Recycling of tobacco wastes in the development of ultra-high surface area activated carbon

Abstract

Activated carbons are vital for remediation processes such as water treatment. Nevertheless, some commercial versions have poor characteristics, such as low surface area and efficacy in removing contaminants. This work accessed the production of highly developed surface area activated carbons for environmental purposes and the recycling of tobacco wastes as an alternative precursor. Important parameters were tested, such as activation temperature (700, 800, and 900 °C) and mass ratio of chemical agents (KOH and ZnCl2, 3:1, 4:1, and 5:1 m:m). Activated carbons were evaluated using mathematical models of nitrogen adsorption and desorption isotherms (BET and BJH) and infrared spectroscopy (FT-IR). KOH was more effective than ZnCl2 as a chemical modifier, resulting in products with a greater surface area. Activation with KOH at 900 °C and a mass ratio of 4:1 resulted in a surface area of 3294 m2 g −1 and functional groups OH, CH, CO, CC, and CO, i.e., resulting in a promising adsorbent for contaminant sorption/removal processes. The developed methodology results in tobacco-based activated carbon with an extremely high surface area. Thus, tobacco wastes are excellent alternatives for producing KOH-activated carbons, besides being an ecological alternative to tobacco wastes destination.