Facile Preparation of Water-processable Biochar Based on Pitch Pine and Its Electrochemical Application for Cadmium Ion Sensing

Abstract

The water-processable biochar (BC) based on pitch pine was prepared by dispersing these grinded micropowders into carboxymethyl cellulose (CMC) mixed aqueous dispersion for electrochemical sensing of cadmium ion (Cd2+) in real samples. Biochars was obtained by pyrolyzing the pitch pine under oxygen-limited conditions at 600 °C. Montmorillonite (MMT) was employed for enhancing surface area, adsorption capacity, ion-exchange ability and dispersive stability. Carboxymethyl cellulose was selected for enhancing water-dispersive ability, film-forming ability, adhesive ability. BC-CMC-MMT composites displayed synergistically enhanced ability like surface area, adsorption capacity and stripping response towards Cd2+, which was employed as cost-effective electrode modified material for voltammetric determination of Cd in linear range of 2.0 × 10-8 – 8 × 10-5 M with limit of detection of 6.7 nM, remarkable selectivity, and good practicability. Satisfactory sensing performance indicated that low-cost water-processable BC has practical values and serves as sensing material for electrochemically determining heavy metal ions in real samples.