Free fatty acids

In this study, acetaldehyde, acetone, pH, titratable acidity, lactic acid, tyrosine and free fatty acids, namely butyric acid (C4), caproic acid(C6), caprylic acid (C8) and capric acid (C10) were taken into consideration affecting the variation in aroma and flavour scores (AFS) of strained yoghurt during the storage period of 60 days. AFS was negatively correlated with acetone (r=-0.832, P<0.01) and positively correlated with C4 (r=0.604, P<0.05), C8 (r=0.638, P<0.01) and C10(r=0.659, P<0.01). The results of regression analysis verified that the independent compounds explain the 91.6% of variation in AFS during the storage period, but not statistically significant (P>0.05). Stepwise regression procedure was performed to select the statistically significant compounds affecting AFS. The Stepwise procedure verified that acetaldehyde, acetone and lactic acid should be included in the regression equation (r 2 =0.868, P<0.01). To explore the individual direct effect of t...

[AMAZON LINK BELOW TO BOOK ITSELF -- TOC and book summary in downloadable .pdf] 

In the modern jungle of burgers, couches, and remote controls, obesity is an enormous and growing epidemic. Weight-loss books and diet gurus urge us to "listen to our bodies," but our instincts are designed for the African savannah, not food courts. The sugary and fatty foods that we, as hunter-gatherers, are programmed to forage used to be hard to come by. Now they're as close as the vending machine down the hall.

Radical changes are necessary and, fortunately, are biologically easier than small or gradual changes in diet. Barrett tells us how to reprogram our bodies, break food addictions, and ignore our attraction to "supernormal stimuli"—artificial creations that appeal to our instincts more than the natural objects they mimic. Barrett delves into scientific research—from animal ethology to evolution—to show the disastrous direction in which our instincts have led us, and how, using our intellect, we can get back on course.  . . . . . . . .An elegantly written and eye-opening analysis of what makes us fat. -- Steven Pinker, PhD, Johnstone Professor of Psychology, Harvard University, and author of How the Mind Works
. . . . . . .
In this cogent, clearly argued, and thought-provoking book, Barrett shows how we are paying the price for our own plenty. -- David Spiegel, M.D. Medical Director, Center for Integrative Medicine, Stanford University School of Medicine; author of Living Beyond Limits
. . . . . . . .
Offers us a way to understand the pandemic of obesity that we find ourselves in. -- John Ratey, M.D. Clinical Associate Professor of Psychiatry Harvard Medical School, co-author of Driven to Distraction

— The rising market in biofuels has been encouraging researchers to develop new routes for biodiesel production in order to increase the yields of the process. Heterogeneous acid catalysts represent an alternative to avoid the traditional alkaline pathway for producing alkyl esters from oils with a high content of free fatty acids. In this study, sulfated-niobium oxide catalyst was developed by impregnating Nb 2 O 5 with H 2 SO 4 (0.5 mol/L) and used to carry out simultaneous esterification and transesterification of andiroba (Carapa guianensis) oil with high free fatty acid content (acid value: 33.1 mg KOH/g). Reactions were performed with anhydrous ethanol under different conditions of temperature and molar ratio of oil to ethanol, using the SO 4 2-/Nb 2 O 5 , catalyst at 5% (w/w reaction mixture). The oil conversion was determined by the 1H-NMR spectroscopy method and the maximum conversion of andiroba oil into ethyl esters was 90.9%, which was achieved in a pressurized reactor. Keywords— Acid oil, esterification/transesterification, ethyl esters, free fatty acids, niobium oxide-sulfate.

A carbonization-sulfonation method was utilized in synthesizing sulfonated mesoporous catalysts from palm tree biomass. Brunauer-Emmet-Teller (BET), powder X-ray diffraction (XRD), energy dispersive X-ray (EDX), and field emission scanning emission microscopy (FE-SEM) analyses were used to evaluate the structural and textural properties of the catalysts. Further, Fourier transform infrared (FT-IR) spectroscopy and titrimetric analyses measured the strong acid value and acidity distribution of the materials. These analyses indicated that the catalysts had large mesopore volume, large surface area, uniform pore size, and high acid density. The catalytic activity exhibited by esterifying used frying oil (UFO) containing high (48%) free fatty acid (FFA) content further indicated these properties. All catalysts exhibited high activity, with sPTS/400 converting more than 98% FFA into fatty acid methyl esters (FAMEs). The catalyst exhibited the highest acid density, 1.2974 mmol/g, determined by NaOH titration. This is outstanding considering the lower reaction parameters of 5 h, 5:1 methanol-to-oil ratio, and a moderate temperature range between 100 and 200 degrees C. The study further illustrates the prospect of converting wastes into highly efficient, benign, and recyclable solid acid catalysts.

