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AL-208 Transfer Procedure

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AL-208 (Europe only)
UN-Pac Packing System and Transfer Procedure for Type C

Introduction / Specifications / Recommended Transfer Procedure / Equipment

Recommended Tranfer Procedure:

Refer to Figure 2 while following this procedure

Figure 2: Typical transfer system for UN-PacM Type C

Due to the hazardous nature of the products packaged in UN-Pac containers appropriate personal protective equipment must be worn throughout the entire transfer procedure. Read all steps before starting and do not work alone. This procedure must only be performed by technically qualified individuals.

Step 1
Place the UN-Pac container in a secure and upright position in a safe and well ventilated area. If the product is to be delivered by weight, secure the container on a floor scale. Ground the container using an appropriate grounding strap (Z150304).

Step 2
Make sure the liquid outlet valve A is closed to the diptube by turning handle B (red cap) clockwise.

Step 3
Make sure the nitrogen inlet/vent valve C is closed by turning the handle D (green Cap) clockwise.

Step 4
Carefully remove plug F from the nitrogen inlet/vent valve C. Save this plug for later replacement. The plug is fastened on a warp shown in Figure 3.

Figure 3: Valve

Step 5
Connect a nitrogen-inlet adapter G to a suitable nitrogen source using flexible plastic tubing. Adapter G (shown in Figure 6) is supplied in a plastic bag with the cylinder. Secure the tubing in place. The nitrogen should be pressure-regulated at 0,4-0,7 bar.

Step 6
Adjust the nitrogen source to give a slow stream exiting from nitrogen inlet adapter G and connect to the nitrogen inlet/valve C. See Figure 4b. Finally, check the connections for absence of leaks using Snoop (Z273910) or a water/soap solution.

Figure 4a Figure 4b Figure 4c

Step 7
Slowly and carefully remove plug E from the liquid outlet port of liquid outlet valve A. Save this plug for later replacement. The plug is fastened on a warp shown in Figure 2.


Occasionally there may be liquid or solid under the plugs and some fuming may occur with the more reactive reagents. Without operating the valve, remove any solid from the valve opening by washing with a stream of odorless mineral spirits from a wash bottle, and use a wire brush to clean the threads if necessary. Wear appropriate protective equipment.

Step 8
Prepare a liquid-transfer line that is clean and dry. Exchange the outlet the container. Remove the outlet adapter P from the transfer line. Insert the male tube adapter (1/4 NPT) of assembly H into the transfer line (See Figure 6). Wrap Teflon-tape (Cataloge No. Z104388 or Z148814) around the threads.

Figure 5:
Transfer Line with Adapter (P)
The complete list of available transfer lines is given in Table 2 with a representative system shown in Figure 7. Technical Information Bulletin No. AL-150 gives a complete list of available needles for these transfer lines.

Step 9
Open ball valve J and needle valve K and insert needle L into a septum on nitrogen-flushing adapter M, which is easily prepared by putting septa (sleeve stoppers) on both ends of a short piece of glass, plastic or metal tubing (See Figure 2). We recommend using our septum (Catalog No. Z124370) on each end of a 6-inch length of 14-mm ID glass or 3/8 –inch ID polyethylene, polypropylene or stainless steel tubing.

Step 10
The flow through nitrogen-flushing needle N is adjusted to give a fast exit stream, then N is inserted in the other septum on M. Please consult Aldrich Technical Information Bulletin No. AL-134 for a complete description of the use of septa and needles in handling air-sensitve reagents.

Step 11
Connect the female part of assembly H to the liquid-transfer line. This assembly H (shown in Figure 5) is then attached to the liquid outlet valve A (G1/4 Zoll) with the other side of adapter (R1/4 Zoll). Tighten the nut (back up wrench) on the adapter as shown on the bag container of adapter and Figure 5a. Use two wrenches when tightening.

Figure 6: Assemby H (bottom 2 pieces) &
Adapter G

Figure 6a: Ferrule Lock Nut Tightening Asemby

Note: Always use two wrenches: one to hold the tube fitting body while using the other to tighten the nut

Step 12
The nitrogen stream is now exiting through septum inlet Q. At this point install septum R (Catalog No. Z100722 or Z124354) to inlet Q and wire in place.

Step 13
Check all connections in entire transfer line for absence of leaks using a Snoop or a water/soap solution.

Step 14
Remove nitrogen-flushing needle N from adapter M and insert into septum R On inlet Q.

