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Regenerated cellulose membrane was successfully formed by coagulating cellulose solution in sulphuric acid, ammonium sulphate and distilled water. Drying method plays an important role in determining the final properties of the regenerated cellulose. Regenerated cellulose membranes were dried using three methods which were air dry, freeze dry and freezer dry. These drying methods have resulted on membrane characteristics such as water absorption. This study found that freeze dried membrane was able to re-absorb water up to 49%, while air dried and freezer dried membrane reabsorbed water up to 40 and 45% respectively. [ABSTRACT FROM AUTHOR]

The main goal of this work was to use rice straw nanocellulose in the production of nanocomposites using epoxy resin. The chemo-mechanical treatment was used to produce rice straw nanocellulose powder. The treatment was done to evaluate the effect of such treatment on the performance of produced nanocomposites. The morphology and crystallinity of the nanocomposites was further observed. The Field Emission Scanning Electron Microscopy (FESEM) images show that the surface morphology of rice straw nanocellulose nanocomposite was homogenous in epoxy compared to rice straw powder nanocomposite. X-ray Diffraction (XRD) pattern showed that the addition of 1% of filler (rice straw powder and rice straw nanocellulose) in the epoxy matrix does not result in any significant changes on its crystallinity. Thus, the analysis provided the information that there was no transformation to the trans-crystalline phase in the system interface. [ABSTRACT FROM AUTHOR]

Dissolution of kenaf core cellulose was undergone in NaOH/Urea solvent and the cellulose solution was casted with three different thicknesses (0.04 mm, 0.06 mm and 0.07 mm) followed by coagulation in 5% of H2SO4 to form regenerated cellulose membrane. The XRD results showed that the crystallinity index (CrI) of kenaf core cellulose membrane decreased after been regenerated into cellulose II. The surface morphology showed that the pores of the membrane became smaller as the thickness of cellulose membrane increased. The transparency tests demonstrated the thinner samples (0.04 mm) gave higher light transmittance than the thickest samples (0.07 mm). The kenaf core membrane with 0.07 mm thickness possessed highest tensile strength and breaking elongation at σ = 33.48 and ε = 8.03 relatively and also exhibited the largest pore size. [ABSTRACT FROM AUTHOR]

In this paper a series of nanostructured magnetic cobalt ferrite were synthesized by hydrothermal method using stable ferric and cobalt salts with sodium hydroxide as the surfactant. X-ray Diffraction (XRD) and field-emission scanning electron microscopy (FESEM) were employed to evaluate the structural properties of synthesized nanoparticles. X-ray diffraction analysis confirmed that the cobalt ferrite nanoparticles had a single-phase spinel structure. From the analysis of the powder X-ray diffraction patterns, the average crystallite size was calculated using the Scherrer formula. The results showed that the average crystallite size is in the range of 63-74 nm increases, depending on the annealing temperature and time. [ABSTRACT FROM AUTHOR]

Cellulose was extracted from kenaf core pulp by a series of bleaching processes and subsequently dissolved using an alkaline NaOH/urea solvent at low temperature. The produced cellulose solution was coagulated with H2SO4 at concentration from 5 to 12 wt% to produce a series of regenerated cellulose (RC) membranes. The surface morphology, structure and physical properties of the membranes were measured with variable pressure scanning electron microscope (VPSEM), X-ray diffraction (XRD), UV-vis spectrophotometer and tensile testing. The results from VPSEM revealed that the pore size of the membranes changed as a function of the concentration of H2SO4 coagulant. RC membranes coagulated with relatively dilute H2SO4 solution exhibited better mechanical properties. Thus, this work provided a promising way to prepare cellulose membranes with different pore sizes and good physical properties. [ABSTRACT FROM AUTHOR]

Concentration of extracted free sugar in the oil palm trunk from inner and outer part was analysed using High Performance Liquid Chromatography (HPLC). The highest sugar concentration was glucose and total sugar content was higher in the inner part than the outer part. The methanolysis reaction of extracted sapfrom inner and outer part of core oil palm trunk using phosphomolybdic acid and aluminium sulphate was done using methanol as solvent, 2.5 h and at 160°C. In this reaction, conversion of total sugar produced high concentrations of pentanoic acid, 4-oxo-, methyl ester and low 5- hydroxymethylfurfural using aluminium sulphate as catalyst. [ABSTRACT FROM AUTHOR]

We report on the effect of using reducing agents with different chain-length on the synthesis of iron oxide nanoparticles by thermal decomposition of iron (III) acetylacetonate in 1-octadecene. This modification allows us to control the shape of nanoparticles into spherical and cubic iron oxide nanoparticles. The highly monodisperse 14 nm spherical nanoparticles are obtained under 1,2-dodecanediol and average 14 nm edge-length cubic iron oxide nanoparticles are obtained under 1,2-tetradecanediol. The structural characterization such as transmission electron microscope (TEM) and X-ray diffraction (XRD) shows similar properties between two particles with different shapes. The vibrating sample magnetometer (VSM) shows no significant difference between spherical and cubic nanoparticles, which are 36 emu/g and 37 emu/g respectively and superparamagnetic in nature. [ABSTRACT FROM AUTHOR]