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http://www.ncsu.edu/bioresources/BioRes_10/BioRes_10_2_3393_Sani_RAAW_Palm_Frond_Spikelet_Catal_Biodiesel_6824.pdf

An industrial grade acidic crude palm oil (ACPO) pre-treatment process was carried out using ethanesulfonic acid (ESA) as a catalyst in the esterification reaction. ESA was used in different dosages to reduce free fatty acid (FFA) to a minimum level for the second stage of biodiesel production via alkaline transesterification reaction. Different process operating conditions were optimized such as ESA dosage (0.25–3.5% wt/wt), methanol to ACPO molar ratio (1:1–20:1), reaction temperature (40–70 °C), and reaction time (3–150 min). This study revealed the potential use of abundant quantities of ACPO from oil palm mills for biodiesel production. The lab scale results showed the effectiveness of the pre-treatment process using ESA catalyst. Three consecutive catalyst recycling runs were achieved without significant degradation in its performance. Second and third reuse runs needed more reaction time to achieve the target level of FFA content. Esterification and transesterification using ESA and KOH respectively is proposed for biodiesel industrial scale production. The produced biodiesel meets the international standards specifications for biodiesel fuel (EN 14214 and ASTM D6751).► Acidic crude palm oil is proposed as a raw material for biodiesel production. ► Ethanesulfonic acid is introduced as a new esterification catalyst. ► The acid was recycled for three batches with insignificant lose in efficiency. ► The produced biodiesel meets the international standards for biodiesel fuel.

A Taguchi orthogonal array was used to investigate the effects of catalyst type, catalyst concentration, temperature and methanol to oil molar ratio on the heterogeneous esterification of free fatty acids (FFA) in waste cooking oil (WCO) using ion-exchange resins. Analysis of Variance (ANOVA) was also applied to study the final FFA conversion in response to the investigated factors. The F-test indicated that catalyst type and methanol:oil molar ratio significantly influenced the FFA conversion. The optimal parameters of FFA esterification in WCO using ion-exchange resins obtained within the experimental ranges studied are as follows: Catalyst Amberlyst-15 at 4 wt.%, temperature of 65 °C and a methanol to oil molar ratio of 15:1. Under these conditions, a maximum FFA conversion of 60.2% could be obtained. The kinetics of the optimised FFA esterification catalysed by 4 wt.% Amberlyst-15 fitted well to a Langmuir–Hinshelwood (L–H) based model.

Context: Caesalpinia bahamensis Lam. is a medicinal plant used by the Cuban population to treat renal and hepatic diseases. However, this species lacks scientific studies that support its biological applications. Aims: To evaluate the chemical composition and the antioxidant capacity of fractions obtained from the stem of Caesalpinia bahamensis Lam. Methods: A continuous extraction of the stem was made by maceration using a battery of solvents of increasing polarity: chloroform, ethyl acetate and methanol. All fractions were analyzed by TLC and phytochemical screening. The compounds of the chloroform fraction were identified by GC/MS, while the ethyl acetate and methanol fractions were characterized by UV-Vis spectroscopy. The antioxidant capacity was evaluated by the DPPH and FRAP assays. Results: Ten compounds were identified by GC/MS of the chloroform fraction, associated with fatty acids, terpenoids and phytosterols. The major compounds of this fraction were octacosanol, monopal...

Non-alcoholic fatty liver disease (NAFLD) and Non-alcoholic steatohepatitis (NASH)
are associated with cardiovascular events and Metabolic Syndrome (MetS). NAFLD is considered to be a hepatic manifestation of MetS and has become an important public health issue
because of its high prevalence. It is currently being considered an independent Cardiovascular
disease (CVD) risk factor. In this clinical review, we will briefly review the mechanisms linking
NAFLD to the complement system, endothelial dysfunction and the atherosclerosis.

