Mohamad Nasir Mohamad Ibrahim

A novel agricultural waste adsorbent for the removal of lead (II) ions from aqueous solutions

The present study explores the ability of modified soda lignin (MSL) extracted from oil palm empty fruit bunches (EFB) in removing lead (II) ions from aqueous solutions. The effect of contact time, point zero charge (pH(pzc)) and pH of the solution, initial metal ion concentration and adsorbent dosage on the removal process were investigated. Furthermore, the MSL is characterized by SEM, XRF, FT-IR and surface area analysis. Equilibrium adsorption isotherms and kinetics were investigated. The experimental data were analyzed by the Langmuir, Freundlich and Temkin models of adsorption. The kinetic data obtained at different initial concentrations were analyzed using pseudo-first-order and pseudo-second-order models. The results provide strong evidence to support the hypothesis of adsorption mechanism.

The use of date palm as a potential adsorbent for wastewater treatment: a review

BackgroundIn tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution.ReviewThis article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years.ConclusionStudies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.

Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and characterisation of its blend with oil palm empty fruit bunch fibers.

Poly(3-hydroxybutyrate-co-38 mol%-3-hydroxyvalerate) [P(3HB-co-38mol%-3HV)] was produced by Cupriavidus sp. USMAA2-4 in the presence of oleic acid and 1-pentanol. Due to enormous production of empty fruit bunch (EFB) in the oil palm plantation and high production cost of P(3HB-co-3HV), oil palm EFB fibers were used for biocomposites preparation. In this study, maleic anhydride (MA) and benzoyl peroxide (DBPO) were used to improve the miscibility between P(3HB-co-3HV) and EFB fibers. Introduction of MA into P(3HB-co-3HV) backbone reduced the molecular weight and improved the thermal stability of P(3HB-co-3HV). Thermal stability of P(3HB-co-3HV)/EFB composites was shown to be comparable to that of commercial packaging product. Composites with 35% EFB fibers content have the highest tensile strength compared to 30% and 40%. P(3HB-co-3HV)/EFB blends showed less chemicals leached compared to commercial packaging.

UPLC method for the determination of vitamin E homologues and derivatives in vegetable oils, margarines and supplement capsules using pentafluorophenyl column.

A sensitive and rapid reversed-phase ultra performance liquid chromatographic (UPLC) method for the simultaneous determination of tocopherols (α-, β-, γ-, δ-), tocotrienols (α-, β-, γ-, δ-), α-tocopherol acetate and α-tocopherol nicotinate is described. The separation was achieved using a Kinetex pentafluorophenyl (PFP) column (150 × 2.1mm, 2.6 µm) with both photodiode array (PDA) and fluorescence (FL) detectors that were connected in series. Column was thermostated at 42°C. Under a gradient system consisting of methanol and water at a constant flow rate of 0.38 mL min(-1), all the ten analytes were well separated in less than 9.5 min. The method was validated in terms of linearity, limits of detection and quantitation, precision and recoveries. Calibration curves of the ten compounds were well correlated (r(2)>0.999) within the range of 100 to 25,000 μg L(-1) for α-tocopherol acetate and α-tocopherol nicotinate, 10 to 25,000 μg L(-1) for α-tocotrienol and 5 to 25,000 μg L(-1) for the other components. The method is simple and sensitive with detection limits (S/N, 3) of 1.0 to 3.0 μg L(-1) (FL detection) and 30 to 74 μg L(-1) (PDA detection). Relative standard deviations for intra- and inter-day retention times (<1%) and peak areas (≤ 4%) were obtained. The method was successfully applied to the determination of vitamin E in vegetable oils (extra virgin olive, virgin olive, pomace olive, blended virgin and refined olive, sunflower, soybean, palm olein, carotino, crude palm, walnut, rice bran and grape seed), margarines and supplements.

Biomass to Bioethanol: Initiatives of the Future for Lignin

Lignin, which is one of the most abundant natural materials, represents a vastly underutilized natural polymer. With the emerging necessity to develop alternative sustainable transportation fuels, bioethanol produced from lignocellulosic biomass is considered as a viable option to petroleum-derived fuels. The effective utilization of biomass feedstock necessitates the development of cost-effective pretreatment technologies that are necessary to separate the three main biopolymers (cellulose, hemicellulose, and lignin). One of the key issues concerning the pretreatment process is the full recovery of the feedstock through optimum utilization of all lignocellulosic components, including nonsugar compounds, as marketable products. Thus, availability of high-quality lignin in large quantities should stimulate development in new lignin applications in the fields of fibres, biodegradable polymers, adhesives, and surface treatment (rust converter).

