New heterogeneous metal-oxides based catalyst for vegetable oil trans-esterification

Macêdo, Caio C.S.; Abreu, Frederique R.; Tavares, André P.; Alves, Melquizedeque B.; Zara, Luiz Fabrício; Rubim, Joel C.; Suarez, Paulo A. Z.

doi:10.1590/s0103-50532006000700014

Cited by 92 publications

(49 citation statements)

References 20 publications

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“…As result, catalysts based on metal salts such as aluminium, titanium and tin halides are widely used in several synthetic methods [17]. Conversely, the use of catalysts based on metal complexes as such rare earth metal triflates and metallocene compounds has been also developed [18]. Recently, the use of both types of catalysts, i.e.…”

Section: Environmental Benefits Of Use Of Lewis Acid Catalysts For Bimentioning

confidence: 99%

Esterification of Oleic Acid for Biodiesel Production Catalyzed by SnCl2: A Kinetic Investigation

2008

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Abstract:The production of biodiesel from low-cost raw materials which generally contain high amounts of free fatty acids (FFAs) is a valuable alternative that would make their production costs more competitive than petroleum-derived fuel. Currently, the production of biodiesel from this kind of raw materials comprises a two-stage process, which requires an initial acid-catalyzed esterification of the FFA, followed by a basecatalyzed transesterification of the triglycerides. Commonly, the acid H 2 SO 4 is the catalyst on the first step of this process. It must be said, however, that major drawbacks such as substantial reactor corrosion and the great generation of wastes, including the salts formed due to neutralization of the mineral acid, are negative and virtually unsurmountable aspects of this protocol. In this paper, tin(II) chloride dihydrate (SnCl 2 ·2H 2 O), an inexpensive Lewis acid, was evaluated as catalyst on the ethanolysis of oleic acid, which is the major component of several fat and vegetable oils feedstocks. Tin chloride efficiently promoted the conversion of oleic acid into ethyl oleate in ethanol solution and in soybean oil samples, under mild reaction conditions. The SnCl 2 catalyst was shown to be as active as the mineral acid H 2 SO 4 . Its use has relevant advantages in comparison to mineral acids catalysts, such as less corrosion of the reactors and as well as avoiding the unnecessary neutralization of products. Herein, the effect of the principal parameters of reaction on the yield and rate of ethyl oleate production has been investigated. Kinetic measurements revealed that the esterification of oleic acid catalyzed by SnCl 2 ·2H 2 O is first-order in relation to both FFAs and catalyst concentration. Experimentally, it was verified that the energy of activation of the esterification reaction of oleic acid catalyzed by SnCl 2 was very close those reported for H 2 SO 4 . OPEN ACCESSEnergies 2008, 1 80

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Section: Environmental Benefits Of Use Of Lewis Acid Catalysts For Bimentioning

confidence: 99%

Esterification of Oleic Acid for Biodiesel Production Catalyzed by SnCl2: A Kinetic Investigation

2008

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“…The resulting mixture was kneaded thoroughly and aged for 2 hrs at 23 °C, followed by drying at 23 °C for 12 hrs. After drying, 4.5 mL of a sodium hydroxide solution (2.0 M) was added to the dried solid according to the method used in reference [22] . The mixture was again kneaded and thereafter aged for 2 hrs at 23 °C and dried at 23 °C for 12 hrs.…”

Section: Metal Oxide Catalyst Preparationmentioning

confidence: 99%

“…Several studies reported that Mg-Al hydrotalcites [4,5,21] and metal oxides (Al2O3-SnO, Al2O3-ZnO) [22] were active for the transesterification of vegetable oils with methanol at a relatively low reaction temperature. Although sodium hydroxide or sodium carbonate compounds were used in these catalyst preparations, the catalytic activity and deactivation behavior of the metal oxide catalysts were reported as originating from metal oxides (Al2O3-SnO, Al2O3-ZnO) or Mg-Al hydrotalcites sites [4,5,21,22]. As a result, there are conflicting reports of the catalytic activity of the metal oxides catalysts at low temperature for transesterification of vegetable oil and methanol.…”

Section: Introductionmentioning

confidence: 99%

The effect of sodium on the catalytic activity of ZnO–Al2O3/ZSM-5 and SnO–Al2O3/ZSM-5 for the transesterification of vegetable oil with methanol

Kim

Yan

Salley

et al. 2009

Catalysis Communications

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In order to elucidate the effect of sodium on the activity of ZSM-5 supported metal oxides catalysts (ZnO-Al2O3/ZSM-5 and SnO-Al2O3/ZSM-5) for the transesterification of soybean oil with methanol, ZSM-5 supported metal oxides were prepared with and without sodium hydroxide by impregnation. The metal compositions of the ZSM-5 supported metal oxide catalysts and the metal concentrations dissolved from the catalysts to the methylester phase were measured by SEM-EDS and inductive coupled plasma spectroscopy, respectively. The catalytic activity of ZnO-Al2O3/ZSM-5 and SnO-Al2O3/ZSM-5 containing sodium did not originate from surface metal oxides sites, but from surface sodium sites or dissolved sodium leached from the catalyst surface.

