Effective and selective removal of cationic dye from aqueous solution using rosin derivative modified wheat straw

ABSTRACT This study developed an effective, low-cost and renewable bioadsorbent to remove dyes from wastewater. Wheat straw, an agricultural by-product with abundant resource, was modified with rosin derivative (maleated rosin) and applied as a biosorbent to improve adsorption capacity and selectivity for cationic dyes [(e.g., methylene blue (MB)]. The effects of pH, contact time, temperature and regeneration on adsorption were investigated and discussed. The MB adsorption capacity of the rosin derivative modified wheat straw was 113.34 mg/g, and low temperature and alkaline environment was in favor of the MB adsorption onto the bioadsorbent. The kinetic data was fitted well by pseudo-second-order kinetic model, and equilibrium adsorption isotherm data was fitted well by Freundlich and Temkin isotherm models. In addition, the bioadsorbent could be regenerated in acid condition and reused for several cycles. All the results indicate that the rosin derivative modified wheat straw is a promising bioadsorbent for wastewater treatment.