Adsorption of Carbadox onto Rice Husk Biochar in Aqueous Solution Influence of Humic Acid and pH Effect

Abstract

The potential release of carbadox (CBX) a commonly used antibacterial agent in swine husbandry into water systems is of a concern due to its carcinogenic and genotoxic effects To the best of our knowledge until this study the adsorption of carbadox onto biochar in aqueous solution has yet to be investigated In this work rice husk biochar a mass productive by-product of biomass slow pyrolysis was adopted as an adsorbent to remove carbadox from aqueous solution The experimental isotherm was analyzed by applying the Langmuir (L) –Freundlich (F) models Very good agreement was observed between the experimental points and fitted lines for all studied adsorption systems; the values of correlation coefficients R2 given figure are close to unity It means that LF models describe well the analyzed experimental data To further explore the role of humic acid (HA) in carbadox sorption on rice husk biochar various concentrations (2~10 ppm) of HA were co-introduced to biochar with carbadox in the sorption systems In general carbadox sorption on biochar increased with increasing HA concentration from 2 to 10 ppm Moreover the maximum adsorption capacities were calculated as 31 35 31 55 and 33 μmol/g for 2 5 and 10ppm humic acid concentration respectively And results revealed that the influence of HA on carbadox sorption was dependent on HA concentration whereas the initial pH of solution has small effects on carbadox adsorption under the experimental conditions

Date of Award	2016 Jun 29
Original language	English
Supervisor	Wan-Ru Chen (Supervisor)