Apparatus to determine zero charge point of colloids and suspensions

摘要

Apparatus to determine the zero charge point of electrically- charged colloids and/or suspended particles in a fluid comprises an electrophoresis cell (1), a dosing meter, a measuring device and a data analyser. The fluid under investigation flows through the cell, where an electrostatic field is applied to the particles in the suspension. The dosing meter adds a charge-neutralising medium. The measuring device (9-16) determines alteration of particle density with time, preferably taken locally, in the fluid within the cell. The data processor (12) records this density variation as a function of neutraliser dosed, up to the point where it approaches zero. The remaining quantity of neutraliser needed to complete the neutralisation is extrapolated.