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Methane as an anthropogenic gas has an effect on the atmosphere and can be used as an alternative natural gas using adsorbent material. This research aims to determine the impact of activation conditions on the surface of fibers for zeolite-A crystal growth utilized for CH4 adsorption. Glass fiber and pineapple fiber have been treated with an alkali used in this research. The concentration of NaOH and fiber immersion time determine the activation conditions. The activation process altered the crystallinity of the surface-deposited zeolite-A. Characterization by XRD and SEM revealed that zeolite-A covered the surface of those fibers when the NaOH concentration was 4M and the immersion time was 24 h. Thermal analysis revealed that the composite of zeolite-A/fibers undergoes two weight loss processes prior to achieving stability. The methane adsorption gravimetric measurements for zeolite-A supported glass fiber (glass wool) and pineapple fiber with high crystallinities are 4.644% wt and 3.461% wt, respectively.

This research studies the impacts of microcrystalline cellulose (MCC) concentrations on the physicochemical properties of spray-dried water-in-oil-in-water (W/O/W) vitamin C double emulsion powder Four MCC concentration (1%, 1.5%, 2%, and 2.5%) were used to produce the vitamin C double emulsion powder. The results of the emulsion's creaming index, flow behaviour index, zeta value, and particle size indicated that these parameters decreased when the MCC concentration increased. Scanning electronic microscopy (SEM) analysis showed that the higher MCC concentration resulted in a smoother surface In general, the MCC concentration increased, the particle size, hygroscopicity, solubility, water content, and water activity of the double emulsion powder decreased. Double emulsion powder containing 2% MCC presented the highest level of antioxidant activity and was mostly stable after storage for 56 days. Before and after drying, transmission electron microscope (TEM) analysis of the morphological characteristics of the liquid emulsion showed that the concentration of 2% MCC in the emulsion could form a W/O/W double emulsion structure. In conclusion, the addition of MCC significantly affect the properties of vitamin C double emulsion. [ABSTRACT FROM AUTHOR]

Oil palm plantations have expanded rapidly in Southeast Asia, particularly in Indonesia and Malaysia. A lot of products, including food and other edible products, oleo-chemicals, cosmetics, personal and household care, pharmaceutical products, and biodiesels are derived from palm oil, thus making them one of the most economically important plants. After 25–30 years of age, the palms are felled and replaced due to declining oil production. Oil palm trunks (OPT) are considered significant waste products. The trunks remain on the plantation site for nutrient recycling or burning. This increases insect and fungi populations causing environmental problems for the new palm generation or air pollution due to the fire. Up till now, OPT has received less attention in research studies. Therefore, this review summarizes the utilization of OPT into products made of oil palm fibers mainly derived from OPT and its application as the substitution of wood panel products. Some research works have been carried out on oil palm fibers that are derived from OPT for exploiting their potential as raw material of composite panel products, which is the objective of this review. Areas of development are processed into various conventional composite panel products such as plywood and laminated board which are usually predominantly made of wood and bonded by synthetic resins, particleboard with binder, or binderless and cement board which is arranged with wood as a minor component. All of the products have been presented and described technically according to best knowledge of the authors and literature review. [ABSTRACT FROM AUTHOR]

To address concerns over plastics in the global environment, this project produced three wood plastics composites (WPCs) which could divert plastics from the waste stream into new materials. The three materials made had a ratio of 85%:15%, 90%:10%, and 95%:5% low density polyethylene (LDPE) to wood powder and were produced using the dissolution method. Physical and mechanical properties of each WPC were evaluated according to Japanese Industrial Standard (JIS) A 5908:2003. Their degradation in nature was evaluated through a graveyard test and assay test conducted in Coptotermes curvignathus termites. Results showed that density, moisture content, thickness swelling and water absorption of the WPCs fulfilled the JIS standard. The mechanical properties of these composites also met the JIS standard, particularly their modulus of elasticity (MOE). Modulus of rupture (MOR) and internal bonding (IB) showed in lower values, depending on the proportion of wood filler they contained. Discoloration of the WPCs was observed after burial in the soil with spectra alteration of attenuated transmission reflectance (ATR) in the band of 500–1000 cm-1 which could be assigned to detach the interphase between wood and plastics. As termite bait, the WPCs decreased in weight, even though the mass loss was comparatively small. Micro Confocal Raman Imaging Spectrometer revealed that termite guts from insects feeding on WPCs contained small amounts of LDPE. This indicated termite can consume plastics in the form of WPCs. Thus WPCs made predominantly of plastics can be degraded in nature. While producing WPCs can assist in decreasing plastics litter in the environment, the eventual fate of the LDPE in termites is still unknown. [ABSTRACT FROM AUTHOR]

In this study, the removal of urea-formaldehyde (UF) resin adhesives from waste wood particleboards (PBs) via hydrolysis was discussed, particularly the use of this application to combat environmental issues often encountered in recycling projects. Herein, the conditions required for producing PBs with poor binding properties were examined. Additionally, we determined the appropriate formaldehyde: urea (F/U) mole ratios, namely, 0.95, 1.05, and 1.15, required for generating UF resins that can be characterized and used as PB binders. The resulting values were compared with those obtained for a high mole ratio of UF resin (F/U = 2.0) as well as a commercially available PB sample for binding. Aqueous hydrochloric acid (HCl) solutions of various concentrations and water were used to leach the adhesive from the wood residues, and the effectiveness of these leaching agents was determined using a combined scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) technique in addition to the Kjeldahl method. Swelling tests were performed on the UF resins to measure the sol fraction (ω sol ) and evaluate the network behavior of the resulting resins. Our results showed that factors, such as solid content, density, viscosity, and gel time, were necessary for generating an effective adhesive; herein, we determined that a solid content between 37.17 and 56.57%, density between 1.45 and 1.54 g/cm 3 , viscosity ranging from 115-444 MPa.s, and gel time between 8.50 and 13.13 min were feasible. Whereas the physical properties of the resulting PB (i.e., the density and moisture content) fulfilled the criteria established by the Japanese Industrial Standard, as laid out in the document entitled JIS A 5908: Particleboards (2003), the mechanical properties failed to pass the aforementioned standard as low bending strength and weak internal bonding were noted for the PBs produced. The use of hydrolyzing agents successfully decomposed the UF resin adhesives by altering their nitrogen (N) content; confirmation of this was obtained through SEM-EDS analysis along with the Kjeldahl method. Swelling tests showed that despite containing a reasonable amount of nitrogen owing to its dissolution in either HCl or water, the ω sol parameter was heavily influenced by the concentration of the hardener and type of F/U mole ratio adhesive used for the PB under investigation. These results indicate that wood residues can be used as raw materials for recycling PBs., (© 2020 The Authors.)