Abstract: A solar distillation apparatus is provided which employs at least one pan which is adapted to contain a distilland therein and which has its upper portion heated directly by solar radiant energy passing through a transparent cover disposed above the pan and has its lower portion at least partially heated by radiant energy reflected from a reflective inside surface comprising a bottom wall of the apparatus such that simultaneous heating of both the upper and lower portions of the distilland is achieved and results in a more efficient heating and the provision of vapors from such distilland which engage the bottom surface of the cover and condense thereon to define a distillant which because the apparatus and cover are disposed at an angle to a horizontal plane move under the influence of gravity along such bottom surface into a reservoir therefor.

Abstract: There is described a method for the decomposition of aluminum nitrate crystals to alumina comprising the steps of:(a) melting the aluminum nitrate crystals;(b) evaporating from the melted crystals in a once through evaporator at the boiling temperature of the mixture and for a time sufficient to remove water and associated nitric acid and to provide a fluid having an alumina concentration of at least about 18% by weight;(c) decomposing the product of step (b) at a temperature of between about 150.degree. and about 200.degree. C. and recovering the heat of condensation of the resultant vapors;(d) further decomposing the product of step (c) in a fluidized bed decomposer at a temperature of between about 300.degree. and about 400.degree. C. to reduce the residual nitrate concentration in the product to between about 5 and about 10 weight percent;(e) decomposing the product of step (d) in a fluidized bed decomposer at a temperature of between about 500.degree. and about 800.degree. C.