PDF Publication Title:
Text from PDF Page: 001
International Journal of Chemical Engineering and Applications, Vol. 4, No. 5, October 2013 Effect of Process Condition in Plasma Electrolysis of Chloralkali Production Nelson Saksono, Fakhrian Abqari, Setijo Bismo, and Sutrasno Kartohardjono Abstract—Chlor-alkali is one of the most important processes in chemical industry. This process produces chlorine and caustic soda that becomes the main feedstock of daily needs products. In this study, the process condition on chlorine gas production by electrolysis plasma is examined. Plasma electrolysis can increase the chlorine gas production up to 24 times in single compartment reactor and can reach up to 59 times in double compartment reactor compared to electrolysis process. In reactor with single compartment, high voltage results high current then cause high-energy consumption. The highest chlorine gas production is at 0.5 M and 300 V that results 4.63 mmol within 15 minutes. On the other hand, using double compartment reactor, current is lower due to its higher distance between two electrodes that makes the higher resistance. In this case, the highest chlorine gas production is at 0.5 M NaCl and 700 V that results 11.25 mmol within 15 minutes. The use of ion selective membrane can keep the movement of charge from one electrode to other. Ion selective membrane can separate side product of NaOH, but side reaction of chlorine ion still exists. Index Terms—Plasma electrolysis, voltage, concentration, depth, distance, ion-selective membrane. I. INTRODUCTION Chlor-alkali industry is one of the most important industrial sectors in chemical industry. This sector supports other sectors because its products can be used as raw materials in other industry. In Europe, chlor-alkali industry supported about 55% of chemical and pharmaceutical industries which gave profits up to 660 billion in 2009 [1]. Chlor-alkali Industry produces chlorine, hydrogen, caustic soda (NaOH), hypochlorite, and other derivatives of chlorine from NaCl and water (H2O) as raw materials. Chlorine (Cl2) and caustic soda (NaOH) are two of ten chemical substances which are the most produced and used as raw materials of other daily products, such as: medicines, detergents, deodorants, plastics, herbicides, insecticides, disinfectants, etc. [2]. Chlor-alkali production needs much electrical energy to process the electrolysis of alkali solution (NaCl). The cost for electricity in industry can reach until 70% of the selling price of the products [3]. Therefore, the effort to reduce the consumption of electrical energy in this industrial sector is needed by doing research to get more efficient method and technology. Chlor-Alkali uses the electrolysis process to produce its products. Electrolysis is a method of compound’s bonding separation by passing the electric current. Ionic compound, Manuscript received July 29, 2013; revised September 30, 2013. The authors are with the Department of Chemical Engineering, Universitas Indonesia, Depok 16424, Indonesia (e-mail: nelson@che.ui.ac.id). NaCl, will be decomposed in the solvent and form ions in the solution. Positive discharge electrode is called anode and the negative one is cathode. Each electrode bonds ions which have different discharge, so that ions with negative discharge will go to anode and the positive ions will go to cathode. Nevertheless, electrolysis of NaCl solution (brine electrolysis) used in chlor-alkali production has significant weaknesses, those are low conversion resulted by the electrolysis process and the use of high electric current when the electrolysis process occur [4]. Hence, it is needed to observe other possible technologies that can be applied in the production of chlor-alkali to reduce the energy consumption. One of the technologies that can reduce the energy consumption is plasma electrolysis. The plasma electrolysis process is similar with electrolysis process, but it is done with high enough voltage until the electric spark is formed producing the plasma on the electrolyte solution. The plasma will produce reactive species such as radicals on large amount which are accelerated by the sharp potential gradient and have enough kinetic energy to induce unique chemical changes in aqueous solutions, so it is able to increase the formation of products in solution several more times than the Faraday electrolysis process [5], [6]. Using this technology may reduce the energy consumption several times than conventional electrolysis so the productivity is more effective [6]. II. METHOD The design of reactor is shown in Fig. 1. The reactor has two compartments where one compartment is equipped with graphite as anode and stainless steel as cathode in the other side. This reactor can also be modified as one compartment reactor by closing the connector between two compartments. The reactor is batch system made from acrylic housing filter connected with globe valve. The electric source is connected to 3-kVA-slide regulator with the output is then connected to 4x transformer. Diode Bridge is used to rectify the electric current. The current is measured and noted from ampere-meter Yuhua A830L. The reactor design is also fulfilled with chlorine and hydrogen gas measurement. The chlorine gas produced is passed into KI 2% solution and hydrogen gas is passed into hydrogen analyzer. KI bonded the chlorine gas and reacted to form iodine that results the orange color in KI solution. Then, the solution was titrated by Na2S2O3 0.01 N. This study analyzed the formation of plasma by varying NaCl concentration from 0.05 M to 0.5 M with voltage from 500 V – 700 V. Furthermore, it measured the chlorine gas produced and calculated the energy consumption of the process. DOI: 10.7763/IJCEA.2013.V4.308 266PDF Image | Plasma Electrolysis of Chloralkali Production
PDF Search Title:
Plasma Electrolysis of Chloralkali ProductionOriginal File Name Searched:
308-A687.pdfDIY PDF Search: Google It | Yahoo | Bing
Salgenx Redox Flow Battery Technology: Power up your energy storage game with Salgenx Salt Water Battery. With its advanced technology, the flow battery provides reliable, scalable, and sustainable energy storage for utility-scale projects. Upgrade to a Salgenx flow battery today and take control of your energy future.
CONTACT TEL: 608-238-6001 Email: greg@salgenx.com (Standard Web Page)