Abstract: An immunoglobulin-rich fraction containing IgG, IgA and IgM is prepared in high concentration (200 mg/ml) by contacting diluted serum with CuSO.sub.4, which is a source of strong positive ions, to produce a precipitate rich in immunoglobulins, whereafter the precipitate is washed with an EDTA chelating agent solution and then a solution of L-lysine.HCl and NaHCO.sub.3 is added to form a colloidal solution of the washed immunoglobulin precipitate.

Abstract: A cryogenic air separation system is described in which pressure-swing adsorption driers are used to remove virtually all of the moisture from the feed air prior to the passage of the feed air stream through reversing heat exchangers which remove the carbon dioxide. The reversing heat exchangers are regenerated by at least one outgoing product nitrogen stream, while the adsorption driers are regenerated by all or a portion of a low pressure stream withdrawn from the low pressure column the composition of which may be rich in either nitrogen or oxygen depending upon whether the volume of product nitrogen or oxygen is to be maximized. A portion of this low pressure stream may be recovered as a dry product stream, while an additional stream of high purity product oxygen may also be recovered.