Hydrogenation Of Palm Oil Research Articles

Analysis of palm oil hydrodeoxygenation pathway selectivity based on oxygen quantification

Hydrogenation of palm oil over commercial NiMo/γ-Al2O3 catalysts and the effect of operating conditions were investigated in an autoclave with a continuous H2 flow mode. Methanation as the side reactions were taken into account in the reaction path selectivity for the first time. Three competing reaction pathways of hydrodecarboxylation, hydrocarbonation, and direct hydrodeoxygenation were clearly distinguished by quantifying the oxygen in the aqueous, organic, and gas phases. The results corroborated that the temperature and hydrogen supply were crucial to oxygen removal and the selectivity of the HDO pathways. Methane is the predominant gas product rather than propane during triglyceride deoxygenation, in which 87–100% of the methane production comes from the glycerol skeleton of the triglyceride and the rest comes from the CO methanation. Lower temperature favored the direct HDO route, while the selectivity of the HDCO and HDCO2 reactions preferred a higher temperature. HDO dominated the hydrodeoxygenation process under all H2 supply conditions, followed by the HDCO2 pathway and the HDCO reaction. This study brings the understanding of the vegetable oil triglyceride hydrodeoxygenation process to the molecular level and can potentially guide the optimization of process conditions.

Dielectric barrier discharge plasma for catalytic-free palm oil hydrogenation using glycerol as hydrogen donor for further production of hydrogenated fatty acid methyl ester (H-FAME)

Catalytic-free parallel-plate-type dielectric barrier discharge (DBD) plasma was successfully employed to hydrogenate palm oil using glycerol as hydrogen donor in place of hydrogen gas for further production of hydrogenated fatty acid methyl ester (H-FAME) with enhanced oxidation stability. Most suitable reaction condition was 1:5 oil to glycerol molar ratio, 1 cm discharge gap size, 0.5 L/min He gas flow rate, atmospheric pressure, ambient temperature (rising to about 100 °C due to plasma heating), and 500 rpm stirring rate for 2 h at 130 W input power. Findings revealed that plasma could extract hydrogen radicals from glycerol, and they successfully reacted with CC bonds. Hydrogenated palm oil was subsequently converted into hydrogenated FAME (H-FAME) via conventional base-catalyzed transesterification. Higher saturation degree of H-FAME compared to FAME produced directly from palm oil was indicated by reduction of iodine value to 52.2 from 59.2. Oxidation stability of H-FAME was significantly enhanced from 17.7 to 23.1 h while cloud point slightly changed from 14.0 to 14.8 °C. Plasma reactive species generated during reaction and possible mechanisms of glycerol decomposition and plasma hydrogenation were presented. Developed catalytic-free plasma hydrogenation process is highly environmentally friendly and presents a way to add more value to waste glycerol and provide other potential hydrogen sources.

Neuronal Nitric Oxide Synthase Regulates Depression-like Behaviors in Shortening-Induced Obese Mice.

Shortening is mainly derived from the partial hydrogenation of palm oil and widely used in fast food. Food processed with shortening contains high levels of industrial trans fatty acids. Studies have shown that there is a correlation between industrial trans fatty acids, obesity, and depression. However, the regulatory effect of neuronal nitric oxide synthase (nNOS) on depression in obese patients is still unknown. The purpose of this study was to explore mood changes in obese mice fed a high shortening diet, and to determine the regulatory effect of nNOS on depressive-like behaviors in obese mice. We used a high shortening diet-induced obesity mouse model to systematically assess the metabolic response, behavioral changes, prefrontal and hippocampal nNOS protein levels, and the effect of nNOS inhibitors (7-nitroindole) on depression-like behavior in obese mice. Interestingly, obese mice on a 9-week high-shortening diet developed short-term spatial working memory impairment and anxiety-like behavior, and obesity may be a risk factor for cognitive impairment and mood disorders. In animals fed a high shortening diet for 12 weeks, obese mice developed depression-like behavior and had significantly elevated levels of nNOS protein expression in the hippocampus and prefrontal lobe. Administration of the nNOS inhibitor 7-nitroindole could improve depression-like behaviors in obese mice, further suggesting that inhibition of nNOS is helpful for depression associated with obesity.

