Chemically modified Jatropha curcas oil for biolubricant applications

Jatropha curcas oil is one of interesting renewable resources for preparation of biolubricants. However, direct application of this oil as a biolubricant is restricted due to its low oxidative stability. This drawback can be overcome by molecule structural redesign through a chemical modification process at its unsaturated functional groups. Jatropha curcas oil was modified via epoxidation, ring opening and esterification processes. Its conversion to the epoxidized oil was performed by using in situ performic acid as a catalyst, then reaction with oleic acid in the presence of p-toluenesulfonic acid as a catalyst in the ring opening process. The final esterification process with oleic acid was catalyzed by sulfuric acid. Molecular structures of the modified oil were determined by measurements of the oxirane oxygen content and by Fourier-transform infrared (FTIR), proton and carbon nuclear magnetic resonance (1H NMR and 13C NMR) spectroscopy analyses. The results showed that the oxidative stability, viscosity, flash point and pour point of the final product were significantly improved. In specific, the ring opening and esterification processes inducing branching and bending in the final oil molecular structure have resulted in the improved viscosity index of 135, the pour point of -29?C and the increased flash point of 250?C.

Mutation of an atypical oxirane oxyanion hole improves regioselectivity of the α/β-fold epoxide hydrolase Alp1U.

Epoxide hydrolases (EHs) have been characterized and engineered as biocatalysts that convert epoxides to valuable chiral vicinal diol precursors of drugs and bioactive compounds. Nonetheless, the regioselectivity control of the epoxide ring opening by EHs remains challenging. Alp1U is an α/β-fold EH that exhibits poor regioselectivity in the epoxide hydrolysis of fluostatin C (1), and produces a pair of stereoisomers. Herein, we established the absolute configuration of the two stereoisomeric products and determined the crystal structure of Alp1U. A W186/W187/Y247 oxirane oxygen hole was identified in Alp1U that replaced the canonical Tyr/Tyr pair in α/β-EHs. Mutation of residues in the atypical oxirane oxygen hole of Alp1U improved the regioselectivity for epoxide hydrolysis on 1. The single site Y247F mutation led to highly regioselective (98%) attack at C-3 of 1, while the double mutation W187F/Y247F resulted in regioselective (94%) nucleophilic attack at C-2. Furthermore, single crystal X-ray structures of the two regioselective Alp1U variants in complex with 1 were determined. These findings allowed insights into the reaction details of Alp1U, and provided a new approach for engineering regioselective epoxide hydrolases.

Chemical Modification of Camelina Oil based Unsaturated Fatty Acid for Renewable Biolubricant Base Stock

A green and eco-friendly method for preparation of oleochemicals from Camelina oil was developed for possible application for bio-lubricant basestocks, The steps involved are consisting of epoxidation of Camelina oil based fatty acid followed by further branching with wide range of alcohol such as 2-propanol, n-butanol, isoamyl alcohol and 2-ethylhexanol. These products were evaluated with physico-chemical properties such as acid value, oxirane oxygen content (OOC), hydroxyl value, low temperature properties, viscosity at 40 and 100 °C, viscosity index and characterized by FTIR, 1H NMR. The appearance of peak at 824 cm–1 in the FTIR spectra was due to the formation of epoxy group and broad peak appeared at 3500-3300 cm–1 is for hydrogen bonded O-H stretching vibration of hydroxy group. The 1H NMR spectra showed a signal at 2.9-3.2 ppm region indicated CH-proton attached to the oxygen atom of the both epoxy group for epoxidized product, peaks for newly formed secondary alcohols emerged at 4.25-3.35 in alkoxy derivatives. The Camelina based synthetic product may find application in biolubricants base stock.

