Abstract: Corrosion inhibiting pigments are obtained by partial reduction of a hexavalent chromium compound in aqueous solution obtaining a reaction product containing 5 to 95% of the chromium in lower valent state. In the aqueous reaction mixture there is incorporated a water-soluble or water-dispersible polymeric material capable of reacting with chromate to form an insoluble product therewith and the obtained mixture evaporated to dryness under controlled conditions, followed by subdividing the obtained dry mass to suitable size.

Abstract: This invention provides for an improvement in slurry transport systems, especially coal slurry lines. Instead of the usual use of fresh water resources which, in some geographic areas, are scarce for slurry transport, concentrated brine is used which is prepared from abundant salt water resources. Because of the higher density of this concentrated brine, it is a superior carrier of pulverized material. It dimishes the separation and settling tendency of slurry components during transport and particularly during shutdown. Other advantages in the use of concentrated brine include: freezing point depression which permits ease of transport during winter and at lower temperatures; dust suppression of stored coal; avoidance of spontaneous combustion of stored coal; inhibit freeze packing of dewatered pipeline coal; and diminished extent of corrosion in ferrous metal pipelines as compared to that which might occur with lower concentration brines.

Abstract: Zinc oxide is interacted with an aqueous solution containing a chromium chromate complex obtained through partial reduction of an aqueous solution of chromic acid with an organic reducing agent. The resulting product is dried and the residual solid ground to suitable size for use as a pigment.

Abstract: A chromium chromate complex, obtained by partial reduction of chromic acid in aqueous media with an organic reducing agent, is converted to pigment form by evaporating the resulting aqueous composition to dryness and sub-dividing the obtained solid mass to suitable size. The obtained pigment, with or without intimately associated extenders, incorporated in a conventional vehicle, serves as a corrosion inhibitor in metal coating compositions.