Wholestalk Kenaf were liquefied using phenol as liquefaction medium, while sulfuric acid was used as liquefaction catalyst. Kenaf liquefaction process was performed in a glass flask equipped with thermometer, condenser systems and mechanical stirrer. The efficiency of the liquefaction process depended on the raw materials and parameter used. Liquefaction of kenaf were carried out with different phenol/kenaf ratios at 150 °C using 3% of sulfuric acid. Characterization was carried out on liquefaction kenaf residues to study their morphology properties. Liquefaction data showed that the liquefaction residue with parameter percent of sulfuric acid 4 %, F/K ratio 2.5/1.0, 90 minutes and 170 °C gave optimum conversion percentage as high as 89.04% of liquefied kenaf. [ABSTRACT FROM AUTHOR]

Tannin was extracted from gelam bark and used to produce corrosion inhibitor for mild steel. Tannin was extracted from gelam bark using 70% aqueous acetone for 6 hour. Tannin powder was characterization using fourier transform infrared spectroscopy to analyse chemical component in tannin and Scanning electron microscope (SEM) for tannin physical structure. The tannin effect on the corrosion inhibition of mild steel has been investigated in 1Mol HCl solution for 6 hour followed ASTM. The weight loss method were applied to study the mild steel corrosion behavior in the present and absend of different concentration of tannin (250, 300, 350 )ppm. Tannin act good inhibitor as corrosion inhibitor for mild steel in acid medium. Surface morphology of carbon steel with and without inhibitor was investigated by scanning electron microscopy [ABSTRACT FROM AUTHOR]

In this current study, the soda lignins from empty fruit bunch (EFB) and kenaf core were recovered by two step precipitation method. The objective of this research is to study the purity of lignin by washing the lignins with acidified water. The purified lignins were undergone characterization by FT-IR, Uv-Vis and XRD. The FT-IR analysis shows that kenaf core has Guaiacyl(G) and Syringyl(S) unit meanwhile EFB has Hydroxyphenyl(H), Guaiacyl(G) and Syringyl(S) unit of lignin. As for XRD analysis, the non-purified shows that the existence of impurities which is salt (NaCl). The UV analysis shows the higher absorbance which lead to the purity of lignin. [ABSTRACT FROM AUTHOR]

Pure rutile phase titanium oxides (TiO2) nanocrystals were synthesized via hydrothermal method with titanium tetrachloride (TiCl4) and water (H2O) treated in an autoclave. The particle size and phase assemblages were characterized using Scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Band gap energy (Eg) of the nanocrystals was estimated from the Ultra violet - visible light (UV-vis) absorption spectra. It was demonstrated that TiO2 nanocrystals can be prepared through increasing of temperature and period of treatment. It is believed that the presence of acid chloride (HCl) as by-product during the hydrolysis played an important role in controlling the growth of morphology and crystal structures. The Eg of the samples were estimated from the plot of modified Kubelka-Munk function were in the range of 3.04 - 3.26eV for the samples synthesized at temperature ranging from 50 to 200°C for 16 hours. [ABSTRACT FROM AUTHOR]

Preliminary study on microwave-assisted hydrolysis of deproteinated palm kernel cake (DPKC) to produce oligosaccharides using succinic acid was performed. Three important factors, i.e., temperature, acid concentration and reaction time, were selected to carry out the hydrolysis processes. Results showed that the highest yield of DPKC-derived oligosaccharides can be obtained at a parameter 170 °C, 0.2 N SA and 20 min of reaction time. [ABSTRACT FROM AUTHOR]

Calcium carbonate (CaCO3) has three different crystal polymorphs, which are calcite, aragonite and vaterite. In this study, effect of reaction temperature on polymorphs and crystallite structure of CaCO3 was investigated. X-ray powder diffraction (XRD), fourier transform infrared (FTIR), and variable pressure scanning electron microscope (VPSEM) were used to characterize the obtained CaCO3 particles. The obtained results showed that CaCO3 with different crystal and particle structures can be formed by controlling the temperature during the synthesis process. [ABSTRACT FROM AUTHOR]

A preliminary study on the reaction between aqueous resole type resinified liquefied palm oil empty fruit bunches fibres (RLEFB) with epoxidized natural rubber (ENR) . Liquefaction of empty fruit bunches (EFB) is carried out at different ratio of phenol to EFB (P:EFB). Resole type phenolic resin is prepared using sodium hydroxide (NaOH) as the catalyst with the ratio of liquefied EFB (LEFB) to formaldehyde (LEFB:F) of 1:1.8. 50% epoxidation of epoxidized natural rubber (ENR-50) is used to react with resole resin by mixing with ENR with aqueous resole resin. The cured resin is characterized with FT-IR and SEM. Aqueous system have been found to be unsuitable medium in the reaction between resin and ENR. This system produced a highly porous product when RLEFB/ENR resin is cured. [ABSTRACT FROM AUTHOR]