Potential of Several Biomass as Biochar for Heavy Metal Adsorbent

Biochar is a negatively charged recalcitrant carbon that has the potential to adsorb heavy metals. This research aim was to identify the best type of biomass with a simple combustion process (Kiln) in producing carbon, base cations, organic acids, the highest surface area and pores with more porous morphology. The type of biomass used was paddy straw, rice husk, coconut fiber, oil palm empty fruit bunch. Instrument to observe the morphology, carbon content and a number of Biochar bases using Scanning Electron Microscope (SEM-EDAX), to observe the surface and pores (m2 / g) using Brunauer Emmet Teller (BET), and to observe functional groups type using Fourier Transform Infrared Spectroscopy (FTIR). The research results showed that coconut fiber biomass had the highest surface area of 23.9145 m2 / g but rice husk had a larger pore volume and pore size of 0.026962 m3 / g and 63.6994 4V / A respectively. The highest percentage of carbon was found in rice husk biochar by 77.18% with an atomic percentage of 86.43%. The functional group was dominated by Phenolic (OH), Carboxyl, Ether and Esters groups with a frequency of 1050-1300 and the highest frequency was in Rice Husk Biochar. Cation in biochar was dominated by K+ with the highest percentage of rice husk by 2.75%, Na+ was also found in rice husk by 1.07%, while Mg2+ was in Biochar of oil palm bunches by 0.63%. Porous morphology was seen in rice husks with ˃ 1000 magnification, so rice husk biochar has the best potential as heavy metals adsorption.