Sains Malaysiana 39(5)(2010): 811–816

Selective Glycerol Esterification Over Organomontmorillonite Catalysts

(Pengesteran Gliserol Terpilih Menggunakan Pemangkin Organomontmorilonit)

Tri Yogo Wibowo

Pusat Teknologi Agroindustri

Badan Pengkajian dan Penerapan Teknologi

Jl. MH. Thamrin 8 Jakarta Pusat 10340 – Indonesia

Ridzuan Zakaria & Ahmad Zuhairi Abdullah*

Pusat Pengajian Kejuruteraan Kimia

Kampus Kejuruteraan, Universiti Sains Malaysia

14300 Nibong Tebal, Pulau Pinang, Malaysia

Diserahkan: 14 April 2000 / Diterima: 27 July 2009

ABSTRACT

Organomontmorillonites were synthesized by grafting cationic surfactants i.e quaternary ammonium compounds into the interlayer space and were characterized using XRD, FTIR and N2 adsorption/ desorption analysis. The organomontmorillonites were applied as catalyst for the esterification of glycerol (GL) with lauric acid (LA). The catalyst which had symmetrical onium salts (tetrabuthylammoniumbromide, TBAB) gave higher activity than that of unsymmetrical onium salts (cetyltrimethylammoniumbromide, CTAB). Over the TBAB-montmorillonite catalyst, glycerol monolaurate was obtained with a selectivity of about 80%, a lauric acid conversion of about 71% and a glycerol monolaurate yield of about 57%.

Keywords: Esterification; lauric acid; monoglyceride; montmorillonite; reaction

ABSTRAK

Organomontmorilonit telah disintesis melalui percantuman surfaktan kation iaitu sebatian ammonia kuartener kepada ruang lapisan-antara dan dicirikan menggunakan analisis XRD, FTIR dan jerapan/penyahjerapan N2. Organomontmorilonit ini telah digunakan sebagai mangkin bagi pengesteran gliserol (GL) dengan asid laurik (LA). Pemangkin yang mempunyai garam onium simetri (tetrabutilammoniumbromida, TBAB) memberikan aktiviti yang lebih tinggi berbanding pemangkin yang mempunyai garam onium tak simetri (setiltrimetilammoniumbromida, CTAB). Melalui pemangkin TBAB-montmorillonite, gliserol monolaurat telah diperolehi dengan pemilihan sebanyak 80%, penukaran asid laurik sekitar 71% dan hasilan gliserol monolaurat sekitar 57%.

Kata kunci: Asid laurik; monogliserida; montmorilonit; pengesteran; tindak balas

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*Pengarang untuk surat-menyurat; e-mail: chzuhairi@eng.usm.my