ABSTRACT
Objective To prepare 4-sulfonylcalix[6]arene-modified cotton fibers for adsorption and removal of uranium based on the specific complexation of calix[6]arene with uranium (VI). Methods Chemical grafting was used for the modification of cotton, which reacted with α-bromoisobutyryl bromide, glycidyl methacrylate, and 4-sulfonylcalix[6]arene. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FTIR) were used to characterize the structure of 4-sulfonylcalix[6]arene-modified cotton (Cotton S-C[6]a). A Franz diffusion cell was used to simulate uranium-contaminated skin. Laser fluorimetry was used to determine the uranium content. Results SEM, XPS, and FTIR showed that cotton fibers were successfully grafted with 4-sulfonylcalix[6]arene. The optimal conditions of Cotton S-C[6]a for the adsorption of uranium (VI) was pH 4.0, duration of 20 min, and 20 mg of adsorbent. The adsorption process fitted well with pseudo-secondary-order kinetics. The uranium removal efficiency of Cotton S-C[6]a was up to 78.46% in aqueous solution and 81.72% on skin. Conclusion The synthesized Cotton S-C[6]a is highly efficient in the removal of uranium (VI) in solution and on contaminated skin.