Sains Malaysiana 41(7)(2012): 885–892

Optimization of n-Hexane Reforming Using Taguchi Orthogonal Array Design

(Pengoptimunan Pembentukan Semula n-Heksana Menggunakan Reka Bentuk Taguchi

 Tatasusunan Ortogon)

Chandra Mohan Sinnathambi* & Reem Ahmed Mohammed Ismail

Department of Fundamental and Applied Science, Universiti Teknologi PETRONAS

Bandar Seri Iskandar, 31750 Tronoh, Perak, Malaysia

Received: 16 August 2011 / Accepted: 30 January 2012

ABSTRACT

Taguchi orthogonal array design, a statistical software is applied to n-hexane reforming. The purpose is to identify the most significant process variable in reforming conditions favouring n-hexane conversion to high aromatics and isomers and low cracked and coke precursor reformate products. Actual experimental data were used for this study. Three process variables i.e. temperature, contact time and hydrogen partial pressure were investigated. From the study it was found that the contact time was the most critical operating parameter for n-hexane conversion followed by reaction temperature and hydrogen partial pressure. It was also noted that enhanced n-hexane reforming conversion can be achieved by operating the process at reaction temperature 723 K and contact time 7.1 min with a H2 partial pressure 300 kPa. For selectivity to aromatics and isomers lower contact time of 1.07 min with intermediate hydrogen partial pressure of 300 to 500 kPa operating at a reaction temperature of 723 K is most favourable.

Keywords: Aromatic; coke; conversion; n-hexane reforming; selectivity

ABSTRAK

Reka bentuk Taguchi tatasusunan ortogon, satu perisian, statistik telah digunakan untuk pembentukan semula n-heksana. Tujuan utama adalah untuk mengenal pasti pemboleh ubah yang mementingkan proses pembentukan semula n-heksana bagi menghasilkan aromatik dan isomer yang tinggi pengeluarannya dan kurangkan produk retak dan kok. Data uji kaji telah digunakan untuk kajian ini. Tiga pemboleh ubah telah dikaji iaitu suhu, sentuhan masa dan separa tekanan hidrogen. Daripada kajian ini, didapati bahawa sentuhan masa adalah parameter yang paling penting dalam operasi penukaran n-heksana diikuti oleh suhu tindak balas dan separa tekanan hidrogen. Selain itu, penukaran pembentukan semula n-heksana boleh dipertingkatkan dengan menjalankan proses pada suhu 723 K, dengan sentuhan masa selama 7.1 min dan pada 300 kPa separa tekanan hidrogen. Untuk mementingkan penghasilan produk aromatik dan isomer, keadaan terbaik adalah apabila sentuhan masa ialah 1.07 min, separa tekanan hidrogen yang sederhana iaitu di antara 300 kPa sehingga 500 kPa dan pada suhu 723 K.

Kata kunci: Aromatik; kok; operasi penukaran; pembentukan semula n-heksana; penghasilan produk

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*Corresponding author; email: chandro@petronas.com.my