Past and Present Research Systems of Green Chemistry

Biography

Biography: Birgül Benli

Abstract

Arsenic level in natural water sources and rarely drinking water is a serious problem in the west regions of Turkey. Since natural mineralization causes arsenic contaminations, millions of people in more than 70 countries are also probably under the same risk of arsenic poisoning from drinking water. The maximum contaminant level (MCL) for arsenic was revised as 0.010mg/L (10 µg/L) by the United States Environmental Protection Agency (EPA). In the case of Emet and Hisarcik (in Kütahya, Turkey), the arsenic content of primary drinking waters and groundwater’s are determined as generally higher than MCL. High level of arsenic in natural waters was considered to be related with the formation of boron minerals in these regions where the world’s largest borate deposits ever discovered. Besides, an efficient and economic approach for water purification can be adsorption processes. The use of low cost adsorbents provides promising future research on novel porous materials such as synthetic calcium silicates. In this study, rice hull from a rice plant were used for the production of synthetic calcium silicates. Enhanced arsenic removal provided by iron modification of Ca-silicates was also investigated. Produced silicates were characterized by FTIR, X-ray, TGA, particle size and BET surface area analysis. Iron modified adsorbents were found to be completely amorphous materials. Produced adsorbent shows excellent removal efficiency above 99.8%, while pure Ca-silicate from rush hull removed 88%. In other words, iron modified Ca-silicates effort on the 10ppm for initial concentration of arsenic, obtain drinking water with 0.01187ppm arsenic levels below MCL.