Step 15
Remove adapter M from needle L and nitrogen will exit from the end of needle

Step 16
Insert needle L into septum S on septum-inlet adapter T which is on a clean, dry, nitrogen-flushed receiver or reaction apparatus. Push needle L into the system until the end of the needle is beyond any fitting between the reaction apparatus and adapter T (Note: The reaction apparatus or receiver should have been flushed previously with nitrogen and connected to a mineral oil bubbler).

Step 17
Needle valve K can now be turned off and nitrogen-flushing needle N can be removed from septum R or inlet Q.

Step 18
Cautiously open handle B (turn counter-clockwise) on valve A and watch the end of needle L and the level of mineral oil in the exit bubbler from the reaction apparatus. If liquid flow is not observed from needle L soon or if the oil level rises (suck- back) in the center tube of the mineral oil bubbler, immediately turn off valve A (turn handle B clockwise) and proceed to Step 19. If flow is noted, go to Step 20.

Step 19
Cautiously open handle D (turn counter-clockwise) on valve C. This will pressurize the vapor space in the cylinder to 0,4-0,7bar of nitrogen. Return to Step 18.

Step 20
When the desired amount of liquid has been transferred, close outlet valve A and ball valve J; then close inlet valve C (if open). During the actual transfer of liquid, inlet valve C can be opened and closed as needed to maintain a reasonable flow of product from needle L. If necessary, the nitrogen pressure can be increased up to 2 bar to increase the rate of flow.

Step 21
Needle L can be removed from septum S and placed in a new septum on another reaction apparatus, or it can be removed from septum S and placed in an adapter M for short-term storage (less than a few hours). For long-term storage (more than a few hours) or when the container is empty, the transfer apparatus should be removed from the container as described in Steps 22-31.

Step 22
With needle L still in the reaction apparatus or inserted in a septum on a suitable receiver, open ball valve J and insert nitrogen-flushing needle N into Septum R.

Step 23
Open needle valve K to flush residual liquid from the transfer line.

Step 24
Close needle valve K followed by ball valve J and remove needle L from the receiver and place into the septum on adapter M.

Step 25
Check to make sure that inlet valve C is closed; then remove adapter G and replace plug F.

Step 26
Check to make sure outlet valve A is closed; then remove adapter assembly H (turn clockwise to remove).


A small amount of liquid will remain behind adapter assembly H in the valve opening. If the reagent is highly reactive with air some fuming may result. It is necessary to cap the open ends as mentioned immediately to prevent excessive reactivity.

Step 27
Once removed from the container, place the transfer line in an empty metal bucket and carry to a safe distance from the container.

Step 28Return to the cylinder. Rinse the inside of the valve opening with a stream of odorless mineral spirits (Catalog No. Z262560) from a wash bottle. Clean the threads, if necessary, using a small wire brush to remove any solid.

Step 29
If necessary, clean the threads on plug E in a similar fashion, then wrap Teflon tape around the threads only. This is not done to improve the seal but to aid in later removal of the plug.

Step 30
Replace plug E in valve A and tighten using a adjustable wrench.


Do not open the cleaning hole in the middle of the top. The hole is closed with a 2 zoll stainless steel snatch with a gasket and saved with a Tri-Sure cap.

Step 31
Remove any chemical residue from the exterior of the container.


Do not mark directly on or place additional labels on the UN-Pac containers. Use tags or place labels on the on the plastic sleeve to label as partial or empty .

Failure to remove chemical residue from exterior can result in damage to the container and may lead to loss of the deposit.

Step 32
The UN-Pac container can now be returned to storage or shipped back to Aldrich. The transfer apparatus should be cleaned as described in Steps 33-36.

Step 33
If a pure solvent was handled, then the transfer line can be brought inside and cleaned via normal procedures for laboratory apparatus. If a highly reactive reagent was handled, the transfer line is left outdoors with adapter M and septum R removed and needle valve K and ball valve J open.

Step 34
While still outdoors, rinse the line with a stream of odorless mineral spirits into an empty metal bucket. Caution: If the product is phoric, this sometimes results in a fire. (Note: The transfer line should be rinsed as soon as possible after it is removed from the container. If this is not done, partially hydrolyzed material will often plug the ends of the inner material remains active. This can cause problems when the transfer line is eventually cleaned.)

Step 35
After the rinse with odorless mineral spirits, flush the line with water, dilute acid (if needed to dissolve solids formed on hydrolysis), water and finally acetone or methanol.

Step 36
The transfer line can be brought inside for a final clean-up following normal procedure for laboratory apparatus.

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This information is presented to assist you in evaluating our product. It is intended for use by technically-skiIled persons. We do not guarantee favorable results, and we assume no liability inconnection with its use. This information is not intended as a license to operate under, or arecommendation to infringe, any patent covering any material or use. Not for drug, food, cosmetic or household use.