Gas Solid Gas Chromatography

IP345/80 describes the use of a 3mx 2.3 mm stainless-steel column containing Porapak R for the separation of nitrogen, oxygen and carbon dioxide and hydrocarbons up to C8 in the gas above crude oil. The method requires programming the column from — 50°C to 240°C, which is unattractive in that it requires a supply of coolant such as liquid nitrogen.

Although the superior separation characteristics of adsorption materials in porous-layer open-tubular (PLOT) columns were recognized, the main problem was that the preparation procedures for PLOT columns are complex and difficult to implement. However, with the introduction of new capillary column coating technology it is now possible to deposit stable layers of adsorbents on the inner wall of fused silica capillaries. These columns give better separations in a shorter time than the older packed columns.

Adsorption materials that are now commercially available in capillary columns are aluminium oxides, molecular sieves, activated carbon such as graph-itized carbon black, porous polymers and silica. Besides fused silica capillary columns, the adsorbents are also deposited in metal columns, expanding the application of adsorbents in the area of process analysers and portable equipment.

Each adsorbent has its own specific application field, as summarized in Table 1. In general the application field of PLOT columns covers the permanent gases and volatile mixtures with boiling points up to c. 225°C.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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