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The aluminosilicate version of SSZ-31 ([Al]-SSZ-31) zeolite was synthesized by a new route including phasetransformation, wherein an aluminosilicate analog of beta zeolite ([Al]-BEA) was used as a precursor and 1,1,1,8,8,8-hexaethyl-1,8-diazoniaoctane dihydroxide was used as a structure-directing agent (SDA). [Al]-BEA precursors synthesized by two routes, viz. the hydrothermal (HTS) and dry-gel conversion (DGC) method, were employed for the synthesis. [Al]-SSZ-31 with a low output SiO 2 /Al 2 O 3 ratio crystallized only when the precursor (SiO 2 /Al 2 O 3 = 30), prepared by DGC method, was employed. Precursors synthesized by the HTS method produced highly crystalline samples, however, only in the high silica region. In general, [Al]-SSZ-31 samples over a wide range of SiO 2 /Al 2 O 3 ratios could be synthesized using a precursor route. During crystallization, a phase transformation from [Al]-BEA to [Al]-SSZ-31 was observed, indicating dissolution of the beta phase, followed by its redirection towards the SSZ-31 phase in the presence of SDA. An increase in gel water helped to produce pure [Al]-SSZ-31. [Al]-SSZ-31 was found to crystallize in NaOH/SiO 2 window of 0.040-0.056. Scanning electron microscopy (SEM) showed plate-like crystals of about 5 mm in size. 13 C CP MAS NMR indicated that the SDA was intact inside the pores during crystallization. Furthermore, the samples were also characterized by 29 Si and 27 Al MAS NMR in addition to X-ray diffraction (XRD), temperatureprogrammed desorption of ammonia (NH 3-TPD), SEM, etc.

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The effects of seeding on synthesis of MCM-22 (MWW) have been studied by the dry gel conversion (DGC) method. Highly reproducible crystalline MWW zeolite could be obtained by DGC method, using seeds of calcined sodium MWW with SiO 2 /Al 2 O 3 ¼ 31. Crystallization of MWW phase was completed in the presence of seeds (2 mass% against SiO 2 ) at 150 C within two days. The small amount of seed (0.25 mass% against SiO 2 ) was sufficient for the required phase formation of MWW. The MWW with SiO 2 /Al 2 O 3 ratio from 35 to 66 was obtained as pure phase; however, the crystallinity of MWW decreased with further increase in the ratio: products were contaminated with impurities.The catalytic properties of MWW were examined in the skeleton isomerization and the cracking of hexane, and compared to zeolites such as BEA, MFI, and MOR. The catalytic activities were in the order: MFI>BEA>MWW)MOR; however, the selectivity for the isomerization were in the order: BEA>MWW>MFI. These catalytic properties were due to the differences of structures and acid strength of zeolites.

The sulphur content in diesel oil must be less than 0.5% by weight of diesel oil, because the high sulphur content will accelerate the occurrence of wear and tear on the engine cylinder walls. For this reason, desulphurization is carried out to reduce sulphur content in diesel oil. The process of desulphurisation of diesel oil causes a decrease in the lubricating power of diesel oil to the engine so that the addition of additives is needed. In this research, bioaditive substances in the form of 2-hydroxy propyl palmitate have been synthesized from the cooking oil industry fatty acids. The reaction begins with esterification of palmitic acid with BF3 / methanol to produce a methyl palmitate ester with a yield of 72.13%. Furthermore, methyl palmitate ester was esterified using propylene glycol and K2CO3 as a base to produce 2-hydroxy propyl palmitate which acts as a bioaditive with a yield of 52.90%. Structure identification is done by Gas Chromatography-Mass Spectroscopy (GC-MS) method.