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Inline filters (6.2821.130) must be replaced every three months. The same applies for the coupling (6.2744.180).

Caution! The filter must not be damaged during insertion.

The stator and rotor can be removed using a 9/64 hexagon key (not included in the normal scope of delivery of the instruments). Both parts are cleaned with 20% methanol in an ultrasonic bath for 10 minutes.

iColumn features:

• Automatic recognition by the MagIC Net software
• All column data immediately available (max. permitted pressure, max. measured pressure, max. permitted flow, max. measured flow, hours of operation, number of injections, etc.)
• Active monitoring of all important column functions
• Traceability of all column parameters

Additional practical tips can be found in the column catalog:

Brochure: The column program 2021 (8.000.5347, PDF, 13 MB)

The old column with a guard column or built-in coupling must be removed first. The guard column and column can then be installed in stages. Inbetween, the eluent should be pumped for a few minutes.

The entire IC system is started by pressing Start HW. The system must be checked for leak-tightness. Once the baseline is stable, determinations can be started.

The filter and frit (6.1011.130) built into the guard column should be replaced if there is a sharp rise in pressure or at least every 4 weeks. Take into account that the filter and frit are mounted planar.

For additional details, download:

Leaflet for 6.1011.030 METROSEP RP 2 Guard (8.107.1246, PDF, 111 KB)

The hardware is stopped in MagIC Net. Once the pressure has fallen to 0 MPa and the column and guard column have reached room temperature, both can be removed from the system.

The optimum storage conditions for the column can be found in the leaflet of the column. Columns are generally stored in eluent. A coupling (6.2744.040) is necessary to connect the capillaries.

It is recommended that the piston and cylinder of the dosing unit be checked regularly (e.g., semi-annually). The cylinder must always be emptied before the dosing unit is opened. The Empty command in the Manual window in MagIC Net can be used to do this. Afterwards, all of the tubings and the adsorber tube must be removed. Replacement of the inline filters is recommended in addition to the cleaning of the buret, when a buret is used for Dosino Regeneration.

The condition of the cylinder and piston can now be checked. The glass cylinder should not exhibit any corrosion. The plastic cover (PTFE) of the piston may not be damaged in any way. The piston can be removed using the piston pliers 6.1546.030.

Caution! Never separate the cylinder from the cylinder bottom.

All parts can now be cleaned. Do not use scouring agents! Allow to air dry.

If parts stick to one another, do not use force to separate them. Do not place parts in an ultrasonic bath. Place the dosing unit in ultrapure water for a few minutes. Very carefully try to loosen the parts by hand (without twisting).

The centering tube and housing are lubricated on their sliding surfaces with paraffin oil (6.2803.010).

Caution! The dosing cylinder and piston, especially their sealing lips, must not be damaged during assembly.

The piston stopper must be flush with the upper edge of the housing. To accomplish this, press the entire dosing unit head first on a tabletop. Then check whether the marking triangles are aligned. Turn to align the marking triangles, if necessary.

If the dosing unit is used on a bottle, then it is recommended that the adsorber tube be used on the Vent connector. The soda lime in the adsorber tube should be replaced twice a year. (Soda lime pellets with indicator, Merck 1.06839.1000)

The dialysis membrane and the filtration membrane must be checked regularly and replaced as necessary. A decreasing recovery rate when analyzing check standard solutions can serve as an indicator. It is recommended that the check standards are measured after every fifth to tenth sample. The cells can be opened with a 5 mm hexagon key (6.2621.070).

The dialysis or ultrafiltration cell can be cleaned with ultrapure water or, if necessary, with a 30:70 mixture of ethanol and water. Other organic solvents, e.g. acetone, will damage the Plexiglas cell. The cell can then be dried with a lint-free cloth.

A new dialysis or ultrafiltration membrane can be conditioned using the tweezers (6.2831.010) in a Petri dish filled with ultrapure water (approx. 2 min). The light blue separation paper has to be removed. The screws have to be tighened diagonally.

