What are the Various Types of Ion Exchange Materials?
Ion exchange materials are basically of two types: cation and anion exchangers. Cation exchange materials react only with positively charged ions such as Ca++ and Mh++. Anion exchanger materials react only with the negatively charged ions such as carbonate (CO3-) and sulphate (SO4-). Zeolite materials are cation exchangers composed chiefly of sodium, alumunium and silica. There are several other types of cation exchange materials of an organic or resinous nature. The anion materials are usually organic in nature and are of two basic types: weak base and strong base types. Weak base exchagers don稚 take out carbon dioxide or silica (actually carbonic acid and silica acid) but remove strong acid anions by a process that is more like adsorption than ion exchange. Strong base anion exchangers on the other hand can redce silica and carbon dioxide to very low values. Cation exchangers usually opcles which settle out readily. In these cases clarifi-cation equipment merely involves the use of s
