Biosorption of Heavy Metal Ions from Industrial Waste Water by Banana Peel Based Biosorbent

The main purpose of this project is to study the potential of using banana peel (BP) as biosorbent in removing heavy metal ions and oil/grease particles from industrial waste water. The study emphasizes on the parameters involved in the preparation phase of the BP adsorbent, such as particle sizes, activating agent, impregnation ratio, carbonization temperature and duration. The dried BP is first grinded into two different particle sizes (0.25mm and 3.00mm), then chemically activated using either zinc chloride or phosphoric acid and carbonized at different sets of temperature and duration into activated carbon, which is a popular type of adsorbent used in industrial waste water treatment. The characterization of BP based activated carbon is carried out using the surface area analyzer (Micromeritics ASAP 2020) and the Field Emission Scanning Electron Microscope (FESEM) to determine which set of parameters produces the largest surface area estimated using the BET theory (SBET) which is directly related to the effectiveness of that particular adsorbent. Based on the characterization results, sample A20 which is of particle size of 0.25mm, activated using H3PO4 at 1:1 impregnation ratio, carbonized at 400°C for 2 hours, is found to have the largest SBET (256.63m2/g). The total pore volume (VT) of sample A20 is 0.01356cm3/g while its average pore diameter (D) is 0.247nm. The produced BP based activated carbon samples are also tested for their adsorption capacity with typical pollutants found in industrial waste water such as heavy metal ions as well as oil and grease (O&G) particles. Three heavy metal ions are studied in this project, which are copper (Cu2+), zinc (Zn2+) and lead (Pb2+). The adsorption capacity of sample A20 is specifically studied while being compared to another sample A32. Sample A20 yields higher percentage removal for all tested waste water pollutants, which are 81.6% for crude oil particles, 59.6% for Cu2+, 44.33% for Zn2+ and 84.46% for Pb2+.