INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 9, ISSUE 08, AUGUST 2020 ISSN 2277-8616 523 IJSTR©2020 www.ijstr.org H 2 S Dissociation In Natural Gasbecomes H 2 And S 8 By Zeolite And Caocomposite Synthesis Catalyst Rifqi Sufra, Muhammad Djoni Bustan, Sri Hartati Abstract: The petrochemical industry is predicted for the next few years to still use raw materials from fossil fuels such as natural gas. The natural gas used still contains H2S which is corrosive and has the risk of poisoning the catalyst so that the presence of H2S is avoided before it damages or degrades the performance of the catalyst as used in the steam reforming or steam converting process. Several studies aimed at recovering hydrogen and sulfur. One such effort is through a thermal dissociation process. To dissociate H2S into hydrogen gas and S2 gas, an operating temperature of 1300 o C is required. This method is less economical to apply to industry because it requires large amounts of energy and does not produce solid sulfur [9]. As a result researchers used catalysts to reduce energy consumption and also sought to convert into solid sulfur. From several studies by Nguyen et al, 2015 [8], zeolite modification with metal has the potential to increase H2S absorption in room temperature. It is hoped that the invention can be considered as an alternative ZnO catalyst. Therefore, in this study an attempt was made to make a catalyst made from natural zeolite combined with a metal compound, CaO. The catalyst preparation process is carried out by the impregnation method, in which there are 3 variations of the catalyst based on CaO : Natural Zeolite ratio that is, 1 : 5, 1 : 7.5, and 1 : 10. These three types of catalyst have been tested using SEM and XRD, where the results show success in the impregnation process. Furthermore, in this study a trial was carried out on the use of catalysts to absorb the gas that became the raw material. The mass of the catalyst in each variation of the composition used is also varied in mass, namely 40 gr, 50 gr, 60 gr, 70 gr, and 80 gr. In the process, variations in the feed flow rate of the catalyst are varied, namely 5, 10, 30, 50, and 80 Liters / minute. Therefore, it is known that the composition of CaO and Zeolite 1: 5 is the best composition and produces the highest conversion. The lower the flow rate and the higher the value of the catalyst mass, the better dissociation of H2S. Index Terms: Adsorbent, H2S, ZnO, Zeolite, CaO, Dissociation. ——————————  —————————— 1. INTRODUCTION However, the quality of Natural gas used as the raw material contains H2S which is corrosive and highly potential to be degrading the catalyst performance within the steam reforming or steam converting process. Thus, the H2S presence in the natural gas has to be removed before it was used as the raw material for production. The reaction mechanism is as follows: ZnO + H 2 S → ZnS + H 2 O In this process the sulfur contained in natural gas will be adsorbed on ZnO while H 2 O remained along with the natural gas. ZnO adsorbent which has been binding sulfur to ZnS cannot be regenerated so that it gradually experiences saturation, as a result the adsorbent must be replaced with new adsorbent every time saturation occurs. Sulfur bound to ZnO adsorbent will form ZnS which will become a waste, while this adsorption process also produce water that potentially reduced the partial pressure. Considering the adsorbent high cost due to the high consumption, also the potential of H 2 S was unable to be utilized in this process, it has led some researchers to find a more economical process. There are several studies aimed to recover hydrogen and sulfur, one of them is by a thermal dissociation process. To dissociate H 2 S into hydrogen gas and S 2 gas, an operating temperature of 1300 o C is required. This method is less economical to apply to industry because it requires large amounts of energy and does not produce solid sulfur [9]. As a result, some study used a catalyst in order to reduce the energy consumption while sought to convert them into solid sulfur. Zhakkarov et al (2004) [11] used cobalt sulfide catalysts to decompose H 2 S into hydrogen (H 2 ) and solid sulfur (S 8 ) at room temperature. In the results of his research it was mentioned that H 2 S can be dissociated to form solid sulfur through several stages of the reaction mechanism that takes place on the surface of the catalyst namely molecular adsorption, dissociative chemisorption, the release of hydrogen molecules and sulfur recombination. In this study, solid sulfur was successfully obtained, but the resulting H 2 S conversion was still quite low at 10-20%.Zhao et al. (2007) [12] dissociated H 2 S in corona pulsed discharge reactors with the help of electric power of 6.9-30 kV and with the addition of gas balances Ar, He, N 2 and H 2 . In his research, the results showed that the presence of gas balance affects H 2 S dissociation. The presence of argon gas can increase the maximum H 2 S dissociation conversion by 25%.Carried out the dissociation of H 2 S at 28 o C using an MgO metal oxide catalyst which took place in a fixed bed reactor [5]. In his research, the remaining undissociated H 2 S <0.6 ppm. Based on the development of these studies, it turns out that the process of H 2 S dissociation can take place at low temperatures if using a catalyst. Zeolite is a natural material that is very easy to find, and the price is also very affordable. Zeolites can be monetized through ion exchange with metals to increase the absorption capacity of H 2 S as shown in Table 1. [8]. TABLE 1 THE RESULTS OF THE ZEOLITE AND METAL COMBINATION FOR ABSORBING H 2 S Source: Nguyen et al. 2015[8].