Ionic pre-concentration XRF identification and analysis device, system and method

A method for identifying and measuring concentrations of elements in fluids, comprising the steps of:

• flowing a fluid through a central flow interelectrode gap of an ionic preconcentration cell separating an upper high specific surface area electrode from a lower high specific surface area electrode of said ionic preconcentration cell by a predetermined interelectrode gap width;
• applying a known voltage differential between said upper high surface area electrode and said lower high surface area electrode while said fluid is flowing through said central flow interelectrode gap;
• exposing said cell to x-rays;
• and
• deducing an identity, or measurement of concentration, of an unknown concentration of at least one element of interest in said a fluid of interest, based on comparing calibration data with test data related to a rate at which photons emitted from said preconcentration cell are detected based on said fluid of interest with said unknown concentration flowing through said central flow interelectrode gap at a known flow rate for a known period of time together with said applying said known voltage differential and said exposing said cell to x-rays, wherein said calibration data is obtained by:
• flowing a fluid of interest containing a known concentration of at least one element of interest through said central flow interelectrode gap at a known rate for a known period of time;
• applying a known voltage differential across said electrodes;
• exposing the preconcentration cell to x-rays;
• and
• acquiring data related to a rate at which photons emitted from said preconcentration cell are detected.

An ionic preconcentration cell apparatus for identifying and measuring concentrations of elements in fluids, comprising:

• an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof, substantially parallel to said upper high surface area electrode;
• a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• fluid flow means for flowing a fluid through said central flow interelectrode gap;
• and
• an upper x-ray transmission window in intimate contact with an upper surface of said upper high surface area electrode;
• said upper x-ray transmission window having:
• an atomic number below 10;
• structural rigidity to support up to 1/10 atm. of pressure without bowing more than approximately 100 microns;
• substantial impermeability relative to said fluid;
• x-ray transparency greater than 90% for characteristic photon energies from an element of interest for which a fluidic concentration is to be measured;
• x-ray scattering therefrom minimized to less than approximately 10% of radiation scattered from a column of said fluid equal to one optical depth in said fluid of a characteristic photonic energy from an element of interest for which a fluidic concentration is to be measured;
• and
• freedom from any single contaminant in excess of 1 part per million, when measured by x-ray fluorescence.

An ionic preconcentration cell apparatus for identifying and measuring concentrations of elements in fluids, comprising:

• an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof, substantially parallel to said upper high surface area electrode;
• a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• fluid flow means for flowing a fluid through said central flow interelectrode gap;
• an upper x-ray transmission window in intimate contact with an upper surface of said upper high surface area electrode;
• and
• a lower x-ray transmission window in intimate contact with a lower surface of said lower high surface area electrode;
• said lower x-ray transmission window having:
• an atomic number below 10;
• structural rigidity to support up to 1/10 atm. of pressure without bowing more than approximately 100 microns;
• substantial impermeability relative to said fluid;
• x-ray transparency greater than 90% for characteristic photon energies from an element of interest for which a fluidic concentration is to be measured;
• x-ray scattering therefrom minimized to less than approximately 10% of radiation scattered from a column of said fluid equal to one optical depth in said fluid of a characteristic photonic energy from an element of interest for which a fluidic concentration is to be measured;
• and
• freedom from any single contaminant in excess of 1 part per million, when measured by x-ray fluorescence.

A method for identifying and measuring concentrations of elements in fluids, comprising the steps of:

• flowing a fluid through a central flow interelectrode gap of an ionic preconcentration cell separating an upper high specific surface area electrode from a lower high specific surface area electrode of said ionic preconcentration cell by a predetermined interelectrode gap width;
• applying a voltage differential between said upper high surface area electrode and said lower high surface area electrode while said fluid is flowing through said central flow interelectrode gap;
• passing x-rays through an upper x-ray transmission window intimately contacting an upper surface of said upper high surface area electrode;
• deducing an identity, or measurement of concentration, of at least one element in said fluid based on a response of said preconcentration cell to said x-rays;
• and
• providing said upper x-ray transmission window having:
• an atomic number below 10;
• structural rigidity to support up to 1/10 atm. of pressure without bowing more than approximately 100 microns;
• substantial impermeability relative to said fluid;
• x-ray transparency greater than 90% for characteristic photon energies from an element of interest for which a fluidic concentration is to be measured by said method;
• x-ray scattering therefrom minimized to less than approximately 10% of radiation scattered from a column of said fluid equal to one optical depth in said fluid of a characteristic photonic energy from an element of interest for which a fluidic concentration is to be measured by said method;
• and
• freedom from any single contaminant in excess of 1 part per million, when measured by x-ray fluorescence.

