Sealed vials containing improved Karl Fischer solutions, and process for water determination using these vials

A process for the colorimetric determination of the water content of a sample, comprising the steps of:

• providing a sealed vial having a first section of approximately constant diameter including a scoremark and an elastic enclosure means surrounding said first section in the vicinity of said scoremark, said vial being sealed and containing a Karl Fischer solution therein of volume V.sub.0, said solution including a reducing ion, alcohol, imidazole or its derivatives, iodine in an amount less than about 0.02 moles per liter, and iodide,
• measuring a first optical absorbance A1 of said Karl Fischer solution,
• breaking said vial along said scoremark to produce discrete pieces,
• injecting a sample volume V.sub.S of unknown water content into said vial by a syringe whose needle penetrates said elastic means and passes through a separation between said discrete broken pieces of said vial,
• mixing said sample and said Karl Fischer solution in said vial, said elastic enclosure means substantially preventing the contents of said vial from being exposed to the atmosphere,
• measuring a second optical absorbance A2 of the sample-Karl Fischer mixture,
• computing from the difference of said first and second optical absorbances the water content of said sample.

A process for the colorimetric determination of the water content of a sample using a Karl Fischer reaction, comprising the steps of:

• providing a sealed vial containing therein a volume V.sub.0 of Karl Fischer solution including SO.sub.2, a buffer, iodine in an amount less than 0.005 moles per liter, iodide and a solvent,
• measuring a first optical absorbance A1 of said Karl Fischer solution in said sealed vial,
• puncturing the seal of said vial by injecting therethrough a sample volume V.sub.S of unknown water content into said sealed vial, to produce a mixture of said sample and said Karl Fischer solution,
• measuring a second optical absorbance A2 of said mixture including said sample and said Karl Fischer solution, and
• computing the amount of water in said sample from the difference of said first and second optical absorbances.

A process for the colorimetric determination of the water content of a sample using a Karl Fischer reaction, comprising the steps of:

• providing a sealed vial containing therein a volume of Karl Fischer solution including SO.sub.2, a buffer, iodine, iodide, and a solvent,
• measuring a first optical absorbance of said Karl Fischer solution in said sealed vial,
• adding a sample volume of unknown water content to said sealed vial,
• measuring a second optical absorbance of a mixture including said sample and said Karl Fischer solution, and
• computing the amount of water in said sample from the difference of said first and second optical absorbances,
• where said sealed vial has a portion thereof enclosed in an elastic enclosing means wherein said sample is introduced into said vial by breaking said vial into discrete parts held together by said elastic enclosing means and piercing the elastic enclosing means with a syringe needle, said sample being introduced into said vial in a fixed amount from said syringe.

A process for the colorimetric determination of the water content of a sample using a Karl Fischer reaction, comprising the steps of:

• providing a sealed vial containing a Karl Fischer solution including SO.sub.2, a buffer including imidazole or its derivatives, iodine in an amount less than about 0.005 moles per liter, iodide, and a solvent including a halogenated hydrocarbon in an amount at least about 20% by volume,
• measuring a first optical absorbance of said Karl Fischer solution in said sealed vial,
• breaking the seal of said vial by injecting therethrough a sample of unknown water content to produce a mixture including said Karl Fischer solution and said sample,
• measuring a second optical absorbance of said mixture including said sample and said Karl Fischer solution, and
• computing the amount of water in said sample from the difference of said first and second optical absorbances.

A process for the colorimetric determination of water content of a sample, comprising the steps of:

• providing a sealed vial having a section of approximately constant diameter including a scoremark and an elastic enclosure means surrounding said section in the vicinity of said scoremark, said vial being sealed and containing a Karl Fischer solution therein of known volume V.sub.0, said solution including a reducing ion, alcohol, a buffer, iodine in an amount less than about 0.005 moles per liter and iodide,
• breaking said vial along said scoremark to produce discrete pieces, said vial being substantially sealed from the atmosphere by said elastic enclosure means,
• adding a sample of known volume V.sub.S of unknown water content into said vial, said sample being injected into said vial through the seal of said elastic enclosure means,
• mixing said sample and said Karl Fischer solution in said vial, said elastic enclosure means substantially preventing the contents of said vial from being exposed to the atmosphere, and
• observing any change in color that occurs when said sample is added as an indication of the water content of said sample.