Simulation and optimization of a supercritical extraction process for recovering provitamin A

In this work, a simulation procedure of a supercritical extraction process was developed through the use of the commercial simulator HYSYS^TM (Hyprotech Ltd.), adapting the existing units to the operating conditions typical of the supercritical extraction process. The objective is to recover provitamin A (β-carotene) from palm oil (esterified) using carbon dioxide/ethanol as the supercritical mixed solvent. This example characterizes the problem for recovering high added value product from natural sources, as the palm oil, which is desired by the market. Owing to the fact that esterified palm oil is a complex mixture, made by several components, in order to characterize this system in the simulator, it was necessary to create hypothetical components using the UNIFAC (universal function-group activity coefficients model) group contribution, because they are not present in a conventional database and, then, their physical properties must be estimated and/or predicted before the simulation. The optimization was carried out in each simulation for each equipment, in terms of operating conditions (temperature and pressure), in order to obtain the maximum recovery of carotenes. According to the results, it was possible to concentrate carotenes through two cycles of supercritical extraction with high yield. Furthermore, ethyl esters (biodiesel) were also obtained, as a byproduct of the proposed process, which can also be used as an alternative fuel, with the important characteristic that it is renewable.     

Non-functionalized oil palm waste-derived reduced graphene oxide for methylene blue removal: Isotherm,kinetics, thermodynamics,and mass transfer mechanism

The discharge of colored effluents from industries is one of the significant sources of water pollution. Therefore, there is a growing demand for efficient and low-cost treatment methods. An adsorption process with reduced graphene oxide (rGO) synthesized using a novel double carbonization and oxidation method from the natural precursor of oil palm empty fruit bunch (OPEFB) as adsorbent is a promising approach for addressing the problem. In this study, OPEFB biochar was mixed with ferrocene with a ratio of 5:1 (m/m) and oxidized under nitrogen flow at a temperature of 300 °C for 20 min, which resulted in 75.8 wt% of yield. The potential of the synthesized rGO as an effective adsorbent for dye removal from water and wastewater was explored using methylene blue (MB) as a model. Several factors were investigated, including adsorbent dosage, initial concentration, contact time, and pH, to obtain the optimum adsorption condition through batch studies. The physical and chemical characteristics of the rGO in terms of functional groups, surface morphology, elemental composition, and crystallinity phase were determined through characterization. The nonlinear isotherms were appropriated using several error functions to describe the adsorption isotherm with a maximum adsorption capacity of 50.07 mg/g. The kinetic study demonstrates that MB’s adsorption fits the PFO kinetic model and agrees with Bangham’s interpretation of pore diffusion. The adsorption mechanism was found to be physisorption on the multilayer heterogeneous surface of the rGO involving π-π interaction, hydrophobic association, and electrostatic interaction. The thermodynamics study showed that the process was spontaneous and exothermic. The mass transfer mechanism study shows that the adsorption is controlled by intraparticle diffusion and involves complex pathways. The study found that the novel non- functionalized rGO could remove cationic dyes from water and wastewater.     

Highly removal of anionic dye from aqueous medium using a promising biochar derived from date palm petioles: Characterization,adsorption properties and reuse studies

The present work investigates the preparation of promising biochar derived from date palm petioles powder (DPB) via a thermal treatment. DPB was characterized through various techniques to analyze the chemical (FTIR), morphological (SEM) and point of zero charges to investigate changes incorporated through the pyrolysis process.The adsorption of methyl orange (MO) onto the biochar was investigated using batch experiments according to different parameters which influence the adsorption process such as: initial dye concentration, equilibrium time, pH, and temperature. Isothermal and reuse studies of MO adsorption onto DPB were also investigated.Results of MO removal on DPB have demonstrated that the adsorption process was initial dye concentration-dependent, and equilibrium time was occurred in 60 min. The biochar presented high stability of MO adsorption capacity in a large domain of pH. Thermodynamic analysis of this process revealed that methyl orange adsorption was exothermic and spontaneous in nature.The experimental data were analyzed by pseudo-first-order, pseudo-second-order model, and the intraparticle-diffusion for kinetics and Langmuir, Freundlich, and Temkin models for isotherms.Kinetic adsorption followed the pseudo-second-order model and the intraparticle-diffusion within pores controlled the adsorption rate. The experimental data yielded good fits with in the following isotherms order: Langmuir > Temkin > Freundlich, The maximum adsorption capacity of MO on DPB was found 461 mg.g^?1. The reusability study reveals the possibility of the reuse of DPB for three (03) cycles of adsorption–desorption, a slight decrease in the ability of methyl orange adsorption has noticed with the increase of the number of adsorption–desorption cycles : 81.03 %, 67.84 %, and 51.72 %, respectively. The found results of the present study show that the biochar derived from date palm petioles have the potential to be used as a promising adsorbent for the treatment of MO dye.     

