Preparation of carbon molecular sieves from carbon micro and nanofibers for sequestration of CO sub(2)

• Published in: Chemical engineering research & design Vol. 89; no. 9; pp. 1737 - 1746
• Main Authors: Bikshapathi, Mekala, Sharma, Ashish, Sharma, Ashutosh, Verma, Nishith
• Format: Journal Article
• Language: English
• Published: 01.09.2011
• Subjects: Carbon; Carbon dioxide; Devices; Heating; Microwaves; Molecular sieves; Nanofibers; Uptakes
• ISSN: 0263-8762
• DOI: 10.1016/j.cherd.2010.09.009

In this study, a hierarchal web of carbon micro and nanofibers was used as a precursor for the synthesis of a carbon molecular sieve (CMS). CMSs were prepared by thermal treatment of carbon fibers using a microwave heating device. The heating power and treatment time were optimized for the maximum performance of the prepared CMS for the separation of CO sub(2) at low concentrations from the gaseous mixture of CO sub(2) and air under dynamic (flow) conditions. Based on the experimental data, microwave power input of 240 W and treatment time of 15 min were found to be suitable for the maximum uptake of CO sub(2) by CMS. Adsorption breakthrough curves were obtained at different gas flow rates and CO sub(2) concentrations. CMSs prepared from the hierarchal web of carbon micro and nanofibers were found to be superior to those prepared from ACF. The CO sub(2) uptake was determined to be approximately 0.88 mg/g and 10 mg/g at concentrations of 500 ppm and 5000 ppm, respectively, in air.