6.2714.010 Dialysis membrane (cellulose)

6.2714.030 Dialysis membrane (polyamide)

6.2714.020 Ultrafiltration membrane

Only PVDF pressure screws (6.2744.000) may be used for the capillary connections. Using PEEK pressure screws may lead to stress cracks in the cell! The cell must then be checked for leak-tightness. Moreover, no air bubbles should get caught in the cell.

Peristaltic pump tubings wear out over time. It is recommended that the contact pressure is checked regularly and the position changed monthly. A peristaltic pump tubing should be replaced, if necessary. It is essential that the connector be installed with the filter (6.2744.180) on the pressure side. The peristaltic pump tubing must cover at least three grooves.

The hose clamps must be applied again after installation. To do this, the clamps must be tightened slowly until the liquid flows. Once the liquid is flowing, tighten the clamps two click tighter.

The inline filter (6.2821.130) on the peristaltic pump tubing should be replaced every three months, or more frequently in the case of increased back pressure.

If the MSM leaks, the unit must be disconnected and then cleaned. The surface of the rotor and connecting piece can be cleaned with ethanol using a lint-free cloth. Beware, the rotor must be built into the correct position as indicated. After it is reattached, the back pressure should be monitored. The system pressure (without a column, with a conductivity detector) with a flow of 1 mL/min should be as follows, depending on the setup:

• without suppression < 1.0 MPa
• with chemical suppression (MSM) < 1.5 MPa
• with sequential suppression (MSM/MCS) < 2.5 MPa

Proper tightening when fixing the connector is important. First tighten gently with a finger. Then tighten with somewhat more force (approx. 3/4 turn) until the end stop is reached.

If the so-called Dosino Regeneration is used, then the Inline Filter (6.2821.130) must be replaced every three months. Furthermore, the dosing unit must be checked and cleaned on a regular basis.

It is recommended that the piston and cylinder of the dosing unit be checked regularly (e.g., semi-annually). The cylinder must always be emptied before the dosing unit is opened. The Empty command in the Manual window in MagIC Net can be used for this purpose. Afterwards, all of the tubing connections must be removed.

The condition of the cylinder and piston can now be checked. The glass cylinder should not exhibit any corrosion. The plastic cover (PTFE) of the piston may not be damaged in any way. The piston can be removed using the 6.1546.030 piston pliers.

Caution! Never separate the cylinder from the cylinder bottom.

All of the parts can now be cleaned. Do not use scouring agents. Allow to air-dry.

If parts stick to one another, do not use force to separate them. Do not place parts in an ultrasonic bath. Place the dosing unit in ultrapure water for a few minutes. Afterwards, attempt to loosen the parts very carefully by hand (without twisting).

The centering tube and housing are lubricated on their sliding surfaces with paraffin oil (6.2803.010).

Caution! The dosing cylinder and piston, especially their sealing lips, must not be damaged during assembly.

The piston stopper must be flush with the upper edge of the housing. To accomplish this, press the entire dosing unit head first on a tabletop. Afterwards, check whether the marking triangles are aligned, rotating them if necessary to accomplish this.

The adsorber tube should be used for certain applications, e.g., "Inline Eluent Preparation". The soda lime in the adsorber tube should be replaced twice a year. (Soda lime pellets with indicator, Merck 1.06839.1000)

Depending on the application, barely visible deposits may build up on the lenses over time, which can lead to higher adsorption and therefore to a noisy baseline. If the interference is not being caused by other parts of the system, the flow-through cell must be cleaned. There are three ways to do this:

1. Rinse the flow-through cell with methanol
2. Rinse the flow-through cell with another solvent (e.g. acetic acid and isopropanol in a 1:2 ratio)
3. Disassemble the flow-through cell and clean it manually

In order to disassemble the flow-through cell and clean it manually, the seals (6.2764.000) must be replaced. Also necessary are a slotted screwdriver (size 5) and a lint-free cloth. Be careful when handling the lens in order to avoid scratches. The lenses on both sides of the flow-through cell have to be cleaned.

