Many times these composites meet as misturashomogneas of different substances, what it makes it difficult the analysis of the necessary sample etorna the use of one technique of separation for the constituent identificaodos gifts in the sample. The chromatography is a method physicist-chemistry deseparao in which the constituent of the sample are partitiond in two phases, stationary and to another one percola an insoluble fluid that through the first one. The used stationary phase can be a solid or a liquid whereas afase mobile can be a liquid fluid, a gas or a supercritical gas (above critical datemperatura and the high pressures) (Ciola, 1998). The great variety of combinations between mobile phases stationary atorna one extremely versatile technique and of great application. Acromatografia can be used for the composite identification through dacomparao with previously existing standards, for the purificao of compostosseparando substances undesirable and for the separation of the umamistura components (Collins et al, 1993).
The chromatography exists has maisde one hundred years and, sensitivity, speed, exactness and simplicity substance paraseparao, identification and determination, had resulted in a grandedesenvolvimento of this method throughout the time. They exist different modalidadesde chromatography and them 70% of Analticarealizada Chemistry are responsible for more than nowadays (Neto and Nunes, 2003). The techniques cromatogrficaspodem to be classified of different used forms that vary fasesmvel in accordance with and stationary in the method. Table 1 presents the possveisclassificaes how much the nature of the phases for the processes chromatographic. It lowers the complete article to continue reading.