Monday 8 May 2017

Adsorbents/Desiccants for Successful Chromatography Process

Chromatography- An Overview

Chromatography is a separation process mainly used to segregate different components of any given mixture. The various components are separated so that they can be taken for further analysis. This is not possible if they are still part of the mixture, so it can only be done only after separation. This is where the role of chromatography becomes important. Chromatography is much in demand for separating mixtures for two reasons.1) it gives best results in minimum time possible and 2) it is very cost effective as components can be separated with less expenditure.   

Chromatography can be divided into many categories, depending on the components, which need to be separated. These include column chromatography, flash chromatography, thin-layer chromatography, gas and liquid chromatography. All these forms of chromatography use different chromatography adsorbents and chromatography desiccants and have varied purposes.  

How the Chromatography Process Functions

The process of chromatography is very simple and works on the principle of components of any given mixture separating at different levels, based on the relative dissolving capacity of each solute. In chromatography, there are generally two phases.The mobile or liquid phase and the solid or stationary phase. The mobile phase consists of a moving liquid stream while the solid phase is contiguous. While the mobile phase can either be a liquid or a gas, the stationary phase is usually a solid or liquid. The solid phase makes use of chromatography adsorbents like Silica Gel, Activated Alumina to absorb different components of the mixture at different levels.

When the chromatography process begins, then the mixture, which has to be separated is placed on top of the column. Next, the liquid solvent is passed through the column. It moves downwards with the help of gravity or externally applied pressure. As the mixture moves downwards, its various components will be absorbed by the chromatography desiccants and will settle at different levels. When the mixture finally reaches the bottom, that is when the separation is completed. The individual components, also known as elutants, are taken as solvent drips from the column end.

Chromatography Adsorbents/Desiccants

As mentioned earlier, the chromatography process required chromatography adsorbents and desiccants. These chromatography, especially column chromatography adsorbents, are required to absorb the components at different levels. Chromatography desiccants like Silica Gel, Carbon and Activated Alumina have great absorption capacities and therefore are the best choice.

When the components move down in the vertical glass column, where the mixture is being separated, they will be absorbed by the chromatography adsorbents based on their acidity or alkaline nature. It is on the basis of this acidic/alkaline nature of the components that the chromatography desiccants are selected. Only that desiccant is chosen, which will work well with the components so that they are successfully separated. Once they divided, these components will be taken for further analysis.
Supplier of column chromatography materials like Sorbead India always ensure that top-quality chromatography adsorbents like Silica Gel are made available to companies. The company is one of the most well-known adsorbents supplier for column chromatography in the country.