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"In this paper, we perform combination methods of semi-empirical research, a theoretical approach, and force-matching to determine the optimum adsorption capacity on an open-ended single-walled carbon nanotube (SWCNT) as a diameter function. Using a semi-empirical study, we can determine the value of monolayer coverage and isosteric heat of adsorption from available thermodynamic data. By completing the semi-empirical study, we carried out quantum mechanical calculations to determine the adsorption energy on the interior and exterior of SWCNTs. Furthermore, monolayer coverage, specific surface area, and maximum adsorption capacity as the main quantity in the adsorption process was estimated using the combination method of force-matching and a classical Lennard-Jones potential model. Hydrogen physisorption was investigated on zig-zag SWCNTs at conditions for a pressure range of 0.1 to 10 MPa at 233 K and 298.15 K temperature. The adsorption of all data can be explained with the Toth model. The results shows the SWCNT exterior physisorption energy range between 1.35 to 1.62 kcal/mol. The interior range from 1.22 to 2.43 kcal/mol. With a wide degree of temperature and pressure variations, we obtained an optimum SWCNT diameter of 8-12 Å . At the optimum diameter maximum adsorption capacity, we achieved 1.75 wt% at 233 K and an operating pressure of 10 MPa."

"The investigation of adsorption isotherms is a prime factor in the ongoing development of adsorption cycles for a spectrum of advanced, thermally-driven engineering applications, including refrigeration, natural gas storage, and desalination processes. In this work, a novel semi-empirical mathematical model has been derived that significantly enhances the prediction of the steady state uptake in adsorbent surfaces. This model, a combination of classical Langmuir and a novel modern adsorption isotherm equation, allows for a higher degree of regression of both energetically homogenous and heterogeneous adsorbent surfaces compared to several isolated classical and modern isotherm models, and has the ability to regress isotherms for all six types under the IUPAC classification. Using a unified thermodynamic framework, a single asymmetrical energy distribution function (EDF) has also been proposed that directly relates the mathematical model to the adsorption isotherm types. This fits well with the statistical rate theory approach and offers mechanistic insights into adsorption isotherms."

"Oleic imidozaline is one of the nitrogen containing heterocyclic compounds that has been widely used as commercial corrosion inhibitor, especially in minizing the carbon dioxcide induced corrosion process in oilfield mining....."

"Adsorption Thermal Energy Storage (ATES) adalah metode penyimpanan energi termal berbasis adsorpsi yang digunakan untuk mengatasi ketidakseimbangan antara supplai dan permintaan energi pada waktu bersamaan. Tujuan dari penelitian ini untuk meningkatkan sistem adsorpsi agar menghasilkan energi yang lebih besar dan sistem yanglebih ekonomis. Disertasi ini menyajikan analisa dari sistem ATES dengan menggunakan adsorben alami berupa zeolit alam asli Indonesia. Pada penelitian ini juga dilakukan modifikasi zeolit alam dengan menggunakan larutan NaCl untuk memperoleh kapasitas adsorpsi yang lebih baik. Adsorben yang digunakan adalah zeolit alam asal Blitar dan air sebagai fluida kerjanya. Pengukuran dilakukan dengan beberapa variasi massa materialadsorben (NZE activated dan zeolit alam hasil modifikasi NaCl). Hasil penelitian menunjukkan bahwa adsorben zeolit alam yang dimodifikasi dengan menggunakan larutan NaCl terbukti meningkat luas permukaannya hingga 38.8% dengan struktur yang tetap stabil, memiliki area gugus H2O yang lebih luas serta mampu menghasilkan beda temperatur yang cukup tinggi yaitu rata-rata hingga 50oC pada saat proses adsorpsi.Energy Storage Density (ESD) untuk zeolit alam hasil modifikasi lebih besar dibandingkan zeolite alam sebelum modifikasi yaitu hingga 290.6 kWh/m3 dengan nilai efisiensi tertinggi yaitu 41%.

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Adsorption Thermal Energy Storage (ATES) is an adsorption-based thermal energy storage method used to address the imbalances between supply and demand of

energy. The purpose of this research is to improve the adsorption system in order to produce a greater energy and a more economical system. This dissertation presents an

assessment of natural zeolite from Blitar, Indonesia that is applied as an adsorbent in the ATES system. To obtain a better adsorption capacity, the natural zeolit was modified using NaCl solution and water as the working fluid. The measurements were made with several mass variations of the adsorbent material (pure natural zeolit and natural zeolit modified by NaCl). The results showed that the natural zeolit adsorbent modified using NaCl solution was shown to have increased surface area until 38.8% with a stable structure, had a wider H2O goup area, and was able to produce a quite high-temperatur difference, which is up to 50oC on average during the adsorption process. The value of Energy Storage Density (ESD) for modified natural zeolitis higher than pure natural zeolit, which is up to 290.6 kWh/m3. The highest efficiency value reaches 41%."