A one-pot and environmental-friendly route to synthesizing carbonaceous Ti-SBA-15 materials as weakly Lewis solid acids for transesterification of Jatropha oil with methanol to high-quality Jatropha biodiesel fuel (BDF) was successfully developed. The chemical environment and location of Ti species were controlled by the molar ratios of hydrochloride (HCl) to titanium tetraisoproproxide (TTIP) in the Ti precursors. With a HCl/TTIP molar ratio of 2.5, the tetrahedrally coordinated Ti species with weakly Lewis acid character were maximized in the superficial areas and they were associated with the catalytically active sites for transesterification. The thin carbon film, which was derived from direct carbonization of the P123 template originally existed in the channeling pores of as-made materials without adding sugar or sulfuric acid, could keep mesoporous silica framework safe from leaching during the processing steps to make Jatropha BDF. As a result, the carbonaceous Ti-SBA-15 materials gave excellent activity and durability in synthesis of high-quality Jatropha BDF, which fulfills with the specification of the international fuel standard, in both batch-type and continuous fixed-bed reaction systems. By contrast, the conventional Ti-SBA-15 materials with bare and amorphous silica framework were instable in synthesis of Jatropha BDF, in 3 which a large amount of silica species was eluted. Although the crystalline silica framework is relatively firmed, the commercial TS-1 zeolite gave moderate activity in synthesis of Jatropha BDF, associated with the slow molecular diffusion through the micropores. The powdered or extruded TiO 2 nanoparticles with limited numbers of tetrahedrally coordinated Ti sites gave poor activities in synthesis of Jatropha BDF, and little amounts of silica and titania species from the contaminations were eluted into the Jatropha BDF.
The paper is focused on the influence of alternative fillers on rubber compounds properties. Three different types of powder fillers, drinking water treatment sludge (DWTS), perlite and calcium carbonate, were mixed into rubber compound mixtures. The mixtures were composed of STR20, EPDM, zinc oxide, steric acid, paraffin wax, 2-mercaptobenzothiazole (MBT), sulphur, Wingstay L, and filler. The mixtures were mixed in a Kneader type mixer at temperature of 70°C and then continuously mixed using a two-roll mill at temperature of 70°C. The relationships between type and the amount of filler versus properties of rubber compounds were demonstrated. The results showed that tensile and elongation at break of rubber compounds gradually decreased with increasing the amount of filler. Rubber compounds filled with small particle size filler possessed higher tensile strength and elongation at break than those filled with large particle size filler. Values of DIN abrasion loss of rubber compounds prepared under proper mixing condition were not more than 300 mm3. Under appropriate condition, the rubber compounds with DWTS, perlite and calcium carbonate provided sufficiently high shore A hardness (not less than 50 Shore A hardness). Finally, alternative fillers such as DWTS and perlite were expected to replace calcium carbonate in normal formula.
Reflective pigment was prepared by using Fe2O3 and Al2O3 as starting materials. Fe2O3 and Al2O3 powders were mixed at 0.8:2, 1:2 and 1.2:2 mole ratio using ball milling. The mixed powders were dried and calcined at temperature of 1500°C, 1600°C and 1700°C for various soaking time at 2, 8 and 20 h. Phase data were analyzed by x-ray diffractometry. It was found that (Al1-x, Fex)2O3 presented as a new phase in calcined powders at temperature of 1500°C to 1700°C for 2 h. The other new phase such as FeAl2O4 was detected in calcined powders at temperature of 1700°C for 8 and 20 h. From the experimental results indicated that complete reaction was occurred when higher calcination temperature and longer soaking time were used, resulting in spinel structure (FeAl2O4) generated. Then, the synthesized powders were mixed with exterior paint by mass ratio of 0:100, 10:90, 20:80, 30:70 and 40:60, respectively. The mixed paints were sprayed on metal sheets. Then the coated metal sheets were exposed under 200 watts lamb and measured the temperature difference between the exposed side and opposite side. The result showed that at the ratio of 30:70 exhibited the highest temperature difference of 14°C approximately. From the result, we concluded that spinel structure (FeAl2O4) is a candidate for near-infrared (NIR) reflective pigment of exterior paint.
Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.
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