scholarly journals Kinetic and Transesterification Properties of Lipase from Sprouted Melon (Cucumeropsis manni) Seeds

2021 ◽  
Vol 25 (7) ◽  
pp. 1341-1346
Author(s):  
P.O. Osemwenkhae ◽  
P.O. Uadia
Keyword(s):  
Methyl Esters ◽  
Acetone Powder ◽  
Kinetic Properties ◽  
Alkyl Esters ◽  
Transportation Fuel ◽  
Reaction Conditions ◽  
Apparent Decrease ◽  
Substrate Ratio ◽  
Melon Seeds ◽  
Active Lipase

Crude lipase (acetone powder) was extracted from freshly sprouted melon seeds (Cucumeropsis manni). The activity, kinetic properties (effect of time, pH, and enzyme and substrate concentration, respectively) as well as the ability of the crude lipase to catalyze the production of methyl esters (biodiesel) were examined. The enzyme activity was determined using n-hexane as the solvent (1:2 v/w solvent: substrate ratio) and the transesterification product was analyzed by HPLC. A linear relationship was observed between reaction time and rate of lipolysis with the optimal activity at 2hr of incubation. Furthermore, the lipase was optimally active at acid pH 5 and lipolysis was achieved optimally when the amount of enzyme was 2.0g. Rate of lipolysis was observed to increase linearly at concentrations up to 5.0g of substrate above which a drop in the rate, with no apparent decrease in activity, was observed. The Km (6.25g) and Vmax (13.33%FFA/hr) were also determined. Analysis of the transesterification product yielded 0.61% alkyl ester, 0.81 %FFA, 93.17% TAG, 4.15% 1, 3-DAG and 1.26% 1, 2-DAG while transesterification efficiency was determined to be at 0.588%. Biodiesel (alkyl esters) prepared with the crude lipase was had a density of 0.872 g/mL while its cloud and pour points were 22°C and 12°C, respectively. The results from this research showed that an active lipase was isolated from sprouted melon seeds. However, the fuel properties of the biodiesel produced did not meet international transportation fuel standards. In order to be used industrially, better reaction conditions need to be established for the lipase.

scholarly journals USE OF CERAMIC MATERIAL (CEMENT CLINKER) FOR THE PRODUCTION OF BIODIESEL

2013 ◽  
Vol 22 ◽  
pp. 71-78
Author(s):  
SUNNY SONI ◽  
MADHU AGARWAL
Keyword(s):  
Soybean Oil ◽  
Edible Oils ◽  
Methyl Esters ◽  
Catalytic Performance ◽  
Cement Clinker ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Rural Economic Development ◽  
Additional Demand ◽  
Biodiesel Fuels

Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.

scholarly journals Evaluation of dolomite as catalyst in the transesterification reaction using palm oil (RBD)

DYNA ◽  
2019 ◽  
Vol 86 (209) ◽  
pp. 180-187
Author(s):  
Stephanie Alexa Ñústez Castaño ◽  
Duvan Oswaldo Villamizar Castro ◽  
Edgar Mauricio Vargas Solano
Keyword(s):  
Palm Oil ◽  
Batch Reactor ◽  
Methyl Esters ◽  
Average Pore Size ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Average Pore ◽  
X Ray ◽  
Rbd Palm Oil ◽  
Methyl Ester Content

In this study, the catalytic activity of dolomite was evaluated for the transesterification of Colombian RBD palm oil with methanol, carried out in a batch reactor at 333,15K and 600rpm. The activated dolomites (calcined at 1073.15K for 2h) were characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), Hammett indicators method, and quantification of the surface area, average pore size and average pore volume BET. The influence of reaction variables such as catalyst amount (%wt /wt) and methanol / palm oil molar ratio (mole/mole) was investigated. Under the suitable reaction conditions, the amount of calcined dolomite equal to 4% (wt /wt) based on the weight of oil, the methanol-oil molar ratio equal to 9:1, and the reaction time = 1h, the methyl ester content of 82.67% of fatty acid methyl esters (FAME) can be achieved.

scholarly journals High-Quality Biodiesel Production from Buriti (Mauritia flexuosa) Oil Soapstock

