A process for recovering nitric acid or salts thereof, comprising: contacting, in the presence of water, an water-immiscible ionic liquid of the formula [A.sup.+][X.sup.−], wherein [A.sup.+] represents a phosphonium or ammonium cation and [X.sup.−] represents a counter anion which is NO.sub.3.sup.−, an halide anion displaceable by NO.sub.3.sup.−, or both, with a fluid which contains HNO.sub.3 and at least one more mineral acid, or precursors of said acids, and partition, under mixing, said acids between aqueous and organic phases and form nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 where Z indicates a molar amount of nitrate held in the ionic liquid beyond the positions occupied by the nitrate counter ions; separating the so-formed mixture into an organic phase comprising a nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 and an aqueous phase consisting of a nitrate-depleted aqueous solution that contains the other mineral acid(s); stripping the nitric acid from said nitrate-loaded ionic liquid to create an aqueous nitrate solution and regenerate ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z≥0 with reduced nitrate loading, or unloaded [A.sup.+][NO.sub.3.sup.−].sub.z=0 ionic liquid.

A process for recovering nitric acid or salts thereof, comprising: contacting, in the presence of water, an water-immiscible ionic liquid of the formula [A.sup.+][X.sup.−], wherein [A.sup.+] represents a phosphonium or ammonium cation and [X.sup.−] represents a counter anion which is NO.sub.3.sup.−, an halide anion displaceable by NO.sub.3.sup.−, or both, with a fluid which contains HNO.sub.3 and at least one more mineral acid, or precursors of said acids, and partition, under mixing, said acids between aqueous and organic phases and form nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 where Z indicates a molar amount of nitrate held in the ionic liquid beyond the positions occupied by the nitrate counter ions; separating the so-formed mixture into an organic phase comprising a nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 and an aqueous phase consisting of a nitrate-depleted aqueous solution that contains the other mineral acid(s); stripping the nitric acid from said nitrate-loaded ionic liquid to create an aqueous nitrate solution and regenerate ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z≥0 with reduced nitrate loading, or unloaded [A.sup.+][NO.sub.3.sup.−].sub.z=0 ionic liquid.

A process for recovering nitric acid or salts thereof, comprising: contacting, in the presence of water, an water-immiscible ionic liquid of the formula [A.sup.+][X.sup.−], wherein [A.sup.+] represents a phosphonium or ammonium cation and [X.sup.−] represents a counter anion which is NO.sub.3.sup.−, an halide anion displaceable by NO.sub.3.sup.−, or both, with a fluid which contains HNO.sub.3 and at least one more mineral acid, or precursors of said acids, and partition, under mixing, said acids between aqueous and organic phases and form nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 where Z indicates a molar amount of nitrate held in the ionic liquid beyond the positions occupied by the nitrate counter ions; separating the so-formed mixture into an organic phase comprising a nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 and an aqueous phase consisting of a nitrate-depleted aqueous solution that contains the other mineral acid(s); stripping the nitric acid from said nitrate-loaded ionic liquid to create an aqueous nitrate solution and regenerate ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z≥0 with reduced nitrate loading, or unloaded [A.sup.+][NO.sub.3.sup.−].sub.z=0 ionic liquid.

A process for recovering nitric acid or salts thereof, comprising: contacting, in the presence of water, an water-immiscible ionic liquid of the formula [A.sup.+][X.sup.−], wherein [A.sup.+] represents a phosphonium or ammonium cation and [X.sup.−] represents a counter anion which is NO.sub.3.sup.−, an halide anion displaceable by NO.sub.3.sup.−, or both, with a fluid which contains HNO.sub.3 and at least one more mineral acid, or precursors of said acids, and partition, under mixing, said acids between aqueous and organic phases and form nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 where Z indicates a molar amount of nitrate held in the ionic liquid beyond the positions occupied by the nitrate counter ions; separating the so-formed mixture into an organic phase comprising a nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 and an aqueous phase consisting of a nitrate-depleted aqueous solution that contains the other mineral acid(s); stripping the nitric acid from said nitrate-loaded ionic liquid to create an aqueous nitrate solution and regenerate ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z≥0 with reduced nitrate loading, or unloaded [A.sup.+][NO.sub.3.sup.−].sub.z=0 ionic liquid.

The present invention relates to a process for the separation of strong acid from its salts. In said process, a strong acid salt is reacted with organic weak base (OWB) in the presence of a hydrophilic solvent and CO.sub.2. The cation of the strong acid salt is precipitated to produce a carbonate/bicarbonate salt and the strong acid form a liquid salt with the OWB. The above process is performed in a solution comprising both the strong acid salt and the WBO. In the next step, the strong acid is released from its OWB liquid salt and the OWB is returned to a previous step.

The present disclosure concerns processes for removal of nitrate from nitrate-rich brines, typically selective removal that permits reclaiming the nitrate after such removal.

The present disclosure concerns processes for removal of nitrate from nitrate-rich brines, typically selective removal that permits reclaiming the nitrate after such removal.