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“…Transesterification is a widespread process used for obtaining biodiesel and involves the catalyzed reaction of triacylglycerides (TAGs) and short-chain mono-alcohols (such as methanol and ethanol) to produce fatty acid methyl or ethyl esters (biodiesel). 3,4 This process was the chosen technology by several biofuel programs, such as the National Program of Production and Use of Biodiesel (PNPB) in Brazil. 2 Biodiesel is considered the best fuel substitute for diesel due to its physical properties, which are close to those of fossil diesel.…”

Section: Introductionmentioning

confidence: 99%

Chromatographic analyses of fatty acid methyl esters by HPLC-UV and GC-FID

Carvalho¹,

Mendonça

Pinho³

et al. 2012

J. Braz. Chem. Soc.

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Um método analítico por cromatografia líquida de alto rendimento com detecção ultravioleta (HPLC-UV) (método A) foi utilizado na determinação simultânea dos valores totais de triacilglicerídeos, diacilglicerídeos, monoacilglicerídeos e ésteres metílicos de ácidos graxos na alcólise de diferentes óleos (algodão, canola, girassol, milho e soja). As análises foram realizadas a 40 °C por 20 min usando gradiente de metanol (MeOH) e 2-propanol-hexano 5:4 (v/v) (PrHex): 100% de MeOH em 0 min, 50% de MeOH e 50% de PrHex em 10 min mantido com eluição isocrática por 10 min. Outro método por HPLC-UV (método B) com eluição isocrática de acetonitrila por 34 min foi utilizado na determinação da composição de ácidos graxos de óleos analisando seus derivados de éster metílico. Os conteúdos foram analisados com satisfatória repetibilidade (desvio padrão relativo, RSD < 3%), linearidade (r 2 > 0,99) e sensibilidade (limite de quantificação). O método B foi comparado com o método oficial cromatográfico gasoso com detecção através de ionização por chama (GC-FID) da American Oil Chemists' Society (AOCS) na determinação de ésteres metílicos de ácidos graxos (FAME) em amostras reais de biodiesel.An analytical method using high performance liquid chromatography with UV detection (HPLC-UV) (method A) was used for simultaneous determination of total amounts of triacylglycerides, diacylglycerides, monoacylglycerides and fatty acid methyl esters in alcoholysis of different oil (cotton, canola, sunflower, corn and soybean) samples. Analyses were carried out at 40 °C for 20 min using a gradient of methanol (MeOH) and 2-propanol-hexane 5:4 (v/v) (PrHex): 100% of MeOH in 0 min, 50% of MeOH and 50% of PrHex in 10 min maintained with isocratic elution for 10 min. Another HPLC-UV method (method B) with acetonitrile isocratic elution for 34 min was used to determine the fatty acid composition of oils analyzing their methyl ester derivatives. Contents were determined with satisfactory repeatability (relative standard deviation, RSD < 3%), linearity (r 2 > 0.99) and sensitivity (limit of quantification). Method B was compared with an official gas chromatographic method with flame ionization detection (GC-FID) from American Oil Chemists' Society (AOCS) in the determination of fatty acid methyl esters (FAME) in biodiesel real samples.Keywords: biodiesel, triacylglycerides, gas chromatography, liquid chromatography, methyl ester IntroductionThe direct use of fats and oils (mainly composed by triacylglycerides) in diesel engines is problematic and can lead to many problems, such as carbon deposit due to its poor atomization, high viscosity and thickening of lubricating oil as a consequence of its low volatility. 1,2 There are many possible solutions to address the viscosity problem, which are dilution with diesel fuel, microemulsions with short chain alcohols and pyrolysis or transesterification of triacylglycerides. Transesterification is a widespread process used for obtaining biodiesel and involves the catalyzed reaction of triacylglycerides (TAGs) a...

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New heterogeneous metal-oxides based catalyst for vegetable oil trans-esterification

Cited by 92 publications

References 20 publications

Esterification of Oleic Acid for Biodiesel Production Catalyzed by SnCl2: A Kinetic Investigation

Esterification of Oleic Acid for Biodiesel Production Catalyzed by SnCl2: A Kinetic Investigation

The effect of sodium on the catalytic activity of ZnO–Al2O3/ZSM-5 and SnO–Al2O3/ZSM-5 for the transesterification of vegetable oil with methanol

Chromatographic analyses of fatty acid methyl esters by HPLC-UV and GC-FID

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