Production of low trans-fat margarine by partial hydrogenation of palm oil using nature-friendly and catalyst-free microwave plasma technique

A 2.45 GHz microwave (MW) plasma furnished with a negative high voltage has been successfully utilized for partial hydrogenation of palm olein to produce low trans-fat margarine at low temperature and low pressure in the absence of a catalyst. The effects of various parameters: H2 flow rate, microwave power, reaction temperature, negative high voltage and reaction duration on the iodine value (IV) and culinary characteristics of the hydrogenated oil were investigated. The results showed the optimal parameters of 4 L-min−1 H2 flow rate, 600 W MW power, 32 °C (due to self-heating of the plasma), 60 kV negative high voltage and 4 h reaction duration, reducing the iodine value from 57.7 to 32.5 with good texture and slip melting point (SMP). The trans-fatty acid was detected by GC–MS to be 4.23%, being lower than conventional catalytic hydrogenation. This catalyst-free MW plasma hydrogenation of vegetable oil under benign conditions is a green alternative for the production of low trans-fat margarine.

PSII-15 Hydrogenation of palm kernel oil, palm oil, and soybean oil on energy and lipid digestibility, and performance when fed to 20 to 40 kg pigs

Abstract The objective of this study was to evaluate the effect of feeding hydrogenated palm kernel oil (PKO), palm oil (PO), or soybean oil (SO) relative to unhydrogenated PKO, PO, and SO on apparent total tract digestibility (ATTD) of gross energy (GE) and ether extract (EE), and on pig performance, in to 20 to 40 kg pigs. One hundred and fifty-four pigs (39.5 ± 3.6 kg BW) were randomly assigned to one of 9 diets composed of a basal diet, or test diets containing 94% of the basal diet and 6% added lipid. Lipids consisted of either unhydrogenated or hydrogenated PKO, PO, or SO in a factorial arrangement. The basal diet contained titanium dioxide as an inert maker and was used to determine the ATTD of GE or EE of each lipid using the difference method. There were 2 pigs per pen with pigs ad libitum fed for 25 d to measure growth performance. On d 23 and 24, a fresh fecal sample was obtained from each pen to measure ATTD of GE and EE. There was an interaction between lipid source and hydrogenation for ATTD of GE and EE of the lipid (P ≤ 0.01), where hydrogenation of PKO had no effect on ATTD of GE or EE of the lipid, while hydrogenation of PO and SO resulted in a reduction in the ATTD of GE and EE compared to their unhydrogenated counterparts. There was also an interaction between lipid source and hydrogenation on GF (P ≤ 0.01) where hydrogenation of PKO had no effect on GF while hydrogenation of PO and SO resulted in a reduction in GF compared to their unhydrogenated counterparts. The data show that hydrogenation of PKO has no impact on ATTD of GE and EE of the lipid, or on GF, but hydrogenation of PO or SO reduce ATTD of GE and EE of the lipid, and GF, due to their fatty acids being longer in carbon chain length.

Non-thermal dielectric barrier discharge plasma hydrogenation for production of margarine with low trans-fatty acid formation

A novel technique for palm oil hydrogenation with very low trans-fatty acid formation using non-thermal dielectric barrier discharge (DBD) plasma with parallel-plate configuration has been successfully demonstrated. This green technique does not require catalyst and is highly environmental-friendly. With 15% H2: 85% He mixed carrier gas concentration ratio and initial 31 °C (rising to 50 °C due to plasma), after 4 h of plasma hydrogenation, iodine value (IV) was reduced from 60.89 to 48.39 and detected trans-fat was 1.44%. This represents trans-fat generation rate of only 0.07% per % decrease in IV, which is about 6.12 times lower than a conventional method relying on high temperature, high pressure and catalyst. About 8 h was required to produce margarine with texture closest to commercial margarines. Acid value (AV) reduced from 0.47 to 0.27%, or 43% reduction, after 12–20 h of treatment, significantly indicating that plasma hydrogenation can also help extend shelf life of oil or margarine. Large portion of DBD plasma hydrogenated palm oil can, thus, be mixed with palm olein and interesterified palm oil to produce margarine with overall trans-fatty acid content no higher than regulatory requirement. Continuous production scheme was presented. This novel plasma hydrogenation technique offers promising possibility for commercial utilization by edible oils industry.

