Chemically Modified Coconut Shell Biochar for Removal of Heavy Metals from Aqueous Solution

Abstract

In this study, coconut shells were converted into biochar via pyrolysis and chemically modified via an acid-base treatment to enrich its adsorption capabilities. Batch experiments were carried out to analyze the adsorption potential of the modified coconut shell (MCSC) or removal of chromium, nickel, and copper from aqueous solution. The chemical modification increased the surface area of MCSC to 185.712 m2/g. Batch adsorption study using MCSC resulted in 99% removal of copper, 95% (nickel), and 39% (chromium). The adsorption of studied metal ions fitted well with Langmuir isotherm, showing a monolayer adsorption process. A kinetic analysis showed that all the samples match a strong correlation coefficient in pseudo-second-order (R2>0.95), indicating the occurrence of a chemical adsorption process.

Mechanism of Oxytetracycline Removal by Coconut Shell Biochar Loaded with Nano-Zero-Valent Iron

“…Compared with other biochar raw materials, coconut shell has the largest surface area and porosity. Meanwhile, the coconut shell has the advantages of low ash content, high density, and high mechanical strength, making it suitable as a raw material for the adsorption of pollutants [ 21 , 22 ]. Shen et al reported that coconut shell biochar has a good removal effect on Cr (VI) due to its rich functional groups [ 23 ].…”