Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol

Authors

Mohammad Nasikin, Program Studi Teknik Kimia, Departemen Teknik Gas dan Petrokimia, Fakultas Teknik, Universitas Indonesia, Depok 16424, IndonesiaFollow

Abstract

Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol. Synthesize of methylamine from methanol and ammonia was studied in this research work using a partially potassium heteropoly salt (K3-xHxPW12O40 abbreviated as KPW) as a catalyst. KPW was prepared from heteropoly salt and potassium carbonate by using ion exchange method. The reaction was conducted at 600 ~ 800K and at the atmospheric pressure. Reactor used was a continue flow reactor with W/F=0,1~0,9g-kat.mnt./cc.Concentration of reactants and products were analyzed by gas chromathography while catalyst structure was observed by XRD (X-ray diffraction). Isothermal adsorption method was used for determining catalyst pore size. The result showed that ion exchange between H ion in zeolit with K ion produced potassium heteropoly salt that caused the change of interstitial space. The change of interstitial space was observed by the change of the lattice constant of the catalyst crystal. Trimethylamine(TMA) has molecule size smaller than catalyst pore size but bigger than molecular size of Dimethylamine (DMA) and Monimethylamine (MMA). This phenomenon caused the suppression of TMA formation. KPW has a rigid crystal structure and stabil during reaction. On the other hand, crystal structure of a non selective catalyst (NH4)3PW12O40 was not rigid and its pore size is easy to change depending on the product molecule size.

Bahasa Abstract

Metilamina yang disintesis dari metanol dan amoniak diteliti pada studi ini menggunakan katalis garam parsial kalium heteropoli (Cs3-xHxPW12O40 disingkat KPW). KPW dipreparasi dari asam heteropoli dan kalium karbonat dengan metode pertukaran ion. Reaksi dilakukan pada 600~800K dan tekanan atmosfir menggunakan reaktor alir kontinyu pada W/F=0,1~0,9g-kat.mnt./cc. Analisis konsentrasi produk dan reaktan menggunakan gas kromatografi sedangkan karakterisasi struktur katalis menggunakan XRD (X-ray diffraction) dan adsorbsi isothermal untuk menentukan ukuran pori katalis Hasil penelitian menunjukkan bahwa pertukaran ion H dengan K untuk membentuk garam kalium heteropoli menyebabkan perubahan interstisial space yang teramati dengan berubahnya lattice constant dari kristal katalis. Ukuran pori yang lebih kecil dari Trimetilamina (TMA) akan tetapi lebih besar dari Monometilamina (MMA) dan Dimetilamina (DMA) menyebabkan TMA menjadi tidak diproduksi. Kristal KPW bersifat rigid sehingga pori yang terbentuk tidak berubah sepanjang reaksi, sebaliknya kristal (NH4)3PW12O40 tidak rigid dan ukuran pori mudah berubah tergantung dari ukuran metilamina yang teradsorbsi sehingga katalis ini menjadi tidak selektif terhadap metilamina yang berukuran kecil.

References

1. Encyclopedia of Chemical Reaction Process, Vol.3, John Wiley and Sons Inc., New York, 1977, p.148
2. M. Fukatsu, Zeolite 5 (1993)16
3. I. Mochida, A. Yasutake, K. Takeshita, J. Catal. 82 (1998)313
4. K. Segawa, H. Tachibana, J. Catal. 131 (1991) 482
5. M. Nasikin, R. Nakamura, H. Niiyama, J. Jpn Petrol. Inst. 12 (1999) 369
6. M. Nasikin, Prosiding Seminar Nasional Fundamental dan Aplikasi Teknik Kimia, Surabaya, Indonesia, 2001, KR-03
7. S. Tatematsu, E. Echigoya. Chem. Lett. 3 (1984) 865.

Recommended Citation

Nasikin, Mohammad (2003) "Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol," Makara Journal of Technology: Vol. 7: Iss. 3, Article 3.
DOI: 10.7454/mst.v7i3.198
Available at: https://scholarhub.ui.ac.id/mjt/vol7/iss3/3