Advanced Materials Research Vol. 1133

Abstract: Abst r a c t. Polystyrene (PS) nanospheres were synthesized by emulsion polymerization using 2,2′-Azobis (2-methylpropionitrile) (AIBN) as initiator and Sodium dodecyl sulfate (SDS) act as surfactant. The size and distribution of the PS nanospheres were systematically investigated in terms of surfactant concentration. Effect of the surfactant towards to the particle size is study using SEM, FTIR and XRD. It is found that increase in Sodium dodecyl sulfate (SDS) concentration increase the reaction time thus longer time needed for the formation of the nanosphere. However their properties are comparable to the commercial Polystyrene PS nanosphere.

Abstract: The structural and field electeron emission properties of pure and Al doped ZnO nanorods synthesized on the Al substrates using sol-gel method has been studied. Al doping at different levels was achieved by adding Al₂NO₃ at 1, 3 and 5 Al at. % with respect to Zn in the synthesis solution. X-ray analysis shows that all the obtained ZnO nanorods can be indexed to the hexagonal ZnO wurtzite structure. Field electron emission measurement using the nanorods as cathode gave a trend of decreasing turn-on field values with increasing Al-doping levels, with values of 7.2 V/μm, 6.6 V/μm, 6.0 V/μm and 5.8V/μm for pure ZnO nanorods, 1, 3 and 5 at% Al-doped ZnO nanorods, respectively. The F-N plot has a linear relationship and the field enhancement factor for all samples has been obtained.

Abstract: Magnetic nanocomposite photocatalyst is an alternative approach for easy separation of catalyst from the treated water by magnetic force. This paper will discuss the performance of dye degradation using two different supported layer; Silica and Activated Carbon that shield between magnetic iron oxide (Fe₂O₃) and Titanium dioxide (TiO₂) photocatalyst. Photocatalytic activity is measure using Methylene Blue (MB) as indicator. The magnetic nanocomposite was synthesis using an evaporation indused self-assembly (EISA) approach and wet synthesis method. The photocatalyst were then characterized using Vibrating Sample Magnetometer (VSM), Brunauer-Emmet-Teller (BET), and Transmission Electron Microscope (TEM) and the effect of dye degradation were characterizing using Ultraviolet-Visible (UV-VIS) spectroscopy. The result showed that activated carbon is the good supporter compare to silica.

Abstract: Titania with a mixture of anatase, rutile and brookite nanostructures have gained much attention lately due to their high photocatalytic activity. Pure titania (TiO₂) with a mixture of anatase, rutile, brookite phase were synthesized by hydrothermal treatment using titanium isopropoxide (TTIP) and 1.0 M of urea. The titania were doped with 1wt% of single transition metal nickel (Ni), vanadium (V) and manganese (Mn) and 1 wt% bimetallic transition metal of Ni-V and Ni-Mn, respectively. Pure titania shows higher, 94 % degradation of ibuprofen (Ibp) as the presence of brookite phase in the structure. The band gap energy of titania was obtained using the Kubelka-Munk reflectance function decreased as doping a transition metallic dopant where the energy order are V<MN<Ni, respectively. Bimetallic dopant V and Mn contribute higher photocatalytic activities as decreasing band gap energy of Ni ion doping.

Abstract: The wastewater containing the spent alkanolamines and its derivatives emerging from the natural gas industries into water has become a critical concern. In the present study, Titanium dioxides was used as photocatalysts to investigate for their efficiency for the photodegradation of Diisopropanolamine (DIPA) containing wastewater under the visible light irradiation. DIPA was used as a model alkanolamine while different commercially available TiO₂ were tested for photodegradation of DIPA under the visible light source. The physico-chemical properties of the prepared photocatalysts were analyzed using different characterization techniques including X-ray diffraction (XRD), Raman spectroscopy and N₂-physisorption (BET).

