The Malaysian Journal of Analytical Sciences Vol 17 No
1 (2013): 109 – 118
PENGEKSTRAKAN DAN PENCIRIAN NANOSELULOSA DARIPADA SERABUT KELAPA
(Extraction and Characterization of Nanocellulose from
Coconut Fiber)
Nor Liyana Ahmad
dan Ishak Ahmad*
Pusat Pengajian Sains Kimia dan Teknologi Makanan,
Fakulti Sains dan Teknologi,
University Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
*Corresponding author: gading@ukm.my
Abstrak
Pengubahsuaian
kimia telah dijalankan ke atas serabut kelapa untuk mengekstrak nanohablur
selulosa daripadanya. Antara rawatan yang dilakukan adalah rawatan alkali,
rawatan penambahan peluntur dan akhirnya hidrolisis menggunakan asid sulfurik
pekat. Kesan setiap rawatan kimia terhadap serabut kelapa dianalisa menggunakan
spektroskopi inframerah transformasi Fourrier (FTIR) dan analisis pembelauan
sinar-X (XRD). Seterusnya perubahan morfologi permukaan dikaji menggunakan
mikroskop imbasan elektron (SEM) manakala kestabilan terma gentian serabut
kelapa dikaji melalui analisis termogravimetrik (TGA). Hasil analisis
menunjukkan pengubahsuaian kimia yang dilakukan dapat menyingkirkan
hemiselulosa dan lignin daripada serabut kelapa. Analisis XRD juga telah
menunjukkan peningkatan kehabluran serabut selepas setiap peringkat rawatan.
Nanoselulosa yang terhasil daripada proses hidrolisis menggunakan asid sulfurik
dianalisis menggunakan mikroskop transmisi elektron (TEM) bagi mengenal pasti
saiz nanoselulosa yang diperoleh. Didapati purata diameter nanoselulosa
daripada serabut kelapa adalah 13.7 ± 6.2 nm manakala panjangnya adalah 172.34
± 8.4 nm. Selulosa nanohablur mempunyai pelbagai potensi dalam aplikasi seperti
bioperubatan, jerapan minyak, membran, farmasi dan biokomposit.
Kata kunci:
serabut kelapa, nanohablur
selulosa, lignin, hemiselulosa
Abstract
Coconut husk fibers has been modified by some chemical treatments to
extract cellulose nanocrystals (CNC), which are alkali treatment, bleaching and
acid hydrolysis using concentrated sulphuric acid. The effect of the treatments
on the coconut husk fibers has been analysed using Fourier transform infrared
(FTIR) and X-Ray diffraction (XRD). Meanwhile, the morphology observation and
thermal stability of the fiber have been analysed by scanning electron
microscopy (SEM) and thermogravimetric analysis (TGA) respectively. The
analyses show that the chemical modification could eliminate some of the lignin
and hemicelluloses of the fiber. Nanocellulose extracted from acid hydrolysis
has been analysed using transmission electron microscopy (TEM) to define the
size of extracted nanocellulose. The cellulose nanocrystals from coconut fibre
has the average diameter and length in the range 13.7 ± 6.2 nm and 172.3 ± 8.4
nm, respectively. The obtained nanocellulose may have the potential applications
in the fields of biomedical, oil adsorption, membrane, pharmaceutical and
biocomposites.
Keywords: Coconut husk fiber,
cellulose nanocrystals (CNC), lignin, hemicelluloses
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