THIN-LAYER CHROMATOGRAPHY OF AMINO ACIDS: A REVIEW

Thin-layer chromatography is a versatile separation technique and is compatible to almost all types of compounds available in nature. This review presents numerous chromatographic systems developed for the analysis of amino acids. The stationary phases, solvent systems, and detection reagents used by the various chromatographers are incorporated in this review. From the available literature, it is obvious that amino acids have been greatly analyzed by thin-layer chromatography.

Monomers of lignin as corrosion inhibitors for mild steel: study of their behaviour by factorial experimental design

Abstract This paper investigates the role of monomers of lignin on the corrosion inhibition of mild steel and their main and interaction effects on the corrosion parameters. A combination of statistical analysis and interaction contour plots has been employed to obtain an in depth understanding of the corrosion variables. Electrochemical tests were performed on three lignin monomers namely p-coumaric acid (CA), ferulic acid (FA) and hydroxybenzaldehyde (HB) on mild steel in near neutral solution. The CA and FA showed better inhibition of more than 70%, especially at higher concentrations. A full factorial method was used to study the main and interaction effects on these monomers. P-coumaric acid and FA have shown good inhibition with the greatest interaction effect with each other on the inhibition efficiency. Although HB had the lowest effect on inhibitor efficiency (%IE), its interaction with other monomers was significant. An empirical equation has been derived from test results to describe the relationship between the variables. Analysis of variance on the corrosion parameter shows a normalised distribution and confirms the suitability of this model. Scanning electron micrographs also showed an increase in inhibition with the metal surface with increasing inhibitor concentration.

Separation and Characterization of the Vanillin Compound from Soda Lignin

The separation of vanillin from soda lignin that was extracted from black liquor of oil palm empty fruit bunches (EFB) using 20% sulfuric acid is presented in this paper. The degradation of soda lignin using alkaline nitrobenzene oxidation was carried out at 165 ° C for 3 hours in a 2 M NaOH and nitrobenzene solution. One of the major products obtained from the breakdown of lignin is vanillin. The crys- tallization process was used as a method to separate vanillin from other compounds. Based on the solubility of vanillin in acetone, 15 mL of acetone was added to the residue of the oxidized products. The mixture was slowly heated to 40 - 50 ° C for 15 minutes until the vanillin crystalline precipitated. A yield of about 1.6% vanillin was isolated from 50 mg sample of lignin. The isolated compound was analyzed utilizing high performance liquid chromatography, Fourier transform infrared spec- trophotometry (FTIR) and nuclear magnetic resonance ( 1 H-NMR). The results of the characterization studies proved that the isolated compound was vanillin.

Developing a Proficient Relative Permeability Resource From Historical Data

Having reliable and readily accessible relative permeability information is a problem for many reservoir engineers. In the absence of laboratory measured data or in the case when a more general representation of fluid flow in a reservoir is needed, empirical relative permeability correlations become useful. 416 sets of relative permeability data were obtained from published literature and various industry sources, and were modified to fit a common format. The central database thus constructed allows relative permeability data to be easily retrieved and processed. Categorizing and modifying the original data for applicability to similar systems is considered, allowing for variations in connate water, residual oil, and critical gas saturations. Information such as fluid type, wettability, lithology, geographical location, and method of measurement is used to search applicable results. A linear regression model approach is employed to develop prediction equations for water-oil, gas-oil, gas-water, and gascondensate relative permeability from the measured data. Improved equations were developed for water-oil and gas-oil systems based on formation type and wettability. Additionally, general equations for gas-condensate and gas-water systems were formulated. Craig’s rule for determining wettability has been modified to include a wider range of relative permeability data. Available data has increased significantly since the last published work in this area. The prediction equations are compared with previously published correlations. The database and prediction equations may be downloaded at no charge from a University of Missouri-Rolla web site.

Antioxidant and anticorrosive properties of oil palm frond lignins extracted with different techniques

ContextOil palm (Elaeis guineensis Jacq.) fronds are produced as waste during the harvest of oil palm fruits. It mainly consists of cellulose, lignin, and hemicelluloses. Lignins like other polyphenols are potent free radical scavengers and are considered to be a valuable source of antioxidant phenolic compounds.AimsThe aim was to quantify the antioxidant properties of lignins extracted from oil palm biomass using Kraft, soda, and organosolv pulping. The potential of the extracted lignins as inhibitors of mild steel corrosion was also assessed.MethodsGround and dried 1–3-mm-mesh-size oil palm fronds were submitted to Kraft, soda, and organosolv pulping in rotary digesters. The extracted lignin was characterized and oxygen uptake was measured. Anticorrosion properties of extracted lignins were monitored via electrochemical measurements and surface analysis.ResultsSoda-extracted lignins displayed the highest antioxidant activities as compared to Kraft and ethanol organosolv lignins. The highest inhibition of corrosion of mild steel was reached in the presence of soda-extracted lignins.ConclusionOil palm fronds are potential sources of lignins usable as green antioxidant for corrosion inhibition of mild steel.