Partial freezing purification process

Claim 1

PROCESS FOR PROCURING A PURIFIED SOLVENT FROM AN IMPURE FEED SOLUTION IN A CYCLIC BATCH PROCESS OPERATING SUBSTANTIALLY BATCHWISE ON A CONTINUOUS SUCCESSION OF DISCRETE BATCHES OF MATERIAL IN UNFILLED UNPACKED TANKS OR CONTAINERS OF MINIMUM INTERNAL SURFACE AREA AND MAXIMUM INTERNAL VOLUME THAT PERMIT IGITATION OF ANY BATCH TO ASSURE THAT IT IS A SUBSTANTIALLY HOMOGENEOUS MIXTURE AT ANY DESIRED TIME, SAID PROCESS COMPRISING, SEQUENTIALLY PARTIALLY FREEZING, DRAINING, WASHING AND MELTING A PLURALITY OF DISCRETE BATCHES OF MATERIAL DERIVED FROM THE IMPURE FEED SOLUTION; THE PARTIAL FREEZING OF A BATCH OF SOLUTION WITH HIGHEST SOLUTE CONCENTRATION BEING EFFECTED SUBSTANTIALLY SIMULTANEOUSLY WITH MELTING OF THE BATCH CONTAINING FROZEN SOLVENT AND SOLUTION OF LOWEST SOLUTE CONCENTRATION; WITHDRAWING PART OF THE MOTHER LIQUOR RESULTING FROM THE PARTIAL FREEZING AS CONCENTRATED SOLUTION PRODUCT; WITHDRAWING PART OF THE SOLUTION FROM THE BATCH SUBJECTED TO MELTED AS THE PURIFIED SOLVENT PRODUCT, THE REMAINDER OF THE MELT BEING USED TO WASH THE BATCH WHOSE LIQUID PORTION IS OF NEXT HIGHER SOLUTION CONCENTRATION COMPARED WITH THE MELT;