel were respectively 4.0 day, 120 minutes and 86 oC and the corresponding predicted responses of PV, percentage oil content, FFA and desirability were 2.868 meq/kg, 0.628 %, 53.8 5 % and 0.878 respectively. Keywords: Shea-kernel, Shea Nut Conditioning Period, Shea Nut Boiling Duration, Shea Nut Drying Temperature, and Optimization

Glycerolysis of high free fatty acid oil by heterogeneous catalyst for biodiesel production

The most widely used commercial biodiesel production technique, alkali-catalysed transesterification, requires only moderate temperatures and pressures to achieve a more than 98% conversion yield. Unfortunately, oil feedstock's high free fatty acid (FFA) content limits the technology's usefulness. A heterogeneous base catalysed glycerolysis process was investigated in this study to lower the FFA and meet these requirements. The response surface methodology (RSM) based on I-optimal design was used to model and optimize a CaO catalysed glycerolysis reaction under the influence of five reaction variables: temperature (60–180 °C), residence time (30–120 min), FFA concentration (6–50%), catalyst amount (0.4–0.6 wt (g/g)), and Glycerol to Oil ratio (G/O) (1–1.5). The data were fitted in a quadratic model, and R2 of 0.986 was observed, signifying that the model well defined the experimental data. The model was validated by running four replicates of the experiment, and a residual standard error of 2.7% was obtained, indicating the model would accurately predict future observations. The 48.584% FFA in oil was reduced to 0.98% under optimal conditions of 170 °C, 39.9 min of residence time, 0.591 wt g catalyst concentration, and 1.026 g/g glycerol/oil (G/O) ratio. CaO catalysed glycerolysis has significantly reduced FFA to less than 3% in less than an hour in biodiesel feedstock for biodiesel production.