GREEN SINTESIS DAN UJI SIFAT FISIKOKIMIA ASETAL SIKLIK METIL 9,10–DIHIDROKSISTEARAT SEBAGAI BIOPELUMAS GREEN SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES TEST OF CYCLIC ACETAL METHYL 9,10– DIHYDROXYSTEARATE AS BIOLUBRICANT

Kurniawan, Yehezkiei, Tutik Dwi Wahyuningsih

2016 | Skripsi | FMIPA

The green synthesis and physicochemical properties test of cyclic acetal methyl 9.10-dihydroxystearate (ASMDHS) compound as biolubricant has been done. The aims of this research were to study esterification reaction between 9.10-dihydroxystearic acid (DHSA) and methanol with montmorillonite KSF and H2SO4 catalysts via reflux and sonochemistry method, to study acetalization reaction between methyl 9.10-dihydroxystearate (MDHS) and pentanal in the presence of montmorillonite KSF and pTSA as catalysts through reflux and sonochemistry method, and to know lubricant physicochemical properties like density, dinamic viscosity, kinematic viscosity, viscosity index, total acid number, total base number and iodine value. At the beginning, oleic acid was hydroxylated at 0-10 °C to gave DHSA, and then it was reacted with methanol to form MDHS. The ASMDHS compound was obtained from reaction between MDHS and pentanal. The structure of each products were identified by FTIR and GC-MS. Hydroxylation reaction of oleic acid gave white solid of DHSA with melting point 131.1-131.8 °C in 46.52% yield. Esterification reaction of DHSA with methanol gave MDHS as white solid, where the best results were obtained with H2SO4 catalyst through reflux and sonochemistry method in 93.94 and 87.88% yield. Acetalization reaction of MDHS with pentanal gave yellow viscous liquid of ASMDHS, where the best results were obtained with montmorillonite KSF catalyst through reflux and sonochemistry method in 79.15 and 85.43% yield. The ASMDHS compound has density of 0.926 g/mL, dinamic viscosity at 40 and 100 °C of 161.96 and 16.36 cP, viscosity index of 107.70, total acid number of 59.8 mg KOH/g, total base number of 8.26 mg KOH/g and iodine value of 0.13 mg I2/g.

Kata Kunci : Penelitian mengenai pengenalan ekspresi matematika terus mengalami perkembangan, seiring berkembangnya peralatan interaksi dengan manusia dan bertambahnya minat dalam menyalin dokumen ilmiah ke dalam bentuk elektronik. Proses pengenalan ekspresi matema