Sains Malaysiana 44(5)(2015): 747–752

Hydrogen Adsorption Capacity Reduction of Activated Carbon Produced from Indonesia Low Rank Coal by Pelletizing

(Pengurangan Kapasiti Penjerapan Hidrogen Karbon Aktifan melalui Pelet Dihasilkan

daripada Arang Batu Kelas Rendah Indonesia)

SRI HARJANTO¹*, LATIFA N. NOVIANA¹, MIA DINIATI¹, STEFANNO W. YUNIOR¹ & NASRUDDIN²

¹Department of Metallurgy and Materials Engineering, Universitas Indonesia

Kampus UI, Depok, 16424, Indonesia

²Department of Mechanical Engineering,Universitas Indonesia

Kampus UI, Depok, 16424, Indonesia

Diserahkan: 16 April 2014/Diterima: 22 Januari 2015

ABSTRACT

Coal-based activated carbon materials is a prospective materials for hydrogen storage application. The present work aimed to study the effect of post treatments including mechanical milling process and pelletization and simulating experimentally the conditions of pelletization of fine particles of activated coal. Post treatment of activated coal consist of 2 steps mechanical milling process in planetary ball mill followed by pelletization. First step of mechanical milling process gave particle size reduction and second step was undertaken to maintain activity of activated coal. Second step of mechanochemical process were done in dry (ACP-A) and wet condition (ACP-B) with the ratio of sample: KOH was 1:1 and performed for 1 h. Then they will be formed into pellets with the addition of binder which contained fructose, glucose and oligo. Some examinations such as PSA, BET, SEM and XRD were performed to determine the characteristics of activated carbon materials including hydrogen adsorption capacity testing. Particle size reduction of activated carbon reached 98.9% after planetary ball milling. The raw material of activated carbon (AC) has hydrogen adsorption as much as from 0.30 and 0.25 wt. % from -5 and 25oC measurements, respectively. As predicted the adsorption of hydrogen gas of pelletized activated carbon from bituminous coal decreased due to post treatment process about 47% for ACP-A and 60% for ACP-B at 4000 Bar.

Keywords: Activated coal; bituminous coal; hydrogen adsorption; pelletizing; planetary ball mill; volumetric adsorption

ABSTRAK

Bahan berasaskan arang batu karbon aktifan adalah bahan prospektif untuk penyimpanan hidrogen. Kertas ini bertujuan untuk mengkaji kesan selepas rawatan termasuk proses pengilangan mekanik dan membuat pelet serta mensimulasi uji kaji keadaan membuat pelet daripada zarah halus arang batu aktifan. Pasca rawatan arang batu aktifan terdiri daripada 2 langkah proses pengilangan mekanik di kilang planet bebola diikuti dengan membuat pelet. Langkah pertama proses pengilangan mekanik ialah mengurangkan saiz zarah dan langkah kedua diambil untuk mengekalkan aktiviti arang batu aktifan. Langkah kedua proses kimia mekanik dijalankan dalam keadaan kering (ACP-A) dan basah (ACP-B) dengan nisbah sampel: KOH ialah 1:1 selama 1 jam. Kemudian mereka akan dibentuk menjadi pelet dengan pengikat yang mengandungi fruktosa, glukosa dan oligo. Beberapa ujian seperti PSA, BET, SEM dan XRD telah dijalankan untuk menentukan ciri bahan karbon aktifan termasuk ujian kapasiti penjerapan hidrogen. Pengurangan saiz partikel karbon aktifan mencapai 98.9% selepas pengisaran planet bebola. Bahan mentah karbon aktifan (AC) mempunyai pengukuran penjerapan hidrogen masing-masing sebanyak 0.30 dan 0.25 wt. % dari -5 dan 25oC. Seperti diramalkan penjerapan gas hidrogen daripada pembuatan pelet karbon aktifan daripada arang batu berbitumen menurun kerana proses pasca rawatan sebanyak 47% untuk ACP-A dan 60% untuk ACP-B pada 4000 Bar.

Kata kunci: Arang batu aktifan; arang batu berbitumen; membuat pelet; penjerapan hidrogen; pengisaran planet bebola; penjerapan isi padu metric

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*Pengarang untuk surat-menyurat; email: harjanto@metal.ui.ac.id