Gases breakthrough adsorption on activated carbon of porous synthesized renewable material

Abstract

Acidic and alkaline gases are the types of pollutant which may give negative impact on human life as well as environment without proper treatment. It is important to ensure that these types of gases concentration in oil and gas industry are up to regulatory standard before it can be released to surrounding. Activated carbon is one of the most effective adsorbents used in hazardous environmental treatments and it is considered to be sustainable, environmentally friendly, economical and efficient making it a superior and the most commonly used in adsorption process compared to other adsorbents. The research is aimed to synthesize agro-based solid waste materials to activated carbon (AC) and to determine the breakthrough time adsorption isotherm of single poisoning gases on the AC. In this study, palm empty fruit bunch and palm kernel shell were selected as the raw materials to produce AC. Char was produced through carbonization process and then undergone chemical treatments [potassium hydroxide (KOH), iron (III) chloride hexahydrate (FECI3.6H2O) and zinc nitrate hexahydrate (Zn (NO3)2.6H2O)] followed by microwave treatment in order to produce three different AC. Effect of different gases on the sorbent performance for adsorption breakthrough study were investigated. Testing of the prepared samples was accomplished using adsorption column breakthrough experiment. The breakthrough time adsorption testing was performed at 100 mL/min flowrate for 3.6 g of sample. The samples were characterized by thermo-gravimetric analysis, scanning electron microscope, Fourier transform infrared and nitrogen adsorption isotherm. Nitrogen adsorption isotherm results showed that the commercial activated carbon, palm kernel activated carbon treated with KOH-Zn (PKAC-KOH-Zn), palm kernel activated carbon treated with KOHFeCI3 (PKAC-KOH-FeCI3) and palm empty fruit bunch activated carbon treated with KOH (EFBAC-KOH) have Brunauer-Emmett-Teller surface area of 1,005.87, 259.17, 122.61 and 3.48 m2/g, respectively. For adsorption breakthrough study, the longer breakthrough time for acidic and alkaline gas adsorption implied better adsorption breakthrough performance. The end results showed that breakthrough times for three type of AC were not much different as compared to commercial AC. PKAC-KOH-FeCI3 was the best material for carbon monoxide and sulfur dioxide adsorption with 6.33 s and 51 s breakthrough time, respectively. PKAC-KOH-Zn produced the longest breakthrough time for chlorine adsorption of 1002.5 s and EFBAC-KOH produced the longest breakthrough time for ammonia adsorption of 175.67 s. As a conclusion, the findings revealed the potential of AC derived from palm kernel shell and palm empty fruit bunch as poisoning gases sorbents based on the good results obtained from characterization analysis and adsorption breakthrough study.