Method and apparatus for in-situ spectroscopic analysis

An apparatus for in-situ analysis of a flowable material, comprising:

• a flow cell having a flow passage and means for introducing said flowable material into said flow passage for flowing therethrough, said flow cell including a cell chamber in communication with said flow passage, said cell chamber including a region of reasonable flow;
• said flow cell further including a first probe means bore having a first probe seat disposed proximate one end thereof and a second probe means bore having a second probe seat disposed proximate one end thereof;
• first probe means for transmitting the light of a given wavelength into said cell chamber, said first probe means having first optic means in communication with said region of reasonable flow, said first probe means being supported in said first probe means bore and adapted to engage said first probe seat;
• second probe means for detecting emission light from said flowable material, said second probe means having second optic means in communication with said region of reasonable flow, said second probe means being supported in said second probe means bore and adapted to engage said second probe seat;
• said first and second probe means having a path length in the range of approximately 1 μm to 10 mm;
• and
• control means in communication with said first and second probe means for providing said light to said first probe means and analyzing said emission light detected by said second probe means.

A method for in-situ analysis of a flowable material having a plurality of constituents, comprising the steps of:

• introducing a first material into a flow cell, said flow cell having a cell chamber in communication with said flow passage, said cell chamber including a region of reasonable flow, first probe means for transmitting light of a given wavelength into said cell chamber, said first probe means having first optic means in communication with said region of reasonable flow, second probe means for detecting emission light from said flowable material, said second probe means having second optic means in communication with said region of reasonable flow, said first and second probe means having a path length in the range of approximately 1 μm to 10 mm;
• measuring the absorption spectrum of said first material to obtain a transmitted energy spectrum by passing a given wavelength of light through said first material;
• introducing a second material into said flow cell;
• measuring the absorption spectrum of said second material by passing a given wavelength of light through said second material;
• determining the effective flow path length (Pfc) by the following relationship,
• Pfc=Pc×Afc/Ac
• where:
• Pc=Path length of cuvette
• Afc=Absorbance of potassium dichromate in the flow cell.
• Ac=Absorbance of potassium dichromate in the cuvette;
• introducing said flowable material into said flow cell;
• measuring the absorption spectrum of said flowable material by passing a given wavelength of light through said flowable material;
• confirming the presence of at least one constituent in said flowable material;
• and
• determining the concentration of at least one constituent in said flowable material.