GEL-ENCAPSULATED NANOPARTICLES AND THEIR ARSENIC-REMOVAL PROPERTIES
David Ramirez, Juan Noveron.
The University of Texas at El Paso, El Paso, TX.
Arsenic (As) is an element that occurs in 200 different natural mineral forms such as arsenates, sulphides, sulfosalts, arsenides, and arsenites, but most concerning are the 2 forms that are found in significant quantities in natural waters: arsenite (AsO33-) and arsenate (AsO43-). They are toxic to both plants and animals due to their similarity to the analogous phosphite and phosphate, respectively. Current methods for arsenic removal from water rely on iron hydroxide dust that adsorbs the oxo ions, but this process is inefficient and requires large quantities of iron and can only be done in large-scale facilities. New materials that remove arsenate from water and can pave the way to decentralized water treatment technologies are warranted. Our research focuses on developing nanoparticles trapped within hydrogels that uptake arsenate on their high surface area. We have synthesized a copolymer gel that tightly binds transition metal ions and on redox reactions forms nanoparticles with a wide variety of chemical compositions. We will present the synthesis and characterization of gel-encapsulated nanoparticles with [M(II)(O)x(OH)y]n composition, in which M (first-row transition metal), x, y, and n are systematically varied. Their arsenate-removal properties, measured with ICP, will be presented.