Malaysian Journal of Analytical Sciences Vol 21 No 1 (2017): 20 - 26

DOI: http://dx.doi.org/10.17576/mjas-2017-2101-03

 

 

 

DEEP EUTECTIC SOLVENT AS A MEDIA IN SWELLING AND DISSOLUTION OF OIL PALM TRUNK

 

(Pelarut Eutektik Sebagai Media dalam Pembengkakan dan Pelarutan Batang Kelapa Sawit)

 

Emilia Abdulmalek^1,2*, Syarilaida Zulkefli¹, Mohd. Basyaruddin Abdul Rahman^1,2

 

¹Department of Chemistry, Faculty of Science

²Enzyme and Microbial Technology Research, Faculty of Biotechnology and Biomolecular Science

Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia

 

*Corresponding author: emilia@upm.edu.my

 

 

Received: 17 August 2015; Accepted: 9 November 2016

 

 

Abstract

Pre-treatment is a crucial step in biomass processing prior to the hydrolysis or fermentation to bioethanol. Herein, the potential of deep eutectic solvent (DES) in the pretreatment of oil palm biomass were described. The mechanism of swelling and dissolution of oil palm trunk (OPT) was studied under optical microscopy. The OPT fibres were stirred and heated at 100 °C in choline chloride:glycerol (ChCl:Gly), choline chloride:ethylene glycol (ChCl:EG), ethylammonium chloride:glycerol (EAC:Gly) and ethylammonium chloride:ethylene glycol (EAC:EG) with 1:2 molar ratio each. All DESs tested had showed homogenous swelling and disintegration of small fragments interaction mode with OPT. There were more small fragments observed in EAC-based DES compared to ChCl-based DES. This finding supports the result for the percentage of dissolution where OPT in EAC-based DES recorded higher dissolution with 55% and 50% in EAC:EG and EAC:Gly respectively whereas ChCl-based DES recorded only 33% and 29% in ChCl:EG and ChCl:Gly, respectively. In ChCl-based DESs the fragmentations were accompanied by large unswollen section of fibres. The formation of small fragments indicates that the fibres experienced a fast dissolution. Therefore, the EAC-based DESs proved to be a better swelling and dissolution media for oil palm biomass pretreatment compared to ChCl-based DES.

 

Keywords:  deep eutectic solvent, oil palm biomass, dissolution, swelling, pre-treatment

 

Abstrak

Pra-rawat adalah satu langkah dalam pemprosesan biomas sebelum hidrolisis atau fermentasi kepada bioetanol. Disini, potensi pelarut eutektik (DES) dalam pra-rawat biomas kelapa sawit telah diterangkan. Mekanisma pembengkakan dan pemelarutan batang kelapa sawit (OPT) telah dikaji dengan mikroskop optik. Fiber OPT telah dikacau dan dipanaskan pada suhu 100 ºC dalam kolin klorida:gliserol (ChCl:Gly), kolin klorida:etilin glikol (ChCl:EG), etilammonium klorida: gliserol (EAC:Gly) dan etilammonium klorida: etilin glikol (EAC:EG) dengan kadar molar 1:2 setiap satu. Semua DES yang dikaji telah menunjukkan mod interaksi pembengkakan secara setara dan pecahan fragmen kecil dengan OPT. Lebih banyak fragmen kecil dapat dilihat dalam DES berasaskan EAC berbanding dengan DES berasaskan ChCl. Ini disokong oleh peratusan pelarutan dimana OPT dalam DES berasaskan EAC menunjukkan keputusan lebih tinggi dengan masing – masing 55% dan 50% dalam EAC:EG and EAC:Gly sementara DES berasaskan ChCl hanya menunjukkan masing – masing 33% dan 29% dalam ChCl:EG dan ChCl:Gly. Bagi DES berasaskan ChCl, fragmentasi adalah disertai dengan kehadiran fiber besar yang tiada pembengkakan. Pembentukkan fragmen kecil menunjukkan bahawa fiber mengalami pelarutan yang cepat. Oleh itu, DES berasaskan EAC terbukti lebih baik sebagai media pembengkakan dan pelarutan bagi OPT berbanding DES berasaskan ChCl.

 

Kata kunci:  pelarut eutektik, biomas kelapa sawit, pelarutan, pembengkakan, prarawat

 

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