Nurul Syuhada Sulaiman

Application of optimized large surface area date stone (Phoenix dactylifera ) activated carbon for rhodamin B removal from aqueous solution: Box-Behnken design approach.

Box-Behnken model of response surface methodology was used to study the effect of adsorption process parameters for Rhodamine B (RhB) removal from aqueous solution through optimized large surface area date stone activated carbon. The set experiments with three input parameters such as time (10-600min), adsorbent dosage (0.5-10g/L) and temperature (25-50°C) were considered for statistical significance. The adequate relation was found between the input variables and response (removal percentage of RhB) and Fisher values (F- values) along with P-values suggesting the significance of various term coefficients. At an optimum adsorbent dose of 0.53g/L, time 593min and temperature 46.20°C, the adsorption capacity of 210mg/g was attained with maximum desirability. The negative values of Gibbs free energy (ΔG) predicted spontaneity and feasibility of adsorption; whereas, positive Enthalpy change (ΔH) confirmed endothermic adsorption of RhB onto optimized large surface area date stone activated carbons (OLSADS-AC). The adsorption data were found to be the best fit on the Langmuir model supporting monolayer type of adsorption of RhB with maximum monolayer layer adsorption capacity of 196.08mg/g.

Fungal Resistance of Particleboard Made Using Glutardialdehyde Modified Corn Starch as the Binder with the Aid of Urea Formaldehyde Resin

Particleboard is a popular wood composite made using mixtures of wood particles and resin, binder or adhesives, pressed at high temperature to cured. Despite its popularity, formaldehyde-based adhesives used in the formulations lead to cancerous effect as the formaldehyde fumes released from the unreacted chemicals travel into human lungs. Therefore this study tries to reduce the utilization of formaldehydebased resin by replacement of a significant portion of the binder with glutardialdehyde modified corn starch as the binder. However, this practice could lower the durability of the particleboards against biological attack. Therefore, this study evaluates the fungal resistance of the particleboard panels. Panels were manufactured using 83:15:2 ratio of wood, corn starch-modified with glutardialdehyde and formaldehyde resin, respectively, as an improvement. Four types of wood-degrading fungal were chosen including Trametes versicolor, Formitopsis palustris, Schizophyllum commune and Pycnoporus sangineus. Some of the particleboard showed a little increased in fungal resistance when 2% urea formaldehyde was added, compared to using glutardialdehyde modified corn starch and starch only as the binder. Nine out of twelve samples showed a decrement in fungal degradation by using glutardialdehyde modified starch as the binder. Meanwhile, 6 out of 12 samples showed higher fungal resistance after additional of 2% urea formaldehyde in the binder formulation. Based on the results, combination of modified corn starch and urea formaldehyde resin could have a potential to be used in particleboard making without reducing the initial resistance towards fungal attack.

Effect of Urea Formaldehyde Addition to the Dimensional Stability of Particle Board Made Using Glutardialdehyde Modified Corn Starch as Binder with FT-IR Analysis

The objective of the study was to evaluate the dimensional stability of experimental particle board panels made from rubberwood (Hevea brasiliensis) using modified starch as binder. Panels were manufactured using 15% corn starch modified with glutardialdehyde and 13% modified starch with 2% Urea Formaldehyde resin as improvement. The particle boards were tested for their dimensional stability towards moisture. Results found that the 2% replacement of modified starch with urea formaldehyde resin showed increment in dimensional stability compared to using glutardialdehyde modified corn starch only as the binder, recorded at 39.38 % and 23.47 % for particleboard with 0.80 g/cm3 density after exposed to 75% and 95 % relative humidity. Therefore, this study indicated that combination of modified corn starch and urea formaldehyde resin can have a potential to be used as an improved binder to produce particle board panels with accepted properties.The objective of the study was to evaluate the dimensional stability of experimental particle board panels made from rubberwood (Hevea brasiliensis) using modified starch as binder. Panels were manufactured using 15% corn starch modified with glutardialdehyde and 13% modified starch with 2% Urea Formaldehyde resin as improvement. The particle boards were tested for their dimensional stability towards moisture. Results found that the 2% replacement of modified starch with urea formaldehyde resin showed increment in dimensional stability compared to using glutardialdehyde modified corn starch only as the binder, recorded at 39.38 % and 23.47 % for particleboard with 0.80 g/cm3 density after exposed to 75% and 95 % relative humidity. Therefore, this study indicated that combination of modified corn starch and urea formaldehyde resin can have a potential to be used as an improved binder to produce particle board panels with accepted properties.

Glutardialdehyde Modified Corn Starch – Urea Formaldehyde Resin as a Binder for Particleboard Making

The objective of the study was to characterize and to evaluate physical and mechanical properties of experimental particleboard panels made from rubberwood (Heveabrasiliensis) using modified starch-urea formaldehyde as binder. Panels were manufactured using 13% corn starch modified with glutardialdehyde with addition of 2 % urea formaldehyde resin and tested for their physical and mechanical properties. All of the particleboards satisfied the Japanese Industrial Standard which required 2000 N/mm2, 8.0 N/mm2 and 0.15 N/mm2 for modulus of elasticity, modulus of rupture and internal bonding strength, respectively. The mechanical properties were comparable to those made using 15 % urea formaldehyde resin with reduction of formaldehyde fume was over 50 %.

Antibacterial Activity of Different Biomass Components of Cerbera odollam and their Potential to Be Used as New Preservative for Wood Based Products

Cerbera odollam’s tree parts were extracted with methanol and further fractionated using n-hexane, ethyl acetate and ethanol, followed by antibacterial assay against Bacillus subtilis, Bacillus licheniformis, Escherichia coli and Pseudomonas aeruginosa. Hexane soluble parts from flower, fruit, leaf, wood, bark and ethyl acetate soluble part from bark showed antibacterial activity against Bacillus subtilis. Hexane soluble parts from leaf and bark and ethyl acetate soluble parts from wood showed antibacterial activity against Bacillus licheniformis. All fractions appeared ineffective on Escherichia coli and Pseudomonas aeruginosa. Screened extracts were analysed using FTIR. Experiments were continued with impregnation of methanolic extracts of Cerbera odollam into Melamine-urea formaldehyde (MUF) particleboards, Phenol-resorcinol formaldehyde (PRF) particleboards and solid wood samples followed by exposure to wood-boring beetles and natural decaying.