G protein-coupled receptor (GPCR) (also known as seven-transmembrane domain receptor) superfamily represents the largest protein family in the human genome. These receptors respond to various physiological ligands such as photons, odors, pheromones, hormones, ions, and small molecules including amines, amino acids to large peptides and steroids. Thus, GPCRs are involved in many diseases and the target of around half of all conventional drugs. The physiological roles of free fatty acids (FFAs), in particular, long-chain FFAs, are important for the development of many metabolic disease including obesity, diabetes, and atherosclerosis. In the past half decade, deorphanization of several GPCRs has revealed that GPR40, GPR41, GPR43, GPR84 and GPR120 sense concentration of extracellular FFAs with various carbon chain lengths. GPR40 and GPR120 are activated by medium- and long-chain FFAs. GPR84 is activated by medium- chain, but not long-chain, FFAs. GPR41 and GPR43 are activated by short-chain FFAs. GPR40 is highly expressed in pancreatic beta cells and plays a crucial role in FFAs-induced insulin secretion. GPR120 is mainly expressed in enteroendocrine cells and plays an important role for FFAs-induced glucagon-like peptide-1. GPR43 is abundant in leukocytes and adipose tissue, whilst GPR41 is highly expressed in adipose tissue, the pancreas and leukocytes. GPR84 is expressed in leukocytes and monocyte/macrophage. This review aims to shed light on the physiological roles and development of drugs targeting these receptors.

In this study, the reduction of free fatty acid (FFA) in low grade palm oil (LGPO) was conducted at various sonication times, ranging from 30 to 300. min. Screening of various acids was reported and selected acid was considered for further study. The results found that strong acids such as sulfuric acid to be superior to other acids. The FFA content of LGPO decreased from 20% to less than 3%, using sulfuric acid at optimum conditions. Treated LGPO can be used as a new type of fuel for various applications such as biodiesel production. © 2013 The Korean Society of Industrial and Engineering Chemistry.

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www.sciencedirect.com/science/article/pii/S1226086X1300453X

The enormous challenges faced in the search for suitable and profitable feedstocks to produce biodiesel cannot be over-emphasis. This paper has provided an overview of different catalysts used in processing different kinds of feedstocks for the production of biodiesel. Although the process of biodiesel production from refined feedstocks is less cumbersome and could provide biodiesel yield of more than 98%, but its product cost is high. Thus, the recent biodiesel production from low-quality feedstocks, though presents challenges but has equally provided biodiesel yield comparable to that obtained from refined feedstocks. Furthermore the physicochemical properties of biodiesel derived from low-quality feedstocks are discussed. Additionally economic evaluation of biodiesel from low-quality feedstocks is examined. The result showed that if less expensive feedstocks are used to produce biodiesel, a 25% reduction in cost production is possible. Thus making biodiesel price reasonably close...

Context: Caesalpinia bahamensis Lam. is a medicinal plant used by the Cuban population to treat renal and hepatic diseases. However, this species lacks scientific studies that support its biological applications.

Aims: To evaluate the chemical composition and the antioxidant capacity of fractions obtained from the stem of Caesalpinia bahamensis Lam.

Methods: A continuous extraction of the stem was made by maceration using a battery of solvents of increasing polarity: chloroform, ethyl acetate and methanol. All fractions were analyzed by TLC and phytochemical screening. The compounds of the chloroform fraction were identified by GC/MS, while the ethyl acetate and methanol fractions were characterized by UV-Vis spectroscopy. The antioxidant capacity was evaluated by the DPPH and FRAP assays.

Results: Ten compounds were identified by GC/MS of the chloroform fraction, associated with fatty acids, terpenoids and phytosterols. The major compounds of this fraction were octacosanol, monopalmitin and palmitic acid. The presence of flavonoids in the ethyl acetate and methanol fractions was demonstrated by phytochemical screening, TLC and UV spectroscopy. The three fractions showed antioxidant capacity in the DPPH assay, with the methanol fraction (IC50=11.1 µg/mL) being the most active. The ethyl acetate fraction (equivalent to 100.7 µmol ascorbic acid) and the methanol fraction (equivalent to 37.3 µmol ascorbic acid) showed antioxidant capacity in the FRAP assay at concentrations of 125 µg/mL and 1000 µg/mL, respectively.

Conclusions: The fractions evaluated showed antioxidant capacity in the DPPH and FRAP assays, possibly associated with the presence of phenols and flavonoids.