A method for identifying and measuring concentrations of elements in fluids, comprising the steps of:

• flowing a fluid through a central flow interelectrode gap of an ionic preconcentration cell separating an upper high specific surface area electrode from a lower high specific surface area electrode of said ionic preconcentration cell by a predetermined interelectrode gap width;
• applying a voltage differential between said upper high surface area electrode and said lower high surface area electrode while said fluid is flowing through said central flow interelectrode gap;
• passing x-rays through an upper x-ray transmission window intimately contacting an upper surface of said upper high surface area electrode;
• deducing an identity, or measurement of concentration, of at least one element in said fluid based on a response of said preconcentration cell to said x-rays;
• passing said x-rays through a lower x-ray transmission window intimately contacting a lower surface of said lower high surface area electrode;
• and
• providing said lower x-ray transmission window having:
• an atomic number below 10;
• structural rigidity to support up to 1/10 atm. of pressure without bowing more than approximately 100 microns;
• substantial impermeability relative to said fluid;
• x-ray transparency greater than 90% for characteristic photon energies from an element of interest for which a fluidic concentration is to be measured by said method;
• x-ray scattering therefrom minimized to less than approximately 10% of radiation scattered from a column of said fluid equal to one optical depth in said fluid of a characteristic photonic energy from an element of interest for which a fluidic concentration is to be measured by said method;
• and
• freedom from any single contaminant in excess of 1 part per million, when measured by x-ray fluorescence.

A method of optimizing fabrication of an ionic preconcentration cell for identifying and measuring concentrations of elements in fluids;

• said ionic preconcentration cell comprising an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof;
• and a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• said method comprising the step of:
• optimizing said upper high surface area electrode with an upper electrode thickness less than or equal to approximately an optical depth l of said upper high surface area electrode when wetted with a fluid to be flowed through said cell.

A method of optimizing fabrication of an ionic preconcentration cell for identifying and measuring concentrations of elements in fluids;

• said ionic preconcentration cell comprising an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof;
• and a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• said method comprising the step of:
• optimizing said upper high surface area electrode with an upper electrode thickness less than or equal to approximately an optical depth l of said upper high surface area electrode when wetted with an element of interest for which a fluidic concentration is to be measured by said cell, in a fluid to be flowed through said cell.

A method of optimizing fabrication of an ionic preconcentration cell for identifying and measuring concentrations of elements in fluids;

• said ionic preconcentration cell comprising an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof;
• and a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• said method comprising the step of:
• optimizing said central flow interelectrode gap having said predetermined interelectrode gap width, designated d, within an interelectrode gap range specified by:
• d
• =
• σΦ
• q
• ⁢
• ⁢
• ɛ
• ⁢
• w
• i
• w
• f
• ⁢
• A
• n
• f
• ⁢
• CF
• ×
• 100
• ⁢
• %
• ≈
• 2
• ×
• 10
• -
• 9
• ⁢
• Φ
• ⁢
• ⁢
• w
• i
• ⁢
• A
• q
• ⁢
• ⁢
• ɛ
• ⁢
• ⁢
• w
• f
• ⁢
• n
• f
• ⁢
• F
• ×
• 100
• ⁢
• %
• ∝
• Φ
• ⁢
• ⁢
• A
• ɛ
• ⁢
• ⁢
• F
• ;
• wherein:
• ε designates a predetermined percentage of at least one element of interest to be extracted from a fluid to be flowed through said cell, σ designates a composite conductivity of said fluid, Φ designates a voltage differential applied across said electrodes, q=1.60×10−19 Coulomb designates the unit charge, A designates an ordinary surface area covered by said electrodes, nf designates a number density of said fluid, wi and wf designate atomic/molecular weights, respectively, of said at least one element of interest and of said fluid, c designates a concentration of said at least one element of interest in said fluid, and F designates a flow rate of said fluid through said ionic preconcentration cell;
• said high surface area electrodes further having said ordinary surface area A approximately equal to an interrogation spot area of x-rays to which said preconcentration cell is to be exposed;
• said ε is chosen to be below approximately 5% for said at least one element of interest;
• said Φ is chosen to be below an electrochemical potential of said at least one element of interest and below an electrolysis potential of said fluid;
• said F is chosen to exert no more than approximately 0.1 atm of pressure upon an upper x-ray transmission window of said ionic preconcentration cell in intimate contact with an upper surface of said upper high surface area electrode;
• said nf and said wf are chosen with reference to said at least one element of interest;
• and
• said wi is chosen with reference to said fluid.

