Direct removal of trace ionic iodide from acetic acid via porous carbon spheres.

The main purpose of this paper is to report the direct removal of trace ionic iodide (I(-)) from acetic acid through porous carbon spheres (PCS) derived from the carbonization of poly(vinylidene chloride). The surface morphology and pore size distribution of the PCS are distinct from activated carbon (AC); thus they possess the peculiar performance of removing ionic iodide from acetic acid. The easy reach of micropores in the PCS was different from that of AC, but similar to that of activated carbon fiber (ACF). The iodide removal process has a strong relation with temperature, which is a typical feature of physical adsorption. The ionic iodide content in acetic acid used in the adsorption experiment was at the parts per billion level, and the factors influencing the adsorption are discussed in detail.