The adsorption of Cr(VI) and organic matter by new generation pyrolysis char

Abstract

Waste vehicle tires (WT) and high density polyetylene (HDPE) were pyrolyzed at 300, 500 and 700°C by slow pyrolysis. Solid product (pyrolysis char) were collected and pyrolysis char was used as adsorbent for COD and Cr(VI) removal. The char samples were characterized by BET, EDS, SEM and XRD analysis. Based on the BET, SEM and XRD results of the char samples, WT 700 can be used as adsorbents for Cr (VI) and organic material adsorptions. Cr(VI) and COD removal efficiency of char adsorbent were investigated. In the adsorption experiments, char was used as 0.1-0.5 g/100 mL doses and at 50°C and 80°C adsorption temperatures. The effects of adsorption temperature and char dosage on the adsorption efficiency were invesitigated. The maximum Cr(VI) adsorption capacity of this new generation char was found to be 14.09 mg/g for 80°C adsorption temperatures. 0.5 g/100 mL adsorbent dose was bettter in COD and Cr (VI) removals. The correlation of PSD1 (pseudo first order kinetic model) was better than PSD2 (pseudo second order kinetic model) for all doses. The Temkin and Langmuir isotherms were better isotherm for COD and Cr(VI) removals, respectively. A new approach were present to evaluation of waste HDPE and waste tires with this study.