Caution! The flat side of the lens must face inward.

The complete measuring cell is inserted into the amperometric detector. All of the electrode cables and the inlet and outlet capillaries are connected.

Additional deaeration via the reference electrode chamber is to be recommended at the time of initial start-up and is particularly important when it is used with the glassy carbon working electrode.

The cell must be deaerated each time it is opened in order to ensure that it contains no air bubbles.

Caution! The measuring cell remains switched off during deaeration.

In the Manual Control of the software, the high-pressure pump is started with one-half of the standard flow of the column used. The temperature of the oven and the amperometric detector are activated afterwards. Any eluent that may escape is collected with a cloth.

In order to obtain good measuring results, we recommend that the front cover be mounted.

Caution!

• Do not pinch any capillaries. Use capillary feed-through.
• Do not pinch any cables.

The measuring cell can be switched on afterwards using startup hardware and the system can be equilibrated.

Depending on the application, the measuring cell can be operated with a variety of different spacers. The measuring cell must be disassembled with a 2.5 mm hex key for the replacement of the spacer. The new spacer should be dry and lint-free at the time of use. The cell can be reassembled afterwards.

6.1257.810 Spacer 50 µm to Wall-Jet cell

6.1257.820 Spacer 50 µm to Thin-Layer cell

6.1257.830 Spacer 25 µm to Wall-Jet cell

6.1257.840 Spacer 25 µm to Thin-Layer cell

Electrodes are consumables. Polishing can be used to restore the original electrode activity a few dozen times, if the electrode has not been too severely corroded. In addition to daily checking by wiping with a soft cloth, the following sequence is recommended for the mechanical cleaning:

1. With a pencil eraser: The electrode surface is treated carefully with a pencil eraser.
   
2. With aluminum oxide powder from the 6.2802.000 polishing set: The aluminum oxide powder in the 6.2802.000 polishing set is mixed with distilled water in such a way as to create a thick slurry. The electrode tip is polished in an octagonal movement for approximately 10 s. Rinse afterwards with distilled water. Activation with aluminum oxide powder is recommended at the time of initial start-up for both glassy carbon and platinum electrodes.
   
3. Creating a plane-parallel grind with the 6.2802.200 maintenance set: The 6.2802.200 maintenance set enables plane-parallel grinding of the corroded surface of metal electrodes. Wet-grinding of the working electrode is recommended. This prevents grinding dust from flying about. In addition, it is recommended that a separate grinding disk be used for each electrode material. A coarser grain is used for grinding in the initial step, followed then by a finer grain. The electrode should be inspected visually after every 4 revolutions. Repeat the procedure as needed. The electrode requires grinding with a fine disk after it has been ground with a coarse one. The electrode should be rotated by a one-quarter turn at least twice between the revolutions in order to obtain a uniform grind.

Leaflet on maintenance set for working electrodes 6.1257.2XX (8.110.8025, PDF, 197 KB)

In the video, a gold working electrode before (left) and after the cleaning (right). No visual differences are to be seen in the case of glassy carbon and Pt electrodes. Nevertheless, they should be cleaned when there is a loss in sensitivity.

The auxiliary electrode can be cleaned once the working electrode has been removed from the cell. In addition, it is essential that the reference electrode be removed in order to prevent the dissolution of the palladium oxide layer.

A soft paper towel or cotton swab is soaked in 2 mol/L nitric acid. The electrode is carefully wiped off. Afterwards, rinse the entire measuring cell with ultrapure water and dry it with a lint-free cloth.

Tip: If the cleaning with nitric acid is not sufficient, then the auxiliary electrode can be rubbed clean with a cotton swab soaked in aluminum slurry in a manner analogous to the use of nitric acid. To accomplish this, the cell must be disassembled and the electrodes and the spacer must be removed.

Learn how to clean the combustion tube of your combustion IC system step by step.