Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
169 words
A method of recovering hydrofluoric acid, said method comprising: stripping a mixture containing at least HF, water, and acid soluble oil by contacting the mixture with a vaporous hydrocarbon in a fractionation column; recovering as an overhead product from said column a vaporous mixture of HF and vaporous hydrocarbon; collecting a second mixture of HF, water and acid soluble oil in a lower portion of said column; removing a portion of said second mixture from said column, cooling the thus removed portion of said second mixture to a temperature no higher than approximately 125° F; phase separating the thus cooled portion of said second mixture into a first continuous acid soluble oil phase portion containing acid soluble oil which is substantially free of HF, and a second continuous acid soluble oil phase portion containing a major portion of the HF contained in the second mixture and acid soluble oil; separating said second portion from said first portion; and returning the thus separated second portion containing HF to said column.
Claim 2
Independent Claim
169 words
A method of recovering hydrofluoric acid, said method comprising: stripping a mixture containing at least HF, water, and acid soluble oil by contacting the mixture with a vaporous hydrocarbon in a fractionation column; recovering as an overhead product from said column a vaporous mixture of HF and vaporous hydrocarbon; collecting a second mixture of HF, water and acid soluble oil in a lower portion of said column; removing a portion of said second mixture from said column, cooling the thus removed portion of said second mixture to a temperature no higher than approximately 125° F; phase separating the thus cooled portion of said second mixture into a first continuous acid soluble oil phase portion containing acid soluble oil which is substantially free of HF, and a second continuous acid soluble oil phase portion containing a major portion of the HF contained in the second mixture and acid soluble oil; separating said second portion from said first portion; and returning the thus separated second portion containing HF to said column.
Claim 3
Dependent Claim
58 words
A method as set forth in claim 1 wherein: said portion of said second mixture is cooled by indirect contact with a cooling hydrocarbon; and including introducing at least a first portion of the cooling hydrocarbon into the column after the first portion of cooling hydrocarbon has been used for cooling of said portion of the second mixture.
Claim 4
Dependent Claim
62 words
A method as set forth in claim 2 wherein: a second portion of said cooling hydrocarbon is used as a working fluid to contact and return the recovered second portion of said continuous ASO phase to the column by eduction; and including heating said first portion of said cooling hydrocarbon before introducing said first portion of said cooling hydrocarbon into said column.
Claim 5
Dependent Claim
34 words
A method as set forth in claim 1 wherein: said thus separated second portion contains up to about 90 percent of the acid soluble oil contained in the cooled portion of said second mixture.
Claim 6
Dependent Claim
25 words
A method as set forth in claim 4 including: heating said thus separated second portion before recycling said thus separated second portion to said column.
Claim 7
Independent Claim
247 words
A method of recovering hydrofluoric acid, said method comprising: stripping a mixture containing at least HF, water and acid soluble by contacting the mixture with vaporous hydrocarbon in a fractionation column; recovering as an overhead product from said column a first mixture of HF and vaporous hydrocarbon; collecting a second mixture of HF, water and acid soluble oil in a lower portion of said column; removing a portion of said second mixture from said column and cooling the thus removed portion of said second mixture by indirect contact with a cooling hydrocarbon to a temperature no higher than about 125° F.; phase separating the thus cooled portion of said second mixture into a first continuous acid soluble oil phase portion containing acid soluble oil which is substantially free of HF, and a second continuous acid soluble oil phase portion containing a major portion of the HF contained in the second mixture and acid soluble oil, with said acid soluble oil in the second phase portion being up to about 90 percent of the acid soluble oil contained in the thus cooled portion of said second mixture; separating said first phase portion from said second phase portion; returning the thus separated second phase portion containing HF to said column; and introducing at least a portion of the cooling hydrocarbon into said column as at least a portion of said vaporous hydrocarbon after the portion of cooling hydrocarbon has been used for cooling said portion of said second mixture.
Claim 8
Independent Claim
247 words
A method of recovering hydrofluoric acid, said method comprising: stripping a mixture containing at least HF, water and acid soluble by contacting the mixture with vaporous hydrocarbon in a fractionation column; recovering as an overhead product from said column a first mixture of HF and vaporous hydrocarbon; collecting a second mixture of HF, water and acid soluble oil in a lower portion of said column; removing a portion of said second mixture from said column and cooling the thus removed portion of said second mixture by indirect contact with a cooling hydrocarbon to a temperature no higher than about 125° F.; phase separating the thus cooled portion of said second mixture into a first continuous acid soluble oil phase portion containing acid soluble oil which is substantially free of HF, and a second continuous acid soluble oil phase portion containing a major portion of the HF contained in the second mixture and acid soluble oil, with said acid soluble oil in the second phase portion being up to about 90 percent of the acid soluble oil contained in the thus cooled portion of said second mixture; separating said first phase portion from said second phase portion; returning the thus separated second phase portion containing HF to said column; and introducing at least a portion of the cooling hydrocarbon into said column as at least a portion of said vaporous hydrocarbon after the portion of cooling hydrocarbon has been used for cooling said portion of said second mixture.
Claim 9
Dependent Claim
59 words
A method as set forth in claim 6 wherein: said portion of cooling hydrocarbon introduced into the column is heated before introducing said portion of cooling hydrocarbon into said column; and at least a portion of said cooling hydrocarbon is used as a working fluid to contact and return said separated second phase portion to said column by eduction.