In this study low grade crude palm oil (LGCPO) was proposed as a potential agro-industrial raw material for biodiesel production. Chromosulfuric acid was used as a new homogenous catalyst in the pre-treatment process to reduce the free fatty acids (FFA) content in LGCPO to the acceptable level for producing biodiesel via alkaline transesterification reaction. The results of esterification reaction showed

Mixed industrial palm oil (MIPO) is proposed in this study as a renewable and agro-industrial raw material to produce biodiesel fuel. MIPO was obtained by mixing of acidic crude palm oil with sludge palm oil. Due to the high level of free fatty acid (FFA) in MIPO (8.5 %), esterification is needed to remove the acidity to the minimum level before biodiesel production. This is the first time 1-propanesulphonic acid (1-PSA) has been introduced as a catalyst for the pretreatment of MIPO. Using optimum conditions, the FFA content was successfully reduced from 8.5 % to less than 1 %. The biodiesel produced meets the international standards (ASTM D6751 and EN 14214). 1-PSA is therefore a promising catalyst that can be used to treat various types of acidic oils.

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http://repository.um.edu.my/91240/1/BioEnergyRes.pdf

An industrial grade acidic crude palm oil (ACPO) pre-treatment process was carried out using ethanesulfonic acid (ESA) as a catalyst in the esterification reaction. ESA was used in different dosages to reduce free fatty acid (FFA) to a minimum level for the second stage of biodiesel production via alkaline transesterification reaction. Different process operating conditions were optimized such as ESA dosage (0.25-3.5% wt/wt), methanol to ACPO molar ratio (1:1-20:1), reaction temperature (40-70°C), and reaction time (3-150. min). This study revealed the potential use of abundant quantities of ACPO from oil palm mills for biodiesel production. The lab scale results showed the effectiveness of the pre-treatment process using ESA catalyst. Three consecutive catalyst recycling runs were achieved without significant degradation in its performance. Second and third reuse runs needed more reaction time to achieve the target level of FFA content. Esterification and transesterification using ESA and KOH respectively is proposed for biodiesel industrial scale production. The produced biodiesel meets the international standards specifications for biodiesel fuel (EN 14214 and ASTM D6751). © 2011 Elsevier Ltd.

http://ac.els-cdn.com/S096085241101025X/1-s2.0-S096085241101025X-main.pdf?_tid=94bdf038-0ca1-11e4-905d-00000aab0f27&acdnat=1405485065_c5dc472305b417258ef704d5ecf5cda6 
http://www.ncbi.nlm.nih.gov/pubmed/21855329 
http://www.sciencedirect.com/science/article/pii/S096085241101025X

Plant oils having lower levels of percent Free Fatty Acids (%FFAs) moieties offer particular potentials in
evaluation of qualities of liquid biofuels, because they are associated with reduction of atmospheric pollution
relative to petroleum diesel fuel. The present study examined effects of FFAs on the quality of Euphorbia
tirucalli (L.) oil extracted from different stem diameters such as 20cm, 30cm, 40cm, 50cm, 60cm, 70cm and
80cm. Soxhlet extraction method was used in oil extraction. Acid Values (AVs) were determined by standard
methods ASTM D 664 and the Cd 3d-63 of the American Society for Testing and Materials and the American
Oil Chemists Society respectively. The AVs so obtained were used to calculate the amount of FFA contents in
E. tirucalli oil as percent oleic acid. One-way ANOVA with the Minitab software v.16 was used to test for
differences in %FFAs. The %FFA contents of the oil were compared with the international quality biofuel
standard ASTM D 6751 (0.020max). Results showed that the quality of oil which was expressed in terms of
%FFAs of oil ranged from 4.57 + 0.02 at 20cm to 4.72 + 0.02 at 40cm, 3.61 + 0.10 at 40cm to 4.42 + 0.10 at
30cm and 2.45 + 0.07at 30cm to 3.06 + 0.07 at 60cm stem diameters from Dodoma, Mbeya and Dar es Salaam
agro-ecological zones in the same order. These results indicated low quality of oil since the entire %FFAs were
above 0.020max%, not complying with the ASTM D 6751 standard. Also the obtained %FFAs of oils differed
significantly (P ≤ 0.05) among different stem diameters and agro-ecological zones. The study concluded that the
quality of oil (%FFAs) was low and found to decrease from low to high stem diameters of E. tirucalli in
different agro-ecological zones.

