Methods for recovering organic salts from industrial process streams

A method for recovering an organic salt in a Bayer or Sinter process for the production of alumina, comprising:

• (a) contacting an organic salt liquid phase comprising at least one organic salt with an aqueous process stream of the Bayer or Sinter process for the production of alumina for the removal of at least one impurity from the aqueous process stream and transfer of the at least one impurity to a primarily organic phase comprising the organic salt and the at least one impurity, and producing an impurity laden organic salt stream comprising the primarily organic phase, wherein the at least one impurity comprises oxalate;
• (b) recycling the organic salt, wherein the recycling comprises removing at least a portion of the at least one impurity from the impurity laden organic salt stream, wherein the contacting and/or the recycling generate at least one aqueous exit stream which comprises a portion of the organic salt from the organic salt liquid phase;
• (c) intermixing the at least one aqueous exit stream with an amount of an inorganic salt to form a biphasic mixture and allowing the biphasic mixture to form an organic salt reduced aqueous solution phase and a primarily organic salt phase, wherein the amount of the inorganic salt in the biphasic mixture is effective to form the organic salt reduced aqueous solution phase and a primarily organic salt phase, wherein the primarily organic salt phase comprises the portion of the organic salt;
• and
• (d) recovering the primarily organic salt phase;
• wherein the at least one organic salt comprises:
• a cation selected from the group consisting of phosphonium, ammonium, sulfonium, pyridinium, pyridazinium, pyrimidinium, pyrazinium, pyrazolium, imidazolium, thiazolium, oxazolium, pyrrolidinium, quinolinium, isoquinolinium, guanidinium, piperidinium and methylmorpholinium, and
• an anion selected from the group consisting of fluoride, chloride, bromide, iodide, hydroxyl, alkylsulfate, dialkylphosphate, sulfate, nitrate, phosphate, sulfite, phosphite, nitrite, hypochlorite, chlorite, chlorate, perchlorate, carbonate, bicarbonate, carboxylate, bis(trifluoromethylsulfonyl)imide ([NTF2]−), tetrafluoroborate, and hexafluorophosphate.