Elimination of 3-MCPD fatty acid esters and glycidyl esters during palm oil hydrogenation and wet fractionation

Palm oil is the vegetable oil refined and modified in the largest amount. In this study, we present the effect of wet fractionation and hydrogenation of RBD palm oil on the removal of 3-MCPD and glycidyl esters. Fractionated palmstearins had significantly decreased contents of 3-MCPD esters (71–74%) and glycidyl esters (21–26%), whereas top olein contained the highest levels of processing-induced contaminants accompanied by polar compounds. Exhaustive hydrogenation conditions caused rapid degradation of 3-MCPD esters (51–70%) in high melting palm oil products. Reduction of glycidyl esters (1–42%) was dependent on the type of nickel catalyst. The effect of iodine value drop on the contaminant degradation was shown to be linear. The combined action of dry-reduced, supported, 22% Ni and Raney nickel catalysts was found to be an optimal. Adsorptive bleaching and deodorization of hydrogenated palm stearin impacted particularly repeated formation of glycidyl esters up to 1.01–1.76 mg/kg, while 3-MCPD esters remained under the input RBD palm oil level. The mechanism of the catalyst action was investigated with glycidyl-d5 palmitate, 3-MCPD-d5-1,2-dipalmitate. They were transformed into non-carcinogenic and non-genotoxic products by hydrogenolysis and deoxygenation reactions.

Effects of Fe on catalytic hydrogenation of palm oil in aqueous solution

Chitosan-stabilised metallic Pd (CTS-Pd) and Pt (CTS-Pt) nanoparticles were synthesised and used for the hydrogenation of palm oil. With the goal of preparing hydrogenated oil with low trans fatty acid (TFA) content under ambient conditions, Fe anion was added as the secondary metallic precursor to synthesise chitosan-stabilised bimetallic Pd–Fe (CTS-Pd–Fe) and Pt–Fe (CTS-Pt–Fe) nanoparticles. The catalytic hydrogenations with newly prepared nanoparticles were performed in aqueous solution under ambient temperature and atmospheric pressure. The addition of Fe was found to improve the catalytic activity and decrease the selectivity for TFA. Hydrogenation with CTS-Pt–Fe affords the optimal results, producing 3.8% TFA at 92.1% conversion of C18:2 and no TFA was formed until the content of C18:2 was lower than 1.7%. Based on the analyses, it can be demonstrated that the preferential conversion of C18:2 to cis C18:1 and cis C18:1 to C18:0 leads to the low formation of TFA.

Study on palm oil hydrogenation for clean fuel over Ni–Mo–W/γ-Al2O3–ZSM-5 catalyst

Biodiesel, derived from vegetable oil via hydrotreating, is becoming a promising alternative energy. Novel Ni–Mo–W/γ-Al2O3–ZSM-5 catalysts were developed and firstly applied in palm oil hydrogenation process. The catalysts were prepared by extrusion method and characterized by XRD, SEM, TEM, BET, NH3–TPD, and H2–TPR. The influences of acidity on the activity, selectivity, and stability of catalysts were systematically studied. The mechanisms of deoxygenation and isomerization were discussed. The catalyst Ni–Mo–W (5wt.%–5wt.%–15wt.%)/γ-Al2O3–ZSM-5 (85wt.%−15wt.%) was confirmed as the optimum one. Finally, the key reaction parameters such as reaction temperature, pressure, liquid hourly space velocity and H2/oil volume ratio were optimized. The hydrogenation reaction path of palm oil was also proposed.

Eco-friendly lubricant by partial hydrogenation of palm oil over Pd/γ-Al2O3 catalyst

In the presence of environmental crisis, the utilization of palm oil for eco-friendly lubricant is interesting. However, the palm oil has poor oxidation resistance due to the presence of unsaturated fatty acids (oleic acid; C18:1, linoleic acid; C18:2 and linolenic acid; C18:3). The aim of this study is to improve oxidation stability of palm oil by decreasing the amount of multiple unsaturated fatty acids via partial hydrogenation over heterogeneous catalysts, and to study physicochemical properties of the hydrogenated palm oil. The partial hydrogenation of palm olein is carried out in Parr reactor, using Pd/γ-Al2O3 as catalyst. Effects of reaction conditions (temperature, pressure, time, %loading of Pd on support and amount of catalyst) on oxidation stability of synthesized oil are studied. The results show that partial hydrogenation is able to transform the multiple unsaturated fatty acids into single unsaturated fatty acids. With severe reaction conditions, the stability of product is significantly increased. However, some wax formation is observed since all double bonds in fatty acids are saturated. Too high temperature promotes the carbon chain cutting of C18 molecule to lower carbon number molecule. Then, optimal reaction conditions that increase oil stability but do not cause crystallization of oil are needed to be investigated. With the optimal conditions, the oxidation stability of palm oil increased from 13.8 to 22.8h. The effect of these parameters on the transformation of fatty acid composition in oil is also discussed.