Optimization of the Ring Opening of Epoxidized Palm Oil using D-Optimal Design

In the presence of a catalyst, p-toluenesulfonic acid (PTSA), the ring of epoxidized palm oil (EPO) was opened using oleic acid (OA). The optimization effects of different process variables including the mol ratio of EPO/OA, reaction temperature, PTSA percentage and reaction time was performed by response surface methodology (RSM). To assess the effects of process variables and interactions among them, a D-optimal design was used as an RSM tool to acquire the maximum response value. The following are the optimum conditions achieved at the reaction time of 4.73 h in the RSM study: 1.02% PTSA, 3 EPO/OA mol ratio and 119.14 ºC reaction temperature. These conditions resulted in 84% yield, 0.041% oxirane oxygen content (OOC), 59.4 mg/g iodine value (IV), and118.7 mg/g hydroxyl value (HV). The results are in a excellent agreement with the values predicted using a regression model.

In-Situ Synthesis and Characterization of Biodegradable Estolides via Epoxidation from Canola Biodiesel

Research on the formulation of estolides from plant seed oils has attracted substantial attention due to their favorable low-temperature properties and environmentally friendly nature. The present research investigates the formulation of canola biodiesel derived estolides for low-temperature applications. The dual-step research method includes ring opening of epoxidized canola biodiesel in the presence of oleic acid, followed by esterification with oleic acid to produce estolides using a mesoporous aluminosilicates possessing Modernite Framework Inverted (MFI) type pentasil structure as a heterogeneous acidic catalyst. Prepared catalyst was characterized to measure the properties essential for the effective catalysis. The catalyst demonstrated promising activity for the estolides formation, >95% conversion was achieved at 110 °C for 6 h using 15 wt % of catalyst loading. 1H NMR technique and oxirane oxygen titrimetric analysis were employed to determine product purity. Physicochemical properties of the reaction products were determined by standard methods and characterization results revealed that the formulated estolides had improved low-temperature, lubricity and rheological properties, and thermo-oxidative stability. Also, biodegradability of the estolides was found to be 92% within 28 days as per the bio-kinetic model. Wear scar diameter of 106 µm was noticed for 10% of alkoxide blend with standard diesel fuel. Overall, outcomes of the physicochemical characterization data indicated that the prepared estolides can act as possible alternative bio-lubricant basestock for various low-temperature applications.

Technological Parameters of Epoxidation of Sesame Oil with Performic Acid

The course of epoxidation of sesame oil (SO) with performic acid formed „in situ” by the reaction of 30 wt% hydrogen peroxide and formic acid in the presence of sulfuric acid(VI) as a catalyst was studied. The most advantageous of the technological independent parameters of epoxidation are as follows: temperature 80°C, H2O2/ C=C 3.5:1, HCOOH/C=C 0.8:1, amount of catalyst as H2SO4/(H2O2+HCOOH) 1 wt%, stirring speed at least 700 rpm, reaction time 6 h. The iodine number (IN), epoxy number (EN), a relative conversion to oxirane (RCO) and oxirane oxygen content (EOe) were determined every hour during the reaction. Under optimal conditions the sesame oil conversion amounted to 90.7%, the selectivity of transformation to epoxidized sesame oil was equal to 93.2%, EN = 0.34 mol/100 g, IN = 0.04 mol/100 g oil (10.2 g/100 g oil), a relative conversion to oxirane RCO = 84.6%, and oxirane oxygen content of EOe = 5.5%.

Lipase-catalyzed transesterification of epoxidized soybean oil to prepare epoxy methyl esters

Epoxidized soybean oil methyl esters could be efficiently prepared with the transesterification of epoxidized soybean oil (ESBO) with a lower dosage of methanol using lipase Novozym 435 as catalyst. The optimum parameters were as follows: the molar ratio of 5:1 (methanol to ESBO), 5% Novozym 435 as catalyst, at 45 °C for 14 h, with a stirring speed of 600rpm, under which the epoxidized soybean oil methyl esters (ESBOME) could be obtained at a 95.7% yield. During the enzymatic transesterification process, the oxirane oxygen values were kept unchangeable, which indicated that excellent functional group tolerance could be achieved under such mild reaction conditions. In addition, the recyclability of the immobilized enzyme Novozym 435 in this transesterification process was examined and the results showed that the biocatalyst could be reused ten times without losing any reaction activity or selectivity. And the final products of ESBOME were also identified by IR and NMR analysis. The kinetic data obtained followed the Ping-Pong Bi mechanism model (Vmax = 6.132 mol·L-1min-1, Km,S = 0,0001 mol·L-1, Km, A = 796.148 mol·L-1, Ki, A = 0,0004 mol·L-1) with competitive inhibition by methanol.