Molecules ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 94 ◽  
Author(s):  
Samantha Pantoja ◽  
Vanessa Mescouto ◽  
Carlos Costa ◽  
José Zamian ◽  
Geraldo Rocha Filho ◽  
...  
Keyword(s):  
Reaction Time ◽  
Methyl Esters ◽  
Natural Antioxidants ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Palm Tree ◽  
Reaction Conditions ◽  
Mauritia Flexuosa ◽  
Buriti Oil ◽  
Brazilian Standard

The buriti palm (Mauritia flexuosa) is a palm tree widely distributed throughout tropical South America. The oil extracted from the fruits of this palm tree is rich in natural antioxidants. The by-products obtained from the buriti palm have social and economic importance as well, hence the interest in adding value to the residue left from refining this oil to obtain biofuel. The process of methyl esters production from the buriti oil soapstock was optimized considering acidulation and esterification. The effect of the molar ratio of sulfuric acid (H2SO4) to soapstock in the range from 0.6 to 1.0 and the reaction time (30–90 min) were analyzed. The best conditions for acidulation were molar ratio 0.8 and reaction time of 60 min. Next, the esterification of the fatty acids obtained was performed using methanol and H2SO4 as catalyst. The effects of the molar ratio (9:1–27:1), percentage of catalyst (2–6%) and reaction time (1–14 h) were investigated. The best reaction conditions were: 18:1 molar ratio, 4% catalyst and 14 h reaction time, which resulted in a yield of 92% and a conversion of 99.9%. All the key biodiesel physicochemical characterizations were within the parameters established by the Brazilian standard. The biodiesel obtained presented high ester content (96.6%) and oxidative stability (16.1 h).

A practical chlorination of tert-butyl esters with PCl3 generating acid chlorides

2020 ◽  
Vol 44 (5-6) ◽  
pp. 301-304
Author(s):  
Xiaofang Wu ◽  
Lei Zhou ◽  
Ruoqi Yang ◽  
Fengzhe Guo ◽  
Zi-Long Tang ◽  
...  
Keyword(s):  
Aromatic Acid ◽  
Aliphatic Acid ◽  
Acid Chlorides ◽  
Alkyl Esters ◽  
Reaction Conditions ◽  
Simple Reaction ◽  
Tert Butyl ◽  
Butyl Esters ◽  
Plausible Mechanism ◽  
First Time

For the first time, using PCl3, a range of tert-butyl esters is chlorinated successfully, allowing access of both aromatic acid chlorides and aliphatic acid chlorides in good yields. The method features simple reaction conditions and wide substrate scope. Various tert-butyl esters including aryl esters, alkenyl esters, and alkyl esters were tolerated well in the reaction. A plausible mechanism is proposed.

scholarly journals Unusual Regularity in GC Retention of Simple Amino Acid Derivatives

2019 ◽  
Vol 6 (1) ◽  
pp. 3-14 ◽  
Author(s):  
Igor G. Zenkevich ◽  
Nino G. Todua ◽  
Anzor I. Mikaia
Keyword(s):  
Gas Chromatography ◽  
Retention Index ◽  
Methyl Esters ◽  
Elution Order ◽  
Alkyl Esters ◽  
Methyl Group ◽  
The Difference ◽  
Direct Use ◽  
Derivatives Of

Background: Application of simple regularities and general principles along with direct use of reference gas chromatography retention index data for reliable structure determination of compounds can be enhanced by determination of new regularities that are specific to certain structural elements. Objective: Revelation and interpretation of an anomaly in the elution order of alkyl esters of alkoxycarbonyl derivatives of glycine and alanine on standard and semi-standard non-polar phases. Method: Preliminary derivatization of amino acids to alkyl esters of N-alkoxycarbonyl analogs and interpretation of their gas chromatographic characteristics. Results: Alkyl esters of N-alkoxycarbonyl derivatives of alanine (Alkyl = C2H5, n- and iso-C3H7) elute prior to the same derivatives of glycine, despite the presence of an additional methyl group at C(2) in the molecule. Elution order is reversed for methyl esters of N-methoxycarbonyl derivatives. Conclusion: It is established that the peculiar behavior of alkyl esters of N-alkoxycarbonyl derivatives of glycine and alanine agrees with the concepts of gas chromatography and the known retention index regularities of organic compounds. A decrease of retention index values is a result of an introduction of an additional methyl group to a carbon atom connected to two polar fragments in a molecule like CH2XY. The dependence of the difference of retention index values for homologs of the types of CH3-CHXY and CH2XY vs. the total mass of fragments (X + Y) is similar to those for other sub-groups of analytes.

