Inclusion phenomena of phosphate and ammonium ions in spherically shaped ice

yInclusion phenomena of phosphate and ammonium ions in ice crystals and the behaviour of both ions during melting of the ice crystals were experimenta lly investigated. The experiments were performed by forming spherically sha ped ice from a solution containing phosphate and ammonium ions. Then, the i ce was melted to determine the concentrations of phosphate and ammonium ion s. The maximum concentration of phosphate and ammonium was observed around the center of the ice spheres. During, melting, the concentrations of both ions in the initially effluent solution were higher than those in the later -effusing solution. When the ice spheres were introduced into a solution co ntaining both ions, there appeared a change in the maximum adsorption amoun t, which was followed by a rapid decrease approaching an equilibrium value. (C) 2001 Elsevier Science B.V. All rights reserved.