In this study low grade crude palm oil (LGCPO) was proposed as a potential agro-industrial raw material for biodiesel production. Chromosulfuric acid was used as a new homogenous catalyst in the pre-treatment process to reduce the free fatty acids (FFA) content in LGCPO to the acceptable level for producing biodiesel via alkaline transesterification reaction. The results of esterification reaction showed

"The yellow greases and the vegetable oils used can be converted to biodiesel. The
problem with these sources of low cost oil and fats is that they contain large amounts
of free acids that cannot be converted to biodiesel using an alkaline catalyst. A
pretreatment to avoid the formation of soaps is an acid-catalyzed to esterify the free fatty acids before transesterifying the triglycerides with an alkaline catalyst to complete the reaction. The best production of biodiesel, corresponds to the methyl oleate, with 4.985 kmol/hr, and for the methyl butyrate a production of 4.658 is obtained kmol/hr."

In this study low grade crude palm oil (LGCPO) was proposed as a potential agro-industrial raw material for biodiesel production. Chromosulfuric acid was used as a new homogenous catalyst in the pre-treatment process to reduce the free fatty acids (FFA) content in LGCPO to the acceptable level for producing biodiesel via alkaline transesterification reaction. The results of esterification reaction showed that the FFA of LGCPO was reduced from 7.0 % to less than 1% using optimum operating conditions. The yield of the final product after the alkaline transesterification was 85% with 0.14 % FFA content and ester content 97.5% (mol mol-1) which meets the international standard quality specifications for biodiesel. © 2013 Bulgarian Academy of Sciences, Union of Chemists in Bulgaria.

www.bcc.bas.bg/bcc_volumes/Volume_45_Number_3_2013/Volume_45_Number_3_2013_PDF/BCC-45-3-394-399.pdf

Heterogeneous catalysts are promising for the transesterification reaction of vegetable oils to produce biodiesel. Unlike homogeneous, heterogeneous catalysts are environmentally benign and could be operated in continuous processes. Moreover they can be reused and ...

Heterogeneous catalysts are promising for the transesterification reaction of vegetable oils to produce biodiesel. Unlike homogeneous, heterogeneous catalysts are environmentally benign and could be operated in continuous processes. Moreover they can be reused and regenerated. However a high molar ratio of alcohol to oil, large amount of catalyst and high temperature and pressure are required when utilizing heterogeneous catalyst to produce biodiesel. In this paper, the catalytic activity of several solid base and acid catalysts, particularly metal oxides and supported metal oxides, was reviewed. Solid acid catalysts were able to do transesterification and esterification reactions simultaneously and convert oils with high amount of FFA (Free Fatty Acids). However, the reaction rate in the presence of solid base catalysts was faster. The catalyst efficiency depended on several factors such as specific surface area, pore size, pore volume and active site concentration. © 2009 Elsevier B.V. All rights reserved.

http://ac.els-cdn.com/S0378382009000629/1-s2.0-S0378382009000629-main.pdf?_tid=944422d4-2363-11e4-be00-00000aacb362&acdnat=1407987312_4885f84527f97d6f59c2ddefc0defb50 
http://www.sciencedirect.com/science/article/pii/S0378382009000629

Homogeneous acid catalysts received wide acceptability because of their fast reaction rates. However, postproduction costs incurred from aqueous quenching, wastewater and loss of catalysts led to the search for alternatives. Until recently, heterogeneous base catalyzed-biodiesel production also gained the attention of most researchers. This was because the process minimized the problems of homogeneous catalysis in terms of catalyst regeneration and recycling in continuous processes. However, despite these advances, the ultimate aim of producing biodiesel at affordable cost is yet to be realized. Further, the process requires refined feedstocks which account for as high as 88% of the final production costs. Thus, the focus of many research efforts is towards the rational design and development of solid acid catalysts aimed at reducing biodiesel production costs. Therefore, this study reviewed current literature on the activities and advantages of solid acid catalysts used in biodiesel production. It discussed in details how the preparation method and prevailing reaction conditions affect the catalytic activity of the catalyst. The review concluded by suggesting way forward from the traditional trial-and-error method to a rational means of determining catalytic activities. © 2013 Elsevier Ltd. All rights reserved.

http://ac.els-cdn.com/S0926860X13006716/1-s2.0-S0926860X13006716-main.pdf?_tid=8e1e1ab8-2363-11e4-9ca9-00000aab0f6c&acdnat=1407987302_a3cdc78dacadf0ac81270c4872c97b97 
http://www.sciencedirect.com/science/article/pii/S0926860X13006716

