Perchlorate: regulatory and patent follow-up

The EPA fact sheet on perchlorate it is a good source of information on the origins of the chemical and why the EPA has decided to regulate it.  The fact sheet describes how perchlorate comes from “rocket fuel, fireworks, flares and explosives.”  It goes on to describe how perchlorate is known to have adverse health effects, is repeatedly found in unhealthy quantities in public water systems, and that there is a meaningful opportunity to improve health by decreasing exposures.  It should be understood that the EPA is not beginning to regulate perchlorate, it is merely starting the process of deciding if and how to regulate perchlorate.

Patent technology notes:

  1. United States Patent 7,850,854 to Gurol, et al. teaches removal of perchlorate from liquids through the use of activated carbon. The activated carbon adsorbs the perchlorate from the liquid followed by the regeneration of the activated carbon with sodium borohydride.
  2. United States Patent 7,635,236 to Zhao et al. teaches that zero valent iron can be used to destroy perchlorate. The invention utilizes either starch or cellulose to create a suspension containing the zero valent iron. The disclosure tends to indicate that compounds such as carboxymethyl cellulose aid in the dispersion and stability of the zero valent iron.  As a side note, Zhao also teaches that the inventive compositions are useful for the reduction of nitrates.