Characterization and catalytic activity of os/bentonite catalyst for hydrogenolysis of glycerol = Pencirian dan aktiviti pemangkin os/bentonit untuk tindak balas hidrogenolisis gliserol
In this study, osmium catalysts (Os/Bentonite, Os/TiO2 ) and ruthenium catalysts (Ru/Bentonite, Ru/TiO2 ) with 5% wt/wt metal loading were prepared using impregnation method and applied to convert glycerol, a renewable feedstock, to value-added chemical, 1,2-propanediol. Among these catalysts, t...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English English |
| Published: |
Malaysian Society of Analytical Sciences
2019
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/79230/ http://irep.iium.edu.my/79230/ http://irep.iium.edu.my/79230/ http://irep.iium.edu.my/79230/1/79230_Characterization%20and%20catalytic%20activity%20of%20os.pdf http://irep.iium.edu.my/79230/2/79230_Characterization%20and%20catalytic%20activity%20of%20os_SCOPUS.pdf |
| Summary: | In this study, osmium catalysts (Os/Bentonite, Os/TiO2
) and ruthenium catalysts (Ru/Bentonite, Ru/TiO2
) with 5% wt/wt metal
loading were prepared using impregnation method and applied to convert glycerol, a renewable feedstock, to value-added
chemical, 1,2-propanediol. Among these catalysts, the bentonite supported Os catalyst showed high performance with conversion
and selectivity to 1,2-propanediol which were 63.3% and 82.7%, respectively. Catalytic performances of these catalysts were
evaluated in glycerol hydrogenolysis using stainless steel autoclave reactor equipped with a magnetic stirrer at 150 C, hydrogen
pressure 20 - 40 bar for 7 hours reaction. The effect of glycerol concentration and reaction temperature were investigated to
obtain optimum conditions due to glycerol conversion and products selectivity greatly depend on these factors. Experimental
results show that hydrogenolysis of glycerol at 160 C reaction temperature and 5% glycerol concentration gives a conversion of
glycerol up to 100.0% with 82.9% selectivity of 1,2-propandiol. This study showed that bentonite which is cheap and abundant
clay is potentially a good catalyst support material. The Os/bentonite catalyst was characterized by Temperature Programmed
Reduction (TPR), nitrogen adsorption-desorption analysis (BET), Temperature Programmed Desorption-Ammonia(TPD-NH3
)
for obtaining some physicochemical properties of the catalysts.
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Dalam kajian ini, pemangkin osmium (Os/bentonit, Os/TiO2
) dan pemangkin ruthenium (Ru/bentonite, Ru/TiO2
) dengan muatan
logam 5% wt/wt disediakan dengan menggunakan kaedah impregnasi dan diaplikasikan kepada penukaran gliserol yang
merupakan bahan mentah yang boleh diperbaharui kepada bahan kimia yang bernilai tinggi iaitu 1,2-propanadiol. Antara
pemangkin yang dikaji, Os berpenyokong bentonit menunjukkan sifat pemangkin yang baik dengan nilai peratus penukaran dan
pemilihan masing-masing adalah 63.3% dan 82.7%. Aktiviti pemangkin diuji dalam tindak balas hidrogenolisi gliserol
menggunakan reaktor autoklaf tahan karat yang dilengkapi dengan pengacau magnetik pada suhu 150 ⁰C, tekanan hidrogen 20-
40 bar selama 7 jam. Kesan kepekatan gliserol dan suhu tindak balas didapati memberi kesan signifikasi terhadap peratus
penukaran gliserol dan pemilihan produk. Keputusan kajian menunjukkan bahawa keadaan optimum pada suhu 160 ⁰C dan
kepekatan gliserol 5% (wt/wt) memberikan penukaran gliserol sehingga 90.0% dengan peratus pemilihan terhadap 1,2-
propanadiol 82.9%. Kajian ini menunjukkan bahawa bentonit yang merupakan tanah liat murah dan mudah didapati adalah
berpotensi digunakan sebagai penyokong mangkin. Pemangkin Os/bentonit dicirikan menggunakan suhu pemprograman penurunan (TPR), analisis jerapan-nyahjerapan nitrogen (BET), suhu pemprograman nyahjerapan ammonia (TPD-NH3) bagi
mendapatkan maklumat mengenai sifat fizikal dan kimia pemangkin. |
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