in this work, a new adsorbent was prepared by microencapsulation of sulfoxine into chitosan microspheres by the spray drying technique. the new adsorbent was characterized by raman spectroscopy, scanning electron microscopy and microanalysis of energy dispersive x-rays. the cu(ii) adsorption was studied as a function of ph, time and concentration. the optimum ph was found to be 6.0. the kinetic and equilibrium data showed that the adsorption process followed the pseudo second-order kinetic model and the langmuir isotherm model over the entire concentration range. an increase of 8.0% in the maximum adsorption capacity of the adsorbent (53.8 mg g-1) was observed as compared to chitosan glutaraldehyde cross-linked microspheres.