Q’s & A’s from Our Customers
Q: From: A US solar energy company headquartered in Redwood City, California
I’m Interested in a 3-5 solvent drying cabinet mount system. (I only have 43" of width available.) Questions: (1) We have high purity house N2. Can this be used in place of Ar? (2) What are the ventilation requirements for these systems? Please advise.
A: Thanks for contacting us. To answer your questions, yes you can use High Purity N2 in place of Ar as long as it's from a liquid source (blow off from a dewar or liquid tank).
If you're all set with that then we could fit a five solvent system inside 43", I attached a drawing for you to look at. As for ventilation that's your choice, most just place the system in the lab, others do more. It's really a case by case basis depending on EH&S requirements.
If that all looks good, let me know which solvents you want in the system and I can send a quote over.
Q: We have been using PPT SPS for around 5 years and it performs really well. It consists of six solvents including Pentane and recently we noticed an issue with the pentane line.
Solvent (pentane) does not come out even if the keg is full. Only less than 50 mL can be collected at a time. We are not sure whether the problem is with the column or the line. We would be grateful if you could provide us some assistance in this matter. The filter is clean. Pentane column has never been replaced before.
A: Thank you for contacting PPT concerning your solvent question. You can try a few things. First I would need to know what pressure the Argon Gas is set to? Ideally, you want that between 8-12psi, I recommend running the system at 10psi.
You can also try removing the flask and using a beaker. Place it beneath where the flask goes and open the solvent valve. Solvent should flow freely into the beaker.
If you do not get good flow, try removing the tubing above the filter, but first you need to close the valve on the column. Then try flowing solvent through the tubing above the filter.
Q: Our lab has a glass contour solvent system and four solvents purification systems inside (THF/ Tetrahydrofuran, toluene, dichloromethane, and DMF/ Dimethylformamide).
1. We have used this system for 5 years and just wonder if it is necessary to change the columns?
2. We do not know how long the columns can be used to dry solvents normally. Does PPT carry replacement columns that will fit our solvent system?
3. Also, we normally fill the solvent kegs with anhydrous solvents for best system performance, but is it possible to fill the kegs with lower grade solvents?
A: PPT's response to the question about this 4 column system:
1. We recommend changing columns after 4-5 years; typically that's the life span of columns for a lab with average use. The other way is to test for water with a Karl Fisher Titrator but most labs do not have access to those.
2. Yes our columns fit both glass contour and PPT systems.
3. Using HPLC or ACS grade solvent is recommended for filling columns, anhydrous solvent is much more expensive and not necessary.
Q: I am writing to you in regards to a SPS system installed in the Department of Drug Design and Pharmacology at University of Copenhagen. As far as I know the system was installed in 2011 and it’s been running on originally supplied columns since then.
1. I would like to ask whether the columns should be replaced with new ones? We don’t have easy access to KF titration to measure the water content. Estimated amounts of solvents that passed through the columns since 2011 are: THF-150 liters; DCM-170 liters and DM-130 liters
2. Please also indicate if there is a local representative we can get in touch with in order to purchase new columns and reservoirs?
A: PPT's response to this 2-part question about the system installed in 2011:
1. Generally we recommend changing columns every four to five years but based on your usage above you have not used a lot of solvent. On a volume basis the capacity ranges between 600 - 800 liters of capacity. I would say you are probably fine for now however without testing, it's difficult to know how exactly the columns are performing. If your reactions are looking good and you’re not seeing any unusual results I would say run them for another year and then think about changing them. My recommendations are, of course, based on proper use and proper quality of solvents through the system.
2. Feel free to contact our office for prompt processing of replacement columns when you are ready.
Q: We have a Glass Contour solvent system and are planning to move it into another location as part of a building process. Our hope is that we can disconnect the solvent kegs, close the valves for the columns, and move the system in one piece to make the setup process as simple as possible. I wanted to check to see whether there are any special considerations we should note as we plan for this move.
A: The easiest way would be to strap the Solvent Cabinet up to the frame lifting it off the floor. Use casters under each leg of the frame to roll it to its new location. This way you do not have to disconnect anything, we've done this many times and can lend you the casters if needed. This only works if you are moving it between rooms or buildings close by. Feel free to call me at your convenience to discuss your particular circumstances further.