Pulp Enhancement of Oil Palm Empty Fruit Bunches (OPEFBs) via Biobleaching by Using Xylano-Pectinolytic Enzymes of Bacillus amyloliquefaciens ADI2

The present work reports the biobleaching effect on OPEFB pulp upon utilisation of extracellular xylano-pectinolytic enzymes simultaneously yielded from Bacillus amyloliquefaciens ADI2. The impacts of different doses, retention times, pH, and temperatures required for the pulp biobleaching process were delineated accordingly. Here, the OPEFB pulp was subjected to pre-treatment with xylano-pectinolytic enzymes generated from the same alkalo-thermotolerant isolate that yielded those of higher quality. Remarkable enhanced outcomes were observed across varying pulp attributes: for example, enzyme-treated pulp treated to chemical bleaching sequence generated improved brightness of 11.25%. This resulted in 11.25% of less chlorine or chemical consumption required for obtaining pulp with optical attributes identical to those generated via typical chemical bleaching processes. Ultimately, the reduced consumption of chlorine would minimise the organochlorine compounds found in an effluent, resulting in a lowered environmental effect of paper-making processes overall as a consequence. This will undoubtedly facilitate such environmentally-friendly technology incorporation in the paper pulp industry of today.     

Lipase immobilized on hydrophobic microporous polypropylene for the hydrolysis of palm kernel olein

Lipase (triacylglycerol ester hydrolase, EC 3.1.1.3) fromRhizopus arrhizus was immobilized in this work by adsorption on microporous polypropylene and employed for the lipolysis of palm kernel olein. The optimum operating temperature for the lipolysis reaction was determined. The reaction follows Michaelis-Menten kinetics with product competitive inhibition for substrate concentrations in the range of 0.175–0.877M. The apparentK _m and V_max were 0.42M and 691 U/mg protein, respectively. A dissociation constant of the enzymeproduct complex,K _I = 29.73 mM, for the product inhibition was also determined. Additionally, the time-courses of the reaction for various substrate concentrations were obtained and correlated sufficiently with those predicted from the theoretical rate equation for a period of up to 2 h. Experimental results indicated that discrepancies between the observed results and the predicted ones increase with reaction time.     

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

Summary 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.     

Metabolite Characterization and Correlations with Antioxidant and Wound Healing Properties of Oil Palm (Elaeis guineensis Jacq.) Leaflets via 1H-NMR-Based Metabolomics Approach

Oil palm (Elaeis guineensis Jacq.) leaflets (OPLs) are one of the major agricultural by-products generated from the massive cultivation of Malaysian palm oil. This biomass is also reported to be of potential value based on its health-improving effects. By employing proton nuclear magnetic resonance (¹H-NMR) spectroscopy combined with multivariate data analysis (MVDA), the metabolite profile of OPLs was characterized and correlated with their antioxidant and wound healing properties. Principal component analysis (PCA) classified four varieties of extracts, prepared using solvents ranging from polar to medium polarity, into three distinct clusters. Cumulatively, six flavonoids, eight organic acids, four carbohydrates, and an amine were identified from the solvent extracts. The more polar extracts, such as, the ethyl acetate-methanol, absolute methanol, and methanol-water, were richer in phytochemicals. Based on partial least square (PLS) analysis, the constituents in these extracts, such as (+)-catechin, (−)-epicatechin, orientin, isoorientin, vitexin, and isovitexin, were strongly correlated with the measured antioxidant activities, comprising ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitric oxide (NO) free radical scavenging activities, as well as with cell proliferation and migration activities. This study has provided crucial evidence on the importance of these natural antioxidant compounds on the wound healing properties of OPL.     

Phase Diagram,Electrical Conductivity,and Viscosity Study of Alpha-Sulfonated Methyl Esters Derived from Palm Stearin/1-Pentanol/Hydrocarbon/Water Systems

Microemulsion region of sodium salt alpha-sulfonated methyl ester derived from palm stearin (α-SMEPS)/1-pentanol/alkane/water systems was constructed and investigated at 30.0 ± 0.1°C. The water-in-oil (w/o) microemulsion, bicontinuous structure, and oil-in-water (o/w) microemulsion regions were determined by both conductivity and viscosity methods. Results showed that the microemulsion region decreases and moved towards (α-SMEPS f 1-pentanol) rich corner with the increase in hydrocarbon chain length of alkane from C8 to C16. The changes in alkane chain length from C16 to C8 were found to have shifted the o/w microemulsion f bicontinuous structure f w/o microemulsion transitions of α-SMEPS self-assembly to the rich water corner.     

Effect of Fiber Treatment on Dimensional Stability and Chemical Resistance Properties of Hybrid Composites

In this work, oil palm empty fruit bunch (EFB) and jute fibers were treated by 2-hydroxy ethyl acrylate (2-HEA) to enhance interaction with the epoxy matrix in hybrid composites. Hybrid composites were fabricated by the hand lay-up technique by reinforcing chemical-treated oil palm EFB and jute fibers in an epoxy matrix. Physical (density, void content, water absorption, and thickness swelling) and chemical resistance properties of treated hybrid composites were characterized. Chemically treated oil palm EFB/jute fiber reinforced hybrid composites display better dimensional stability (water absorption and thickness swelling) and chemical resistance as compared to untreated hybrid composites.