High pressure mixer

The mixing chamber by SunChrom has been developed after extensive tests and long operation at wave lengths up to 190 nm. It is assembled on a stainless steel casing that is protected against splash water. The 3 solvent inlets are incorporated directly in the casing to reach, already at the entrance in the mixing chamber, a premix through the optimised geometry. This enables essentially improved mixing results. Many years of experience with diverse HPLC systems have shown that despite thorough handling of the solvents and of the single components, a certain abrasion of the pistons in the pumps and of the stirrer in the mixing chamber is inevitable. That is the reason why the different chambers are equiped with filter sieves with a mesh size of approx. 3 µm. They hold back the solid parts (abrasion, dust, etc.) from the column and the injection system because otherwise the column could clog and the selectivity could be modified.

The mixing part consists of 4 segments. The bottom part in-cludes the 3 connections for up to 3 pumps. The Teflon coated stirrer is located here. The rotation provides, with 500 min-1, a quickest mixing. Higher rotations are not possible because of the high viscosity of a lot of solvent mixtures such as methanol/water. Since the stirrer in the mixing chamber is actuated by a solenoid coupling, it would not rotate steadily any more. The intermediate ring acts as compensation or buffer vessel of the dynamic mixing part.