@article {1660, title = { Modification of oil palm fronds lignin by incorporation of m-cresol for improving structural and antioxidant properties }, journal = { INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES }, volume = {104}, year = {2017}, pages = {251-260}, abstract = {

Lignin extracted from oil palm fronds (OPF) underwent chemical modification by incorporating m-cresol into the lignin matrix. This study reports on the physicochemical properties and antioxidant activity of unmodified autohydrolyzed ethanol organosolvlignin (AH EOL) and the modified autohydrolyzed ethanol organosolv lignin (AHC EOL). The lignin samples were analyzed by FFIR, H-1 and C-13 NMR spectroscopy, 2D NMR: HSQC spectroscopy, CHN analysis, molecular weight distribution analysis; GPC and thermal analysis; DSC and TGA. The lignin modification has reduced the hydrophobicity of its complex structure by providing better quality lignin with smaller fragments and higher solubility rate in water (D-AHCEOL.: 42\%\> D-AHEOL: 25\%). It was revealed that the modification of lignin has improved their structural and antioxidant properties, thus venture their possible applications.

}, url = {https://hal.univ-lorraine.fr/hal-01765057}, author = {N.A. SA{\textquoteright}DON and A.A. RAHIM and M.N.M. IBRAHIM and N. BROSSE and M.H. HUSSIN} } @article {1657, title = { The capability of ultrafiltrated alkaline and organosolv oil palm (Elaeis guineensis) fronds lignin as green corrosion inhibitor for mild steel in 0.5 M HCl solution }, journal = { MEASUREMENT }, volume = {78}, year = {2016}, pages = {90-103}, abstract = {

The inhibitive effect of ultrafiltrated oil palm fronds (OPF) lignins on the corrosion of mild steel in 0.5 M HCl solution has been investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PP) and weight loss measurement. The presence of smaller lignin fractions reduces remarkably the corrosion rate of mild steel. The highest corrosion inhibition efficiency for all ultrafiltrated lignins were attained at maximum concentration of 500 ppm (IEP.Soda: 87\% \> IEP.Organosolv: 83\% \> IEP.Kraft: 81\%). The results from this corrosion test clearly reveal that all ultrafiltrated lignins behaved as a mixed-type inhibitor with predominant anodic (organosolv lignin) or cathodic (alkaline lignin) effectiveness. It was deduced that the inhibition process was spontaneous and the inhibitors were mainly physically adsorbed onto the mild steel surface.

}, author = {M.H. HUSSIN and A.A. RAHIM and M.N.M. IBRAHIM and N. BROSSE} } @article {1557, title = {Improved corrosion inhibition of mild steel by chemically modified lignin polymers from Elaeis guineensis agricultural waste}, journal = {MATERIALS CHEMISTRY AND PHYSICS}, volume = {163}, year = {2015}, pages = {201-212}, abstract = {

This article describes that the modification of lignin by incorporation of aromatic scavengers (2-naphthol: AHN EOL and 1,8-dihydroxyanthraquinone: AHD EOL) during delignification process has improved the physical properties of the lignin fractions. Smaller fragments of lignin with high phenolic -OH content, increased solubility and antioxidant activity have led to improved inhibitive property of the modified lignin. The inhibition efficiency (84-93\%) of both modified lignin (500 ppm) were observed to be better than unmodified organosolv lignin (EOL). It was deduced that the inhibition process was spontaneous and the inhibitors were mainly physically adsorbed onto the mild steel surface.

}, author = {M.H. HUSSIN and A.A. RAHIM and M.N.M. IBRAHIM and N. BROSSE} } @article {1544, title = {Preparation and Characterization of Lignin Polyols from the Residues of Oil Palm Empty Fruit Bunch}, journal = {BIORESOURCES}, volume = {10}, year = {2015}, pages = {7339-7352}, abstract = {

In this work, lignin polyols were prepared from the liquefaction of kraft lignin and from the direct liquefaction of Elaeis guineensis lignocellulosic waste. The liquefaction reaction was performed with polyhydric alcohols using sulfuric acid as catalyst at 160 degrees C. The physical and chemical characterizations of lignin and lignin polyols were conducted by elemental analysis, Fourier transform-infrared spectroscopy, H-1 and C-13 nuclear magnetic resonance (NMR) spectroscopy, molecular weight distribution, and thermogravimetric analysis (TGA). Quantitative C-13 NMR showed that all aliphatic hydroxyl group values of polyols noticeably increased with the use of the two methods compared to kraft lignin. The average molecular weight analysis of the liquefied product showed that it exhibited high molecular weight compared to kraft lignin. Both structural and thermal characteristics suggest that lignin polyols would be a good substitute for kraft lignin in the synthesis of polymeric compounds such as environmentally friendly resins or wood adhesives, as it presents higher amounts of activated free ring positions, higher molecular weight, and high thermal stability.

}, url = {https://hal.archives-ouvertes.fr/LERMAB-UL/hal-01598213}, author = {A.H. FARIS and M.N.M. IBRAHIM and A.A. RAHIM and M.H. HUSSIN and N. BROSSE} }