PALM OILAND METHYL OLEATE EPOXIDATION USING TBHP CATALYZED BY VANADIA/ SUPPORTED CATALYST
Countries in Europe are reducing the use of phthalates as plasticizers due to their toxic nature. Epoxidized palm oil can serve as an alternative plasticizer with non toxic and safe properties. Epoxidized palm oil (EPO) is synthesized by oxidizing triglyceride olefins using H202 and acid. However,...
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Format: | Theses |
Language: | Indonesia |
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Online Access: | https://digilib.itb.ac.id/gdl/view/75436 |
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Institution: | Institut Teknologi Bandung |
Language: | Indonesia |
Summary: | Countries in Europe are reducing the use of phthalates as plasticizers due to their toxic nature. Epoxidized palm oil can serve as an alternative plasticizer with non toxic and safe properties. Epoxidized palm oil (EPO) is synthesized by oxidizing triglyceride olefins using H202 and acid. However, thisprocess generates relatively difficult-to-control heat, corrosiveness, and can reduce epoxy selectivity due to further hydrolysis, causing the opening of the epoxy ring. The oxidation reaction of palm oil in this study utilizes tertiary-butyl hydrogen pe roxide (TBHP) as an oxidizing agent, catalyzed by vanadium that assisted by supported materials such as y -Al203, Ti02, Si02, Zr02, MIL-J OO(Fe), Ui0-66, MOF-808. Catalyst supports are chosen because vanadia can be deposited and facilitate catalyst regeneration. Regenerating V20s from palm oil is relatively challenging. Deposition of ViOs on various support materials is accomplished by impregnating alumina dropwise with a VO(acac)2 complex solution, followed by heating at J OO °C (2 hours) and calcination at 500 °C (5 hours). Catalytic reaction tests are also conducted with various types offirst-row transition metal oxides ( Cr20s, Mn02, Fe203, CuO, CoO, NiO), impregnated on y -A/203 support materials to evaluate their characteristics. Observations indicate excellent epoxidation on V20s/y -Al203 and ViOsffi02 compared to other oxides. Optimized reaction conditions are achieved at a temperature of 80 °C, 7 hours, 0.5 mo/% vanadium to olefin, and 3.5 meq. TBHP. Prolonged reaction times lead to epoxy ring opening. Kinetic studies of palm oil epoxidation by V20sly -Al203 show pseudo -second-order kinetics, while the V20s/Ii02 reaction exhibits pseudo-first-order kinetics with respect to palm oil. The results of the epoxidation reaction of palm oil catalyzed by V20sly-A fa 03 and V20s/Ii 02 respectively showed an activation energy (Ea) values: 27 kJ·moL-1 and 21 kJ·mol-1 a turnover number (TON) are 138 and 114, and a turnoverfrequency
( TOF) are 20 h-1 and 16 h-1
values of Gibbsfree energy (LJC;/ ) are 90 kl·mol-1 and
87 kl·mol -, entropy (LJSI) values are -188 J·mol -1-K-1 and -216 J·mol-1.K-, and
enthalpy (L1JII) values are 24 kJ·mol -1 and 18 kJ·mol -1
This activation energy is
lower than that reported fo r the uncatalyzed reaction (Ea of 127 kl·mol-1). The regeneration of V20sly -A fa0 3 catalyst is carried out using ethanol and drying at 80 °C (J hour). The epoxide y ield with the regenerated catalyst is relatively good, reaching up to 75%. The turnover number (TON) and turnoverfrequency ( TOF) of
V20s/l'i02 for palm oil epoxidation are lower, at 114 and 16 h-1
respectively,
compared to V20sly -Al 203 due to the lower surface area of the support catalyst. The methy l oleic epoxidation reaction catalyzed by V20sly-Al203 gave a yield of 65% at a relatively low temperature of 50 °C for 5 hours and the kinetics of the methyl oleic epoxide reaction showed pseudo first order.
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