Dry basis is an expression of the calculation in
chemistry,
chemical engineering
Chemical engineering is an engineering field which deals with the study of operation and design of chemical plants as well as methods of improving production. Chemical engineers develop economical commercial processes to convert raw materials int ...
and related subjects, in which the presence of water (and/or other solvents) is neglected for the purposes of the calculation. Water (and/or other solvents) is neglected because addition and removal of water (and/or other solvents) are common processing steps, and also happen naturally through
evaporation and
condensation; it is frequently useful to express compositions on a dry basis to remove these effects.
Example
An
aqueous solution containing 2 g of
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...
and 2 g of
fructose per 100 g of solution contains 2/100=2% glucose on a
wet basis, but 2/4=50% glucose on a dry basis. If the solution had contained 2 g of glucose and 3 g of fructose, it would still have contained 2% glucose on a wet basis, but only 2/5=40% glucose on a dry basis.
Frequently concentrations are calculated to a dry basis using the moisture (water) content :
:
In the example above the glucose concentration is 2% as is and the moisture content is 96%.
:
References
Analytical chemistry
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