Drying techniques organic method

Charles and Simmons [18] have reviewed methods for determining total, inorganic and organic carbon in soils and sediments, particularly limitations and sources of error associated with dry combustion and wet oxidation techniques. Preferred methods, for greater quantitative... 

The indirect method is based on oxidation of the organic substances present by a wet or dry technique and subsequent determination of CO2. 

In the standard method, the metal enclosure (called the air chamber) used to hold the hydrocarbon vapors is immersed in water before the test, then drained but not dried. This mode of operation, often designated as the wet bomb" is stipulated for all materials that are exclusively petroleum. But if the fuels contain alcohols or other organic products soluble in water, the apparatus must be dried in order that the vapors are not absorbed by the water on the walls. This technique is called the dry bomb" it results in RVP values higher by about 100 mbar for some oxygenated motor fuels. When examining the numerical results, it is thus important to know the technique employed. In any case, the dry bomb method is preferred. 

Various techniques have been used for the determination of organic (and total) carbon in sediments. These include both wet and dry combustion methods which depend on the quantitative conversion of the organic (or total) carbon to carbon dioxide [30-32], In addition, an approximate assay technique reported by Bremner and Jenkinson has been used [36]. 

With the exception of instrumental dry combustion methods [32], the techniques referred to above for the analysis of organic (and total) carbon in sediments are time consuming (e.g. 2-3h). An instrumental technique described by Van Hall and Stenger [33] makes use of a non-dispersive infrared detector and measures the carbon dioxide resulting from the combustion of the carbonaceous compounds. Total and inorganic carbon can be differentiated by the use of different combustion columns and temperatures. 

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