a b s t r a c tMetal based-zeolite catalysts were successfully prepared by two different methods including ionexchange and wet impregnation. HZSM-5 synthesized by hydrothermal method at 160 C was used as a support for loading metals including Co, Ni, Mo, Ga and Pd. The metal/HZSM-5 had surface area and pore size of 530e677 m 2 /g and 22.9-26.0 Å. Non-and catalytic fast pyrolysis of Jatropha residues using metal/HZSM-5 were studied using an analytical pyrolysis-GC/MS at 500 C. Non-catalytic pyrolysis vapors contained primarily high levels acid (50.7%), N-containing compounds (20.3%), other oxygenated compounds including ketones, alcohols, esters, ethers, phenols and sugars (25.0%), while generated small amount of aromatic and aliphatic hydrocarbons of 3.0% and 1.0%. The addition of synthesized metal/ HZSM-5 improved the aromatic selectivity up to 91e97% and decreased the undesirable oxygenated (0.6e4.0%) and N-containing compounds (1.8e4.6%). The aromatic selectivity produced by metal-ion exchanged catalysts was slightly higher than that produced by impregnated ones. At high catalyst content (biomass to catalyst ratio of 1:10), Mo/HZSM-5 showed the highest aromatic selectivity of 97% for ion-exchanged catalysts and Ga/HZSM-5 revealed the highest aromatics of 95% for impregnated catalysts. The formation of aromatic compounds could be beneficial to improve calorific values of biooils. The presence of metal/HZSM-5 from both preparation methods greatly enhanced MAHs selectivity including benzene, toluene, and xylene (BTX), while substantially reduced unfavorable PAHs such as napthalenes.

HZSM-5 with high surface area of 625 m 2 /g was successfully synthesized by hydrothermal method at 160°C for 72h. The metal promoted on HZSM-5 catalyst was prepared by liquid ion exchange method. From XRD results, the addition of metals such as Co and Ni did not change the HZSM-5 structure. The metal/HZSM-5 showed lower crystallinity and surface area than the parent HZSM-5 because of the metal dispersion on the HZSM-5 surface. The metal contents of Co/ HZSM-5 and Ni/HZSM-5 detected by EDX were less than 1wt%. Catalytic fast pyrolysis of Jatropha waste using HZSM-5 and metals/HZSM-5 was investigated in terms of biomass to catalyst ratios (1:0, 1:1, 1:5 and 1:10) and types of metals (Co and Ni). From the results, it can be concluded that both biomass to catalyst ratios and the presence of metals had an effect on the increase in aromatic hydrocarbons yields as well as the decrease in the oxygenated and Ncontaining compounds. Both Co/HZSM-5 and Ni/HZSM-5 promoted the production of aliphatic compounds. Additionally, the PAHs compounds such as napthalenes and indenes, which caused the formation of coke, could be inhibited by metal/HZSM-5, particularly, Ni/HZSM-5. Among catalysts, Ni/HZSM-5 showed the highest hydrocarbon yield of 97.55% with N-containing compounds remained only 1.78%. The formation of hydrocarbon compounds increased the heating values of bio-oils while the elimination of the undesirable oxygenated compounds such as acids and ketones could alleviate problem regarding acidity and instability in bio oils.

Use of waste as raw material for producing porous carbon was investigated in this work. Physic nut (Jatropha curcas L.) residue from oil extraction for biodiesel production was pyrolyzed at 400-800 °C with hold times of 15, 120, and 240 min to obtain char precursors. Activated carbon, with favorable Brunauer-Emmett-Teller surface area in a narrow range, was prepared by soaking these chars in concentrated KOH, H 3 PO 4 , as well as a pure CO 2 gas flash activator. The maximum specific surface area of 532.30 m 2 g -1 was developed for the alkaline-treated sample. The carbon fraction of activated materials was as much as 90 wt %, significantly higher than the char precursor. Mesopore of 2-50 nm and total pore volumes of the materials were also significantly enhanced by these activations. Nitrogen adsorption isotherms of physic-nut-waste-activated carbons indicated that they were mainly mesopores. Pores of char activated by KOH and H 3 PO 4 are irregular, of different shapes and sizes, and the macropores seemed to be connected to mesopores, especially for the KOHactivated case. Surface analysis of pyrolyzed and activated char using Fourier transform infrared spectroscopy indicated main functional groups that are considerably different to those of activated materials, which may lead to greater adsorption potential of activated samples. However, functional groups on each activated carbon are quite similar even with different activation processes. According to the data obtained, physic nut residue pyrolyzed at 800 °C and followed by KOH activation could be used as a low-cost adsorbent with favorable surface properties.

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The objective of this study was to catalytically upgrade bio-oil from organic vapors of Jatropha wastes using Py-GC/MS. Catalytic testing included Al2O3, ZrO2, TiO2 (rutile, T1) and TiO2 (anatase, T2) supporter catalysts modified with transition metals (Pd, Ru or Ni) by impregnation method. In non-catalytic runs, the main vapor products were fatty acids (60.74%). With the presence of Al2O3 based catalysts, carboxylic acids were obviously reduced to 0.76-19.61% while hydrocarbons were the main products (42.00-64.06%). Comparing among four supporters, total hydrocarbon yields increased with presence of all catalysts. Higher yields were obtained by T2>Al2O3>CA>NiCA>RuCA catalysts. Al2O3 and T2 supports were the most effective for increased hydrocarbons while decreased oxygenated compounds (15%) which is one of the primary aims of this study. The result indicating that high surface area resulted in better catalytic activity but also adversely promoted N-compounds. Therefore these catalysts can be applied to improve properties of pyrolytic products.

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