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Abstrak :
There is an abundant source of naturally occurring mordenitein the Bayah region of Indonesia. In this work we studied how acid dealumination of this indigenous zeolite affected its physical, chemical and catalytic properties. The results are compared to those obtained with another natural mordenite and a commercially available synthetic mordenite. Acid dealumination of mordenites is known to affect the pore structure and therefore enhance the adsorption-properties of the zeolite and the accessibility to its acidic sites. A series of dealuminated mordenite samples were prepared. They were refluxed in constant boiling HCl as a function of time. The samples were each subsequently exchanged with IN ammonium nitrate. The Si/Al ratio was determined by X-Ray Fluorescence. The presence of other metals was detected with Atomic Adsorption Spectroscopy and Inductively Coupled Plasma Spectroscopy. Nitrogen Adsorption was used to determine the surface area and the pore size distribution. Crystallinity and unit cell size were determined via X-Ray Diffraction. The surface morphology was probed with Scanning Electron Microscopy. An n-hexane cracking test was utilized to probe catalytic activity and selectivity. The results of this study indicate that up to and including sixteen hours of reflux, dealumination of this natural Indonesian mordenite increases the crystallinity and the average pore size, however the surface area and the unit cell size remain constant. Additional reflux, beyond sixteen hours, destroyed a portion 'of the zeolitic framework, indicated by a loss in crystallinity. Cracking activity increased through sixteen hours .of ref lux and was found to be constant thereafter. Total' C2, C3 and C4 {including isobutene) selectivity improved through sixteen hours of reflux and then also remained constant. In comparison to a commercially available sample of synthetic mordenite, the modified Indonesian mordenite ,is less active, but has comparable selectivity. However, compared to the naturally occuring U.S. mordenite, the modified Indonesian mordenite has improved physical and catalytic properties.

Abstrak :
Salah satu upaya ECBM adalah dengan menginjeksikan gas nitrogen ke dalam reservoir CBM. Gas nitrogen yang diinjeksikan ke dalam reservoir batubara tersebut teradsorp seiring dengan berkurangnya CH4 di dalam reservoir tersebut. Oleh sebab itu, diperlukan informasi mengenai karakteristik adsorpsi N2 pada batubara Indonesia, mengingat Indonesia memiliki potensi CBM yang cukup besar, yaitu 450 TCF. Dalam penelitian ini, digunakan sampel batubara Barito dan Ombilin sebagai adsorben. Kapasitas adsorpsi N2 pada batubara Indonesia diperoleh dengan adsorpsi tekanan tinggi dengan variasi kandungan air pada temperatur 25°C - 55°C dan tekanan 0 atm - 60 atm. Dari penelitian ini diperoleh bahwa kapasitas adorpsi N2 pada batubara Barito 6,85 % hingga 16,92 % lebih banyak daripada batubara Ombilin. Selain itu, peningkatan temperatur dapat menurunkan kapasitas adsorpsi hingga 8,96 %. Kandungan air pada batubara juga dapat menyebabkan penurunan kapasitas adsorpsi 11,6 % hingga 11,8 %. Data eksperimen yang direpresentasikan dengan model Ono-Kondo menghasilkan deviasi hingga 11,75 % AAD. ......Injecting high pressure nitrogen into CBM reservoir is one of ECBM methods. The nitrogen injected into CBM reservoir will be adsorbed on coal surface, while partial pressure of methane decreases. The consequences, we need information about nitrogen adsorption capacity on Indonesian coal, considering that Indonesia has 450 TCF CBM potential. Barito and Ombilin coal are used as adsorben. Nitrogen adsorption capacity obtained by doing high pressure adsorption using water content variation at temperature 25°C - 55°C and pressure 0 atm ' 60 atm. This experiments results that N2 adsorption capacity on Barito coal is 6,85 % - 16,92 % higher than Ombilin coal. Additionally, increasing temperature cause decreasing N2 adsorption capacity on coal as much as 8,96 %. Water content also decreases adsorption capacity as much as 11,6 % up to 11, 8%. This experiment data correlated using Ono-Kondo model results in deviation up to 11,75 % AAD.