An important and central aspect of the present invention is the use of expanded amorphous aluminum silicate (EAAS) as a vehicle for a chlorite salt. This vehicle, when exposed to moisture, will release chlorine dioxide (ClO2) for purposes of deodorization or microbial suppression. Thus, where a particular area or volume is to be deodorized or made less microbally contaminated, the EAAS-chlorite salt (most preferably sodium chlorite) is placed in the area or volume to be treated and moisture is permitted to interact with the material. The result of the moisture is to permit the chemical reaction (presumably acidification) of the chlorite salt to yield chlorine dioxide gas. While normal EAAS has some inherent acidity, the inherent acidity is low enough so that, even when a chloride salt is encapsulated in the EAAS and the resultant mixture exposed to moisture, ClO2 release is very slow and over an extended period. Under most conditions, a more rapid release of ClO2 is desired for deodorization and/or sterilization. A more rapid release of chlorine dioxide may be accomplished by first treating the native EAAS with an acid, preferably a protic acid, to acidify chemical groups of the EAAS. After native EAAS is acidified and dried, if necessary, a chlorite salt such as sodium chlorite is incorporated therein.