Abstract: In this study, ionothermal synthesis process has been used for the preparation of two different types of Titania nanomaterials and that were utilized in the degradation of waste-water like (sulfan blue). The ionic liquid were used as 1-butyl-3-methylimidazolium dimethyl phosphate ([Bmim] DMP) as (TP) and 1-butyl-3-methypyridium dicyanamide ([Bmpm]DCN) as (TCN) respectively for the synthesis of anatase type Titania nanomaterials and confirmed with X-Ray diffraction pattern (XRD). The particle sizes and surface morphology were characterized by field emission scanning electron microsopy (FESEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET). The sizes of the particle were found to be approximately 35±5 nm from the microscopic picture analysis. The nitrogen adsorption analysis measured a surface area of 455 and 220 m² g^-1 and pore volume of 0.25 and 0.15 cm³ g^-1 for ([Bmim]DMP) and ([Bmpm]DCN) related synthesis TiO₂ nanomaterials respectively. The degradation rate of sulfan blue is higher in the presence of TP as compared to TCN owing to the larger surface area.

Abstract: Oil Palm Empty Fruit Bunch (OPEFB) contributes more than 50% of oil palm biomass wastes in Malaysia. This provides tremendous opportunities for value-added product generation from recycling and utilizing its latent capacity. In this work, the performance of physically-pretreated OPEFB fibers without any chemical treatment for Pb²⁺ removal from aqueous system was evaluated. Three different size ranges (1-5 cm, 0.5-2 mm and 0.005-0.02 mm) of raw sorbent, pH (4-10) and contact time (2-150 min) for Pb²⁺ batch adsorption were tested. The kinetic data were evaluated by the pseudo-first-order, pseudo-second-order and intra-particle diffusion model. The experimental data were well described by the pseudo-second-order model with r²=0.997. Adsorption efficiency was size-dependent with about 38% sorption increase at 0.005-0.02 mm, and reached 94% efficiency, achieved 47.49 mg/g capacity with 500 ppm Pb²⁺ at pH 7.5, in 60 min. The eco-friendly, low cost sorbent can be applied as green, effective adsorbent in waste water remediation.

Abstract: The present work aims at a better understanding of the influences of the intercalated mono-, di- and triethanolamines on the characteristics and CO₂ adsorption ability of sodium form of bentonite (Na-bentonite). The results revealed that the molar mass of intercalated amines significantly influenced the structural and surface properties as well as the CO₂ adsorption capacity of Na-bentonite. In this respect, a stepwise increase in the d-spacing of Na-bentonite with the molar mass of amine was recorded by XRD technique. However, an inverse effect of the molar mass of amine on the surface area was confirmed by BET method. CO₂ adsorption experiments on amine-bentonite hybrid adsorbents showed that the CO₂ adsorption capacity inversly related to the molar mass of amine at 25 ^ͦC and 101 kPa. Accordingly, Na-bentonite modified by monoethanolammonium cations adsorbed as high as 0.475 mmol CO₂/g compared to 0.148 and 0.087 mmol CO₂/g for that one treated with di- and triethanolammonium cations, respectively.

Abstract: Oil contamination has caused more public anxiety than other waste or spilt materials into the marine environment. Oil sorbents of high sorption capacity, biodegradable, readily available and low cost, are important for protection of water environment, especially from oil spillage. This work deals with raw and modified corn silk, an agricultural waste, as a low cost sorbent for oil-products spill cleanup in the aquatic environment. Corn silk was modified using fatty acid (oleic acid) to improve its sorption capacity. The chemical functional groups of raw and modified corn silk were analyzed by Fourier transform infrared (FTIR) spectroscopy. Kinetic tests were conducted with a series of contact times. The kinetic studies showed good correlation coefficients for a pseudo-second-order kinetic model. The oleic acid treated corn silk (OTCS) showed high degree of hydrophobicity and oil sorption capacity of approximately 10.7 and 11.90 g oil/g sorbent for Tapis and Arabian crude oil, respectively. Corn silk is a cheap waste material that can be treated to have an acceptable sorption capacity which can be used as an alternative to the commercial synthetic sorbents such as polypropylene.

Abstract: Catalytic gasification of oil sludge such as aromatic volatile organic compounds (AVOCs) (composed of benzene, toluene, xylene, ethylbenzene, trimethylbenzene, and styrene) is attractive for the industrial and environmental aspect. In this study, catalytic gasification of oil sludge was conducted in the presence of 10 wt% NiO/Al₂O₃ at temperature of 773 K in a lab-scale gasifier. Particles of NiO/Al₂O₃ in the size of 10-20 nm were detected by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) image analysis. Nitrogen adsorption analysis confirmed the surface area of 10 wt% NiO/Al₂O₃ as 130 m²/g. Finally, product gases and experimental intermediates were separated by a pressure swing adsorption (PSA) method to generate 99.9% pure hydrogen.