Abstract: The present invention is directed to an electrodepositable coating composition comprising an electrodepositable binder comprising an ionic salt group-containing film-forming polymer comprising active hydrogen functional groups, and a blocked polyisocyanate curing agent; a solubilized bismuth catalyst; and a guanidine; wherein the electrodepositable coating composition has a weight ratio of bismuth metal from the solubilized bismuth catalyst to guanidine of from 1.00:0.071 to 1.0:2.1 and/or a molar ratio of bismuth metal to guanidine of from 1.0:0.25 to 1.0:3.0. Also disclosed are methods of treating electrodepositable coating compositions, methods for making electrodepositable coating compositions, systems for coating a metal substrate, coatings, coated substrates, and methods of coating a substrate.

Abstract: Disclosed is a continuous process for purifying contaminated waste water. First the water passes through an equalization zone including at least two separate compartments, in one of which the pH of the water is adjusted to a range of from about 6.5 to 9.5. The water flows through the separate compartments such that the concentration of contaminants in the water exiting the equalization zone will approach about constant concentration which changes only gradually even though influent contaminant concentration changes rapidly. Water in at least one compartment of the equalization zone is aerated so that the dissolved oxygen in the water is at least three parts of dissolved oxygen per million parts of water. Solids are skimmed from the surface of the water in the zone, and coagulant is added to the effluent water from the equalization zone so that colloidal particles in the water flocculate. The water from this equalization zone is then filtered to remove flocculated particles.