Your buddy may display a legitimate facility and social reason… still maybe he was too sloppy on the intended use of the product. When you purchase such compounds, even at research scale, they often ask you to provide a very short description of the intended use (and precise to not simply indicate “research”…). At this point, one should be honest. I believe those people are trained to decipher what’s legitimate or not (they have a list of commonly known uses…), and are also in some case required to forward the request to specific authorities.
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Absolutely… i think one of the main reasons he was denied because it was being purchased with a personal account and credit card and didn’t end up using a business card. the billing address given was a residential address so they couldn’t proceed with the order unless he chose to pay with it from a business card… who knows. It is likely that the group was pretty vague about their usages for the catalyst so it’s makes sense really…
For safe anaerobic work, better use either use overpressurized gloveboxes with constant gaz circulation, or glovebags with N2/H2 atmosphere and palladium scrubbers. Second option is cheaper, and much more flexible (much quicker to condition, or to remediate in case of sudden air entry…).
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And I tell you, you could be legitimate on every required point, and still get troubles getting the product. Because this also eventually depends on the local political agenda, and/or where the local racism is aimed to…
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We’ll see how it goes, my current plan is to run constant N2, I’ve got an O2 meter and disposable oxygen/moisture absorbers to help everything dry and inert 
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Yust buy it as a 1 mol solution in heptane or hexane and it is wayyyyy less reactive
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Typically one wouldn’t consider using triisobutylaluminium or any of the other pyrophoric catalysts to yield d8. They yield far greater levels of d9 to be of any use for that application.
It’s true that Sigma/Alfa won’t ship triisobutylaluminium to just anyone with a lab. This is definitely a good thing. We don’t want people ordering such things on a whim. Stay safe everyone
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Well it will cost quite a certain volume of N2 to first condition the boxes, and further keep it anaerobic over days… and this approach normally requires to be constantly over-pressurized (with the glove hanging out when unused.). It needs a constant gas supply, and some pressure regulation systems. In fact you got to constantly push out the O2 which eventually enters the glovebox…
The system using H2 and Pd is more passive. It consist in constantly scrubbing the O2 that enters (there is always some .ppm) in situ by reacting with the excess H2 to form water. Working so, doesn’t need to work under pressure (still needs good air-tightness). In addition, the advantages of using a bag is that you need much less gas to condition it (you can partly inflate and deflate it like a lung), it takes also much less time to do so. And it’s size also adapt to the pressure difference with outside…
And what kind of O2 sensor do you have ? what ranges does it measure ?
The one you would normally need for this purpose are not linear over a large range, and does not work properly if O2 concentration is above 2000 ppm. Ambiant atmopshere is 100 times above this, and what you want to reach is rather a 1000 time below (below 2 ppm ideally).
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Yeah it was originally you who I was working with helping us out in that endeavor but my guy could never get it ordered. Even though there wasn’t a house within a 5plus mile radius of the lab they wouldn’t process the order due to the residual billing address on the card.
Thankfully I have the generator, primarily for the GC bit it definitely has other uses
Certainly not the most accurate, Amazon.com.
My goal is as dry and inert as is reasonably possible for the handful of times I’ll be using it. I’d be interested in learning more about the h2/palladium setup if it’s not too cost prohibitive as I do also have the H2 generator and i mean… why not?
In terms of gas needs, the N2/H2 approach is much more interesting. The H2 level inside got to be below the lower explosivity limit (<8%), Ideally between 2 and 5%. You can buy a bottle at 8%, and blend in situ with pure n2… eg you first fill with n2 and then change for the H2 mix. Then you need to stay in the 1-5% range for the rest of the time. The level of H2 will slowly decrease over weeks as it reacts with trace O2. If unused, you need to refresh the air only every 2 month or so . A big mix gas cylinder lasts for months and months.
With the other approach, it rather cost a cylinder per week… the generator must be able to keep up.
You would thus need a much more sensitive 02 sensor, that one here is made for ambiant conditions. Ideally, you would need one that measure O2 in the ppm levels, and also H2 at % levels.
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How does the palladium factor in?
Let me clarify: how do you use the palladium in this setup to the desired effect.
I understand it reacts to form water
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Here is a glimpse into the system I’ve been using for the last 6 years.
You can see the sensor. And in the middle left a part of one scrubber can be seen. It simply a box with a fan blowing ambient air on cage containing Pd/Al pellets. The reaction occur at their surfaces, and produces some heat and water. The catalyst need to be sometimes regenerated by drying it in an oven… very simple and highly reliable.
Before that, I was used to Braun or Jacomex fancy and expensive systems. It is like comparing a Rolls Royce and a Jeep. I preffer the Jeep way more.
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Please post more pix of ur lab @Dr_Jebril super interesting!
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Where might I find one of those handy dandy meters? Or, more appropriately, the term? I found a coy cam-12 “aerobic monitor” but cannot seem to find it available anywhere.
I did some back of the napkin math and over-estimated the volume of the box; at 500ml/min it will take 26 hours to conditions that volume of space; so, it’s just gonna run for a while
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Looks like they make monitors for weld purging that you might find appropriate. This one’s $2800 (yeah, fuck that lol) but it might suggest some search terms:
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Use the ebayfoo Luke!:
Yes this is a pricey sensor.
And better buy a new one, so you sure it is well calibrated.
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