Determination of the phosphate adsorption potential of biochar derived from Ananas comosus (pineapple) peels in aqueous solution

CAELAN PHILIP B. DIAZ, NIKO EMMANUEL GOLO, NICOLE M. VILLALUNA, and ATHENES JOY PRESNO – ABAN

Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology, Philippines

Abstract

The increased demand and use for phosphate around the world have caused the global phosphate level to rise. Adsorbents such as biochar are commonly used to remediate heavy metals, but research has also shown its potential to remediate excess nutrients. Pineapple peels were proven to contain magnesium which can aid phosphate adsorption and can be used as a potential biochar feedstock. The study aimed to determine the potential of pineapple peel derived biochar in adsorbing phosphates. Pineapple peel biochar were produced via pyrolysis at 300 °C, 400 °C, and 500 °C, and then characterized using a Fourier Transform Infrared (FTIR) spectrometer. Biochar analysis showed biochar decomposition as pyrolysis temperature was increased. Phosphate analysis showed positive adsorption rates at 25 ppm concentrations but showed negative adsorption rates at lower concentrations. The results showed a general inverse relationship between the biochar adsorption capacity and pyrolysis temperature which directly contradicts previous research.

Keywords: pineapple peels, Ananas comosus, phosphate, adsorption, biochar