Gas Chromatographic Determination of 2,4-D and 2,4,5-T and Their Derivatives in Commercial Formulations

1965 ◽  
Vol 48 (2) ◽  
pp. 327-333
Author(s):  
Patricia L Pursley ◽  
E D Schall
Keyword(s):  
Gas Chromatography ◽  
Chromatographic Analysis ◽  
Methyl Esters ◽  
Chromatographic Determination ◽  
Dichlorophenoxyacetic Acid ◽  
Alkyl Esters ◽  
Boron Trichloride ◽  
Acid Gas ◽  
Gas Chromatographic Analysis

Abstract A solution of boron trichloride in methanol was employed for the complete transcsterification of 2,4-D and 2,4,5-T esters to the corresponding methyl esters. Gas chromatographic analysis of the methyl esters permitted mixtures of 2,4-D and 2,4,5-T esters in commercial formidations to be analyzed both qualitatively and quantitatively with no sample cleanup. The method is highly specific and detected the presence of other contaminating isomers of dichlorophenoxyacetic acid. Gas chromatography was also used to qualitatively analyze mixtures of various alkyl esters of 2,4-D.

The use of sulfated tin oxide as solid superacid catalyst for heterogeneous transesterification of Jatropha curcas oil

2010 ◽  
Vol 64 (6) ◽  
Author(s):  
Gerald Kafuku ◽  
Keat Lee ◽  
Makame Mbarawa
Keyword(s):  
Tin Oxide ◽  
Jatropha Curcas ◽  
Methyl Esters ◽  
Solid Catalyst ◽  
Reaction Conditions ◽  
Jatropha Curcas Oil ◽  
Biodiesel Standards ◽  
Superacid Catalyst ◽  
Astm D6751 ◽  
Central Composite

AbstractThis work presents the use of sulfated tin oxide enhanced with SiO2 (SO42−/SnO2-SiO2) as a superacid solid catalyst to produce methyl esters from Jatropha curcas oil. The study was conducted using the design of experiment (DoE), specifically a response surface methodology based on a threevariable central composite design (CCD) with α = 2. The reaction parameters in the parametric study were: reaction temperature (60°C to 180°C), reaction period (1 h to 3 h), and methanol to oil mole ratio (1: 6 to 1: 24). Production of the esters was conducted using an autoclave nitrogen pressurized reactor equipped with a thermocouple and a magnetic stirrer. The maximum methyl esters yield of 97 mass % was obtained at the reaction conditions: temperature of 180°C, reaction period of 2 h, and methanol to oil mole ratio of 1: 15. The catalyst amount and agitation speed were fixed to 3 mass % and 350–360 min−1, respectively. Properties of the methyl esters obtained fell within the recommended biodiesel standards such as ASTM D6751 (ASTM, 2003).

scholarly journals Rapid NIR determination of alkyl esters in virgin olive oil

2017 ◽  
Vol 68 (2) ◽  
pp. 195 ◽  
Author(s):  
J. A. Cayuela
Keyword(s):  
Fatty Acid ◽  
Olive Oil ◽  
Predictive Models ◽  
Near Infrared ◽  
Methyl Esters ◽  
External Validation ◽  
Virgin Olive Oil ◽  
Ethyl Esters ◽  
The European Union ◽  
Alkyl Esters

The regulation of The European Union for olive oil and olive pomace established the limit of 35 mg·kg-1 for fatty acids ethyl ester contents in extra virgin olive oils, from grinding seasons after 2016. In this work, predictive models have been established for measuring fatty acid ethyl and methyl esters and to measure the total fatty acid alkyl esters based on near infrared spectroscopy (NIRS), and used successfully for this purpose. The correlation coefficients from the external validation exercises carried out with these predictive models ranged from 0.84 to 0.91. Different classification tests using the same models for the thresholds 35 mg·kg-1 for fatty acid ethyl esters and 75 mg·kg-1 for fatty acid alkyl esters provided success percentages from 75.0% to 95.2%.

Sign in / Sign up

Export Citation Format

Share Document