Ion conductivity filter and measurement system

A method of measuring the cation conductivity of a fluid sample, the method comprising:

• flowing the fluid sample through an ion conductivity filter, comprising:
• flowing the fluid sample across a first cellulose filter disposed in a housing, wherein the first cellulose filter is disposed adjacent to an inlet to the ion conductivity filter, the inlet disposed at a first end of the housing;
• flowing the fluid sample from the first cellulose filter across a cation exchange resin filter disposed in the housing;
• and
• flowing the fluid sample from the cation exchange resin filter across a second cellulose filter disposed in the housing, wherein the second cellulose filter is disposed adjacent to an outlet from the ion conductivity filter, the outlet disposed at a second end of the housing, the second end opposite the first end;
• and
• providing an effluent from the outlet of the ion conductivity filter to a cation conductivity sensor configured to measure a cation conductivity of the effluent.

A method of making an apparatus for measuring the cation conductivity of a fluid sample, the method comprising:

• disposing a first cellulose filter in the interior of a housing adjacent to an inlet disposed at a first end of the housing;
• disposing a cation exchange resin filter in the interior of the housing adjacent to the first cellulose filter;
• and
• disposing a second cellulose filter in the interior of the housing adjacent to the cation exchange resin filter and adjacent to an outlet disposed at a second end of the housing, the second end opposite the first end,
• wherein the outlet is configured to be fluidically connected to a cation conductivity sensor configured to measure a cation conductivity of an effluent output from the outlet.