Preparation and the Release Rate Studies of a New Gel Type Slow-Release Solid Chlorine Dioxide

Abstract

A new gel type slow-release solid chlorine dioxide was prepared by mixing two gels together, which were Super Absorbent Polymer (SAP) absorbing sodium chlorite solution and solid acid solution, respectively. The optimal formula was determined by single factor experiment, and the effect of the temperature on chlorine dioxide release rate was investigated. Using tartaric acid as the solid acid, the release rate peak value of chlorine dioxide is 1.61 mg/h, and the release rate become slower of 1.09 mg/h at 72 h and 0.6 mg/h at 144 h, which shows a smooth and sustaining release process. When the volume of water is 25 mL, the optimal formula is SAP:3.5g, sodium chlorine:1.5g, anhydrous sodium sulfate:1.5g, tartaric acid:2g. The release process became more intense when the temperature became higher. The results indicated that this gel type slow-release solid chlorine dioxide should be suitable for eliminating formaldehyde and stink in the environment.