Boron adsorption by clinoptilolite using factorial design

In this article, boron removal from aqueous solutions by batch adsorption was investigated and 23 full factorial design was applied. Three parameters affected the performance and two levels of these parameters were investigated. The chosen parameters were temperature (25 degrees C and 45 degrees C), pH (3 and 7), and mass of adsorbent (0.1 g and 1 g). The significance of the effects was checked by analysis of variance (MINITAB-Version 15). The model-function equation for boron adsorption on clinoptilolite was obtained. The results showed that temperature, pH, and mass of adsorbent affected boron removal by adsorption. Boron removal increased with increasing pH and adsorbent dosage, but decreased with increasing temperature. The optimum conditions were found as pH = 7, adsorbent dosage = 1 g/25 mL solution, and temperature = 25 degrees C by using factorial design. In addition, the effects of pH, temperature, adsorbent dosage, and initial boron concentration on boron removal were investigated. The adsorption isotherm studies were also performed. Maximum adsorbent capacity (qo) was calculated as 3.64 mg/g. (C) 2010 American Institute of Chemical Engineers Environ Prog, 2010