User manual

Bio-inert Quaternary Pump User Manual 57

Optimizing Performance

Operational Hints for the Multi Channel Gradient Valve (MCGV)

In a mixture of salt solutions and organic solvent the salt solution might be

well dissolved in the organic solvent without showing precipitations. However

in the mixing point of the gradient valve, at the boundary between the two

solvents, micro precipitation is possible. Gravity forces the salt particles to fall

down. Normally the A channel of the valve is used for the aqueous/salt

solution and the B channel of the pump is used for the organic solvent. If used

in this configuration the salt will fall back into the aqueous solution and will

be dissolved. When using the pump in a different configuration (e.g., D - salt

solution, A - organic solvent) the salt can fall into the port of the organic

solvent and may lead to performance problems.

NOTE

When using salt solutions and organic solvents it is recommended to connect the salt

solution to one of the bottom ports of the MCGV and the organic solvent to one of the upper

gradient valve ports. It is best to have the organic channel directly above the salt solution

channel. Regular flushing with water of all MCGV channels is recommended to remove all

possible salt deposits in the valve ports.