Effect of acid pretreatment of cocoa pod husk on its characterization of derived activated carbon

• Main Authors: Lin, Yu-Quan, 林育全
• Other Authors: Li, Po-min
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/n7rvrr

碩士 === 國立屏東科技大學 === 生物機電工程系所 === 106 === In order to enhance adsorption capacity of activated carbon (AC) from cocoa pod husk (CPH), CPH was first leached by acid and then used as a precursor (CPH-A) for preparing ACs by physical activation at activation temperature of 650-900℃ and holding time of 0-120 min in this work. Based on the proximate analysis, mineral compositions, thermogravimetric analysis and thermochemical properties, the differences between CPH and CPH-A were investigated. The chemical and pore properties of the resulting ACs were further studied. The results showed that the pre-treatment of CPH with hydrochloric acid led to removal of over 90% of the ash content in the CPH, mainly composed of potassium minerals. The Brunauer-Emmet-Teller (BET) surface area of the AC derived from CPH-A at 650℃ is 355.8 m2/g (AC-CPH-A-650), significantly larger than that (i.e., 1.1 m2/g) of the AC derived from CPH (AC-CPH-650). The higher activation temperature (e.g., 900℃) and longer holding time are beneficial to the pore development of the resulting AC, but have relatively low yields. The maximal BET surface area reached 1,464 m2/g for AC-CPH-A-900-120. As compared to commercial AC, the resulting AC indicated better equilibrium adsorption capacities under various initial methylene blue concentrations.