Optimization of Pd-B/γ-Al2O3 catalyst preparation for palm oil hydrogenation by response surface methodology (RSM)

Response surface methodology was used to design and evaluate the experimental variables for Pd-B/γ-Al2O3 catalyst preparation. The catalyst was prepared by impregnation and chemical reduction. Thirteen different samples of the catalyst were prepared at different KOH concentrations and annealed at various temperatures, before applying them in palm oil hydrogenation. Hydrogenation was performed on a 0.12% Pd-B/γ-Al2O3 catalyst at a temperature of 393 K, hydrogen pressure of 500 kPa and agitation of 500 rpm for 1 h. The iodine value (IV) and trans fatty acids (TFAs) content responses were measured for each hydrogenated palm oil sample. The predicted models were verified for both responses and found to be statistically adequate. An optimization study was performed on the catalyst preparation variables for minimizing both IV and TFAs content. The Pd-B/γ-Al2O3 prepared under optimized conditions exhibited 47% higher conversion and 22% lower trans-isomerization selectivity than Escat 1241 commercial catalyst. The Pd-B/γ-Al2O3 catalyst preparation variables have a noticeable effect on palm oil hydrogenation conversion and trans-isomerization selectivity.

Effect of Annealing Temperature on Pd–B/<I>γ</I>-Al<SUB>2</SUB>O<SUB>3</SUB> Activity and Selectivity for Palm Oil Hydrogenation

Effect of Annealing Temperature on Pd–B/<I>γ</I>-Al<SUB>2</SUB>O<SUB>3</SUB> Activity and Selectivity for Palm Oil Hydrogenation

EFFECT OF PREPARATION METHOD OF Ni CATALYST USING BENTONITE AS THE SUPPORT MATERIAL

Nickel catalyst has been prepared impregnation and precipitation with nickel content of 20% and 25% each using bentonite as support material. The effects of the preparation method were studied using temperature programmed oxidation (TPO) and temperature programmed reduction (TPR) and by determination of its specific surface area. The activity of catalysts has been tested in the hydrogenation of palm oil. The catalyst with 20% of nickel and prepared by impregnation shows a single peak at 301°C, compared to catalyst with 25% of nickel prepared by the same method which has a peak at 304°C and a shoulder at 330°C. The reduction curves of both catalysts, those are prepared by impregnation, show a homogeneity indicated by a high main peak at 426°C (20% Ni) and 430°C (25% Ni). The 25% nickel catalyst by impregnation has a shoulder at 508°C. The catalysts prepared by precipitation show peaks at 508°C and 661°C for 20% of Ni and peaks at 419°C and 511°C for 25% of Ni. The reduction curves of catalysts prepared by precipitation are significantly different from each other. Those are also very different comparing to the reduction curve of impregnated catalyst. The 20% precipitated nickel catalyst has a single peak at 540°C, but the 25% precipitated nickel catalyst shows peaks at 346°C and 503°C. The differences of peak position among the reduction curves of catalysts resulted in the differences of catalyst activities with the following order 20% Ni (impregnation) > 25% Ni (impregnation) > 20% Ni (precipitation) > 25% Ni (precipitation). Keywords: bentonite, nickel catalyst, hidrogenation

Recovery of nickel from spent catalyst from palm oil hydrogenation process using acidic solutions

In this study, recovery of nickel from spent catalyst from palm oil hydrogenation process is carried out via extractive leaching process using sulfuric and hydrochloric acids. The effects of acid concentration, solid-liquid ratio, temperature and digestion time on the recovery (acid dissolution) process are investigated. It is found that sulfuric acid is the better leaching solution as compared to hydrochloric acid for recovery (dissolution) of nickel from the spent catalyst. Results from speciation modelling using VMINTEQ further imply that nickel can form sulfate complexes which are more stable than chloride complexes at concentrations higher than 1 M. The optimum conditions for maximum recovery at 85% are achieved at 67% sulfuric acid concentration, digestion time of 140 min, solid-to-liquid ratio of 1:14 and reaction temperature of 80 °C. At solution temperatures higher than 80 °C, the percentage nickel extraction is reduced. The optimization study presented here is useful for spent catalyst generators in the palm oil industry intending to recover valuable metals which may assist in reducing palm oil processing costs.