Industrial low-grade crude palm oil (LGCPO) generated from industrial palm oil mills must be pretreated before utilizing it as a biodiesel raw material. The pretreatment of LGCPO was conducted using benzenesulfonic acid (BZSA) as solid organic acid catalyst. Batch pretreatment of LGCPO was carried out to study the influence of BZSA dosage (0.25 - 3.5% wt/wt), methanol molar ratio to LGCPO (4:1 - 20:1), temperature (40 - 80°C), and reaction time (3 - 150 min). The effects of those parameters on the free fatty acid content, and the yield of pretreated LGCPO were reported. This study illustrated the feasibility of using LGCPO from palm oil mills to produce biodiesel. The biodiesel produced from LGCPO meets the international standards (ASTM D6751 and EN 14214). Three times recycling of BZSA was achieved without appreciable degradation in its activity. This study introduces a possible batch esterification process using BZSA followed by an alkaline transesterification reaction for a possible future industrial application. © 2014 Copyright Taylor and Francis Group, LLC.

http://www.tandfonline.com/doi/pdf/10.1080/15435075.2013.770397

Energy is fundamental to the quality of life in the earth. Meeting the growing demand for energy sustainably is one of the major challenges of the 21st century. Indonesia is a developing country and the world's fourth most populous nation. Total annual energy consumption increased from 300,147 GWh in 1980, 625,500 GWh in 1990, 1,123,928 in 2000 and to 1,490,892 in 2009 at an average annual increase of 2.9%. Presently, fossil-fuel-based energies are the major sources of energy in Indonesia. During the last 12 years, Indonesia has recorded the most severe reduction in fossil fuel supplies in the entire Asia-Pacific region. This reduction has stimulated promoting the usage of renewable energy resources capable of simultaneously balancing economic and social development with environmental protection. Biodiesel is an alternative and environmentally friendly fuel that will participate in increasing renewable energy supply. Jatropha curcas is one of biodiesel resources that offer immediate and sustained greenhouse gas advantages over other biodiesel resources. Globally, J. curcas has created an interest for researchers because it is non-edible oil, does not create a food versus fuel conflict and can be used to produce biodiesel with same or better performance results when testing in diesel engines. The present study is concerned with the prospect of biodiesel produced from J. curcas in Indonesia. The first part gives a summary and overview of energy resources and consumption in the country, second part discusses the potential of biodiesel as a powerful renewable energy resource and third part investigates the potential of J. curcas as a feedstock for biodiesel in Indonesia. The final part discusses the development of biodiesel market in Indonesia. The paper found out that the production of biodiesel from J. curcas offers many social, economical and environmental benefits for the country and can play a great role to solve the problem of energy crisis in Indonesia. © 2011 Elsevier Ltd. All rights reserved.

http://ac.els-cdn.com/S1364032111002462/1-s2.0-S1364032111002462-main.pdf?_tid=cfec532c-4a85-11e3-93d8-00000aab0f01&acdnat=1384142614_632225ceb793e8f3731faa800dfe3ae9 
www.mdpi.com/1996-1073/6/1/128/pdf

An industrial grade acidic crude palm oil (ACPO) pre-treatment process was carried out using ethanesulfonic acid (ESA) as a catalyst in the esterification reaction. ESA was used in different dosages to reduce free fatty acid (FFA) to a minimum level for the second stage of biodiesel production via alkaline transesterification reaction. Different process operating conditions were optimized such as ESA dosage (0.25–3.5% wt/wt), methanol to ACPO molar ratio (1:1–20:1), reaction temperature (40–70 °C), and reaction time (3–150 min). This study revealed the potential use of abundant quantities of ACPO from oil palm mills for biodiesel production. The lab scale results showed the effectiveness of the pre-treatment process using ESA catalyst. Three consecutive catalyst recycling runs were achieved without significant degradation in its performance. Second and third reuse runs needed more reaction time to achieve the target level of FFA content. Esterification and transesterification using ESA and KOH respectively is proposed for biodiesel industrial scale production. The produced biodiesel meets the international standards specifications for biodiesel fuel (EN 14214 and ASTM D6751).► Acidic crude palm oil is proposed as a raw material for biodiesel production. ► Ethanesulfonic acid is introduced as a new esterification catalyst. ► The acid was recycled for three batches with insignificant lose in efficiency. ► The produced biodiesel meets the international standards for biodiesel fuel.