An ionic preconcentration cell apparatus for identifying and measuring concentrations of elements in fluids, comprising:

• an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof, substantially parallel to said upper high surface area electrode;
• a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• fluid flow means for flowing a fluid through said central flow interelectrode gap;
• and
• flow control means for controlling a flow rate of said fluid through said ionic preconcentration cell so as to maintain ε, which designates a predetermined percentage of at least one element of interest to be extracted from said fluid, below approximately 5% for said at least one element of interest.

A method for identifying and measuring concentrations of elements in fluids, comprising the steps of:

• flowing a fluid through a central flow interelectrode gap of an ionic preconcentration cell separating an upper high specific surface area electrode from a lower high specific surface area electrode of said ionic preconcentration cell by a predetermined interelectrode gap width;
• applying a voltage differential between said upper high surface area electrode and said lower high surface area electrode while said fluid is flowing through said central flow interelectrode gap;
• exposing said cell to x-rays;
• deducing an identity, or measurement of concentration, of at least one element in said fluid based on a response of said preconcentration cell to said x-rays;
• and
• controlling a flow rate of said fluid through said ionic preconcentration cell so as to maintain ε, which designates a predetermined percentage of at least one element of interest to be extracted from said fluid, below approximately 5% for said at least one element of interest.

An ionic preconcentration cell apparatus for identifying and measuring concentrations of elements in fluids, comprising:

• an upper high surface area electrode having a high specific surface area thereof;
• a lower high surface area electrode having a high specific surface area thereof, substantially parallel to said upper high surface area electrode;
• a central flow interelectrode gap separating said upper and lower high surface area electrodes by a predetermined interelectrode gap width;
• fluid flow means for flowing a fluid through said central flow interelectrode gap;
• and
• time control means for controlling how long said fluid flows through said ionic preconcentration cell based on setting an impurity concentration C, in a range where conductivity varies substantially linearly with concentration, to a predetermined desired concentration detection level and flowing said fluid for a time t given by:
• t
• ∝
• Sl
• σ
• ∝
• Sl
• C
• ,
• S designates a sensitivity of x-ray detection equipment to be used for said detecting and measuring;
• l designates a thickness of said upper high surface area electrode;
• and
• σ designates a composite conductivity of said fluid.

A method for identifying and measuring concentrations of elements in fluids, comprising the steps of:

• flowing a fluid through a central flow interelectrode gap of an ionic preconcentration cell separating an upper high specific surface area electrode from a lower high specific surface area electrode of said ionic preconcentration cell by a predetermined interelectrode gap width;
• applying a voltage differential between said upper high surface area electrode and said lower high surface area electrode while said fluid is flowing through said central flow interelectrode gap;
• exposing said cell to x-rays;
• deducing an identity, or measurement of concentration, of at least one element in said fluid based on a response of said preconcentration cell to said x-rays;
• setting an impurity concentration C, in a range where conductivity varies substantially linearly with concentration, to a predetermined desired concentration detection level;
• and
• controlling how long said fluid flows through said ionic preconcentration cell by flowing said fluid for a time t given by:
• t
• ∝
• Sl
• σ
• ∝
• Sl
• C
• ,
• wherein:
• S designates a sensitivity of x-ray detection equipment to be used for said identifying and measuring;
• l designates a thickness of said upper high surface area electrode;
• and
• σ designates a composite conductivity of said fluid.