Synthesis of Fatty Alcohols from Oil Palm Using a Catalyst of Ni‐Cu Supported onto Zeolite

A series of Ni‐Cu supported onto zeolite type ZSM‐5 has been synthesized by direct hydrothermal method without template agent and characterized using XRD, FT‐IR, NRM mass, SEM, CG and N2 adsorption techniques. The catalytic performance of the obtained materials was evaluated and utilized for the hydrogenation of palm oil at 453 K and 40 atmospheres of pressure. The results show that the samples exhibited typical hexagonal arrangement of mesoporous structure with high surface area and the heteroatoms were probably incorporated into the framework of ZSM‐5. Catalytic tests show that the bimetallic incorporated materials were effective as catalysts in the hydrogenation of oil palm producing fatty alcohols typical.

Catalytic behavior of Al2O3-TiO2 supported Pd-Ru bimetallic catalyst for the partial hydrogenation of palm oil

Al2O3-TiO2 supported Pd-Ru bimetallic catalysts were prepared and characterized by X-ray photoelectron spectroscopy and X-ray diffraction (XRD) techniques. The catalytic system was evaluated in the partial hydrogenation of palm oil. Based on these results, it was deduced that core-shell model particles, with Ru cores, would be most likely formed in the bimetallic catalysts. As a result, the dispersing effect of ruthenium on palladium and the charge transfer from ruthenium to palladium may be closely related to the excellent catalytic performance. Besides, the highly dispersed TiO2 on γ-alumina support seems to be crucial for inhibiting the formation of trans fatty acid.

Hydrogenation of palm oil in near-critical and supercritical propane

Palm oil was hydrogenated in a single-phase mixture with propane and hydrogen. This was done in a small (0.5 ml), continuous fixed-bed reactor, using a 1% Pd/C catalyst. Temperature (65—135 °C), H2/TG ratio (4—50 mol/mol) and residence time (0.2—2.0 s) were varied systematically to assess the iodine value (IV) as a function of these three variables. The substrate concentration was 1 wt-%. The IV was dependent mainly on temperature and residence time. At 120 °C and a residence time of 2.0 s, full hydrogenation was achieved. The trends observed indicate that this is possible even at lower temperatures, if the residence time is increased further. Unexpectedly, the hydrogen concentration (i.e. the H2/TG ratio) was of minor importance, which can be a sign of either H2-saturation of the catalyst or a phase-split of the reaction mixture with resulting mass transport limitations for the hydrogen. Unfortunately, the catalyst showed strong signs of deactivation very early in the experiments, possibly due to impurities in the feedstock and/or to coke formation.

Hydrogenation of palm oil in near-critical and supercritical propane

Palm oil was hydrogenated in a single-phase mixture with propane and hydrogen. This was done in a small (0.5 ml), continuous fixed-bed reactor, using a 1% Pd/C catalyst. Temperature (65-135°C), H 2 /TG ratio (4-50 mcl/mol) and residence time (0.2-2.0s) were varied systematically to assess the iodine value (IV) as a function of these three variables. The substrate concentration was 1 wt-%. The IV was dependent mainly on temperature and residence time. At 120°C and a residence time of 2.0s, full hydrogenation was achieved. The trends observed indicate that this is possible even at lower temperatures, if the residence time is increased further. Unexpectedly, the hydrogen concentration (i.e. the H 2 /TG ratio) was of minor importance, which can be a sign of either H 2 -saturation of the catalyst or a phase-split of the reaction mixture with resulting mass transport limitations for the hydrogen. Unfortunately, the catalyst showed strong signs of deactivation very early in the experiments, possibly due to impurities in the feedstock and/or to coke formation.

Positional and configurational separation of fatty acid isomers by micro reversed-phase liquid chromatography with an Ag +-containing mobile phase

Different positional and configurational fatty acids, derivatised into the phenacylesters, were analyzed by reversed-phase liquid chromatography (RPLC) on micropacked fused-silica columns with an Ag +-containing mobile phase. The π-complexation strength was evaluated by plotting the selectivity coefficients ( αAg +) as a function of [Ag +]. The equilibrium constants ( K*) were determined by means of the hyperbolic dependence of the capacity factors on [Ag +]. Different fat hydrolysates and margarines taken at different stages of palm oil hydrogenation were analyzed. Data obtained with micropacked RPLC and capillary GC for the determination of the cis/ trans ratio of monoenoic acids are compared.