Patent ID: 9389261
Filing Date: 2016-07-12
CPC Classification: B01D,G01N,G01R

Claim Text:
1. An apparatus for measuring a net charge density of a membrane, comprising: a membrane permeation measurement module, comprising a chamber, two electrodes disposed in the chamber, a target membrane to be measured, and a solution, for measuring permeation rate caused by a pressure difference ΔP between two surfaces of the target membrane and electroosmotic volumetric flow rate caused by an electric field applying across the target membrane; a pressure measurement module, for measuring the mechanical pressure difference ΔP between the two surfaces of the target membrane; and a streaming potential measurement module, for measuring the streaming potential Ē across the target membrane; and a control module, for controlling measurement procedures and collecting data from each module to calculate the net charge density ρ where ∈k wherein the product of the porosity ∈ and average electrical conductivity k