In general, there are several common faults in the operation of the ion chromatograph. The chemical experimenter must learn some simple peacekeeping operations of the ion chromatograph.

One, from the mobile phase to the pump between the air bubbles, how to rule out?

The exclusion method is as follows: First, the plastic flow channel connector connected with the pump is screwed off, the deionized water is filled with the ear syringe, and injected from the flow channel tube connected with the pump segment, and the air bubbles in the flow channel tube are eliminated. Then raise the mobile phase bottle (usually a deionized water bottle) and connect the flow line connector to the pump. Start the pump, open the pump exhaust valve selection button, remove the air bubbles in the pump, generally observed as a more uniform effluent, and then tighten the pump exhaust valve. (Note: In this operation, the entire flow path is disconnected from the column)

Second, the pump check valve plug what phenomenon? How to operate?

If the pump check valve sticks with microorganisms and clogging can cause the pump to fail, the most obvious phenomenon is that there is no liquid flowing out of the waste pipe or the pump is started or the solution is flowing out slowly.

If the check valve is blocked, we need to clean it. The cleaning method is as follows:

First unscrew the flow-through connector and connector 1, and then unscrew the left-side connector 2. Use a tweezers to remove the two-way check valve into a 50-ml beaker. (When taking out, observe the direction of the arrow on the check valve. In the same way), adding a small amount of absolute ethanol just over the two one-way valves. Then put it in the ultrasonic cleaner for 30-60min. After cleaning the check valve with water, install the check valve in the reverse direction. (Note: do not tighten the connector too tightly so as to avoid damage to the screw pattern)

Third, suppressor current no display, how to determine the problem? How to operate?

a. First understand the structure of the suppressor:

b. Checking the suppressor circuit: Unscrew the four corners of the suppressor box with a screwdriver and you can see the suppressor diagram shown in Figure 3. Remove the electrode lines on both sides of the suppressor. Note that the color of the electrode lines on both sides is not consistent (usually the red line is on the right side, and the left side is gray or black line). Connect the two electrode lines with the analog resistor (100 ohms) in the accessory kit. , Turn on and adjust the current knob on the control panel clockwise to observe the change of the current display number on the touch screen. If the change rule is adjustable from 45-100 or 105mA, indicating that the suppressor circuit is operating normally, then the cause of the abnormal display of the suppressor current is due to a bad contact when the two electrode wires are connected to the suppressor. If there is no change, it is always displayed as 0, indicating that the suppressor circuit has been punctured and the circuit needs to be replaced or maintained.

c. Flanging and connection of the four-way flow connector on the suppressor: The connection of the connector from the outlet of the conductivity cell needs to be turned over when it enters the suppressor again.

d. Connection of suppressor fittings and maintenance of leakage problems: There are three main connectors on the suppressor, one is connected to the column outlet (PEEK taper joint), and the other two are connected to the conductivity cell inlet (PEEK taper joint) and Outlet (four-way flow connector), joints are marked on the suppressor, and be careful not to make mistakes when connecting. In addition, the connection of the joints should not be tight and should not leak. If the connector at the outlet of the column is tightened too tightly, the system pressure will increase. If the four-way flow connector at the outlet of the conductivity cell is tightened too tightly, the solution will not flow through the conductivity cell, and even worse, it will cause the ion exchange membrane of the suppressor to rupture and damage the suppressor.