Comparative Analysis on the Epoxidation of Soybean Oil using Formic and Acetic Acids

The objective of this study was to make a comparative analysis of the effect of formic and acetic acids as oxygen carriers on the epoxidation of soybean oil used with hydrogen peroxide as the oxygen donor. Comparative analysis between the use of formic acid (FA) and acetic acid (AA) was studied to obtain the most effective oxygen carrier that yielded high oxirane oxygen contents (OOC). The epoxidation reaction was carried out using a stoichiometric ratio of 1:0.5:1, 1:0.5:0.5, and 1:0.5:2 of soybean oil: formic/acetic acid: hydrogen peroxide. The synthesis was performed at three reaction times (2, 4 and 6 h) at a constant temperature of 50°C. Samples prepared using FA and AA were characterized using ASTM D1652-11 and confirmed by Fourier transform infrared (FTIR) spectroscopy. The result of this study proved FA to be an effective oxygen carrier compared to that of AA based on the high OOC and percent yield achieved. The optimum epoxidized soybean oil (ESO) sample using FA was obtained at a reaction time of 6 h using 2 moles of H2O2, yielding an OOC of 7.45 at a relative conversion to oxirane of 98%. Samples of FA were further characterized to prove the optimum parameters that gave the highest OOC using rheology and gel permeation chromatography (GPC). Rheology data revealed an increase in the viscosity that implied an increase in the degree of epoxidation. GPC indicated an increase in the molecular weight at low reaction times, then a decrease resulting in a change in the structure of the triglyceride and consequently an increase in the extent of epoxidation.

The Synthesis of Bio-Polyol from Epoxidized Soybean Oil

Hydroxyl and oxirane functionality were calculated from molecular weight and hydroxyl or oxirane-oxygen content of polyol. The effect of reaction parameters like the amount of reagents, catalyst, temperature and time on a polyol synthesis was studied through the hydroxyl and oxirane functionality of product. Moreover, the impact of the parameters on the selectivity of catalyst was determined by comparing a polyol yield to an epoxide ring opening yield. When the hydroxylation reaction was carried out with ESO:H2O molar ratio of 1:15; in 8 wt.% of H2SO4; at temperature of 70oC and in 5 hours, the polyol yield of reaction was 70.32% and the hydroxyl functionality of polyol reached to 5.63

PENGARUH KONSENTRASI KATALIS DAN WAKTU REAKSI PADA PEMBUATAN EPOKSI MINYAK GORENG BEKAS

Epoxy is produced from an epoxidation of vegetable oil or natural oil with au nsaturated bond. Epoxy can be applied as a stabilizer, plasticizers in polyvinyl chloride (PVC) and can be used as an antioxidant in natural rubber processing, as a surfactant, anti-corrosive additive agent in lubricants and pesticide raw materials. The purpose of this research was to evaluate epoxy production from waste cooking oil. In this research, waste cooking oil was reacted with hexane as solvent, sulfuric acid as catalyst, glacial acetic acid and hydrogen peroxide. The catalyst concentration was varied from 1.5%, 2.1%, 2.5%, 3.1% and 3.5% and the epoxidation time was varied from 60, 120, 180, 240 and 300 min. The results showed that highest epoxy yield was achieved at reaction time of 300 min and 1.5% catalyst. At that condition, the iod number was 0,96 g I2/100 g WCO, oxirane oxygen content was 1.872 and oxirane oxygen conversion was 62.259%.