Development of palm-based neopentyl glycol diester for transformer oil application

Transformer oil plays an important role as electrical insulator of transformers. Mineral-based transformer oil has relatively high toxicity, low biodegradability and low fire point. The use of vegetable oils has constraints because the presence of beta-hydrogen in its structure renders it susceptibi...

Full description

Bibliographic Details
Main Author: Abdul Raof, Nurliyana
Format: Thesis
Language:English
Published: 2015
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/68207/1/ITMA%202015%2011%20IR.pdf
_version_ 1796978672627875840
author Abdul Raof, Nurliyana
author_facet Abdul Raof, Nurliyana
author_sort Abdul Raof, Nurliyana
collection UPM
description Transformer oil plays an important role as electrical insulator of transformers. Mineral-based transformer oil has relatively high toxicity, low biodegradability and low fire point. The use of vegetable oils has constraints because the presence of beta-hydrogen in its structure renders it susceptibility to oxidation. The polyol esters have a unique feature that can overcome the oxidation problem faced by the vegetable oils. Hence the focus of this project is to study the potential of neopentyl glycol (NPG) diesters to be used as transformer oil. The synthesis of NPG diester was successfully optimized via transesterification of palm oil methyl ester (PME) with neopentyl glycol. The present study investigated the application of low-pressure technology as a new synthesis method which is able to shorten the reaction time. The optimum reaction conditions obtained by manual and response surface methodology (RSM) optimization were molar ratio of 2:1.3, reaction time of 1 hour, temperature at 182°C, pressure at 0.6 mbar and catalyst concentration of 1.2 wt%. The ester exhibited better properties than the commercial transformer oil especially with regards to the breakdown voltage, flash point and moisture content. The synthesized NPG diester was then formulated with anti-oxidant and pour point depressant to enhance its oxidative stability and low temperature properties. While 2,6-di-tert-butyl-p-cresol (DBPC) has proven to be useful and effective anti-oxidant for mineral oil, present studies indicate that it is not suitable to be used as additive in NPG diester, or in polyol ester as general. The pour point depressant on the other hand, has successfully increased the pour point of NPG diester from -14°C to -48°C. The laboratory thermal aging studies have also been developed to study the effect of temperature and aging time on selected properties and were compared with commercial mineral and refined, bleached and deodorized palm oil (RBDPO) at 90°C, 110°C and 130°C. It was found that aging has profound effect on the moisture content and acidity of the oil due to degradation of both oil and insulating paper. The result indicated that throughout the aging period, NPG diester exhibits low acid value and no significant changes to viscosity and breakdown voltage. The study on tensile properties of insulating paper aged in NPG diester at 130°C shows higher tensile strength than paper aged in mineral oil and RBDPO. The aging rate calculated based on tensile strength indicated that at high temperature, insulating paper degraded faster in mineral oil and RBDPO than in NPG diester. The synthesized NPG diester has high potential to be used as transformer oil.
first_indexed 2024-03-06T09:57:56Z
format Thesis
id upm.eprints-68207
institution Universiti Putra Malaysia
language English
last_indexed 2024-03-06T09:57:56Z
publishDate 2015
record_format dspace
spelling upm.eprints-682072019-05-10T01:50:50Z http://psasir.upm.edu.my/id/eprint/68207/ Development of palm-based neopentyl glycol diester for transformer oil application Abdul Raof, Nurliyana Transformer oil plays an important role as electrical insulator of transformers. Mineral-based transformer oil has relatively high toxicity, low biodegradability and low fire point. The use of vegetable oils has constraints because the presence of beta-hydrogen in its structure renders it susceptibility to oxidation. The polyol esters have a unique feature that can overcome the oxidation problem faced by the vegetable oils. Hence the focus of this project is to study the potential of neopentyl glycol (NPG) diesters to be used as transformer oil. The synthesis of NPG diester was successfully optimized via transesterification of palm oil methyl ester (PME) with neopentyl glycol. The present study investigated the application of low-pressure technology as a new synthesis method which is able to shorten the reaction time. The optimum reaction conditions obtained by manual and response surface methodology (RSM) optimization were molar ratio of 2:1.3, reaction time of 1 hour, temperature at 182°C, pressure at 0.6 mbar and catalyst concentration of 1.2 wt%. The ester exhibited better properties than the commercial transformer oil especially with regards to the breakdown voltage, flash point and moisture content. The synthesized NPG diester was then formulated with anti-oxidant and pour point depressant to enhance its oxidative stability and low temperature properties. While 2,6-di-tert-butyl-p-cresol (DBPC) has proven to be useful and effective anti-oxidant for mineral oil, present studies indicate that it is not suitable to be used as additive in NPG diester, or in polyol ester as general. The pour point depressant on the other hand, has successfully increased the pour point of NPG diester from -14°C to -48°C. The laboratory thermal aging studies have also been developed to study the effect of temperature and aging time on selected properties and were compared with commercial mineral and refined, bleached and deodorized palm oil (RBDPO) at 90°C, 110°C and 130°C. It was found that aging has profound effect on the moisture content and acidity of the oil due to degradation of both oil and insulating paper. The result indicated that throughout the aging period, NPG diester exhibits low acid value and no significant changes to viscosity and breakdown voltage. The study on tensile properties of insulating paper aged in NPG diester at 130°C shows higher tensile strength than paper aged in mineral oil and RBDPO. The aging rate calculated based on tensile strength indicated that at high temperature, insulating paper degraded faster in mineral oil and RBDPO than in NPG diester. The synthesized NPG diester has high potential to be used as transformer oil. 2015-12 Thesis NonPeerReviewed text en http://psasir.upm.edu.my/id/eprint/68207/1/ITMA%202015%2011%20IR.pdf Abdul Raof, Nurliyana (2015) Development of palm-based neopentyl glycol diester for transformer oil application. Masters thesis, Universiti Putra Malaysia. Electric insulators and insulation - Oils Oil palm
spellingShingle Electric insulators and insulation - Oils
Oil palm
Abdul Raof, Nurliyana
Development of palm-based neopentyl glycol diester for transformer oil application
title Development of palm-based neopentyl glycol diester for transformer oil application
title_full Development of palm-based neopentyl glycol diester for transformer oil application
title_fullStr Development of palm-based neopentyl glycol diester for transformer oil application
title_full_unstemmed Development of palm-based neopentyl glycol diester for transformer oil application
title_short Development of palm-based neopentyl glycol diester for transformer oil application
title_sort development of palm based neopentyl glycol diester for transformer oil application
topic Electric insulators and insulation - Oils
Oil palm
url http://psasir.upm.edu.my/id/eprint/68207/1/ITMA%202015%2011%20IR.pdf
work_keys_str_mv AT abdulraofnurliyana developmentofpalmbasedneopentylglycoldiesterfortransformeroilapplication