In 6 months we have had 3 different gas vendors. All failing for Benzene. Its getting worse in the last 2 months tho. After a month of almost all batches failing we ended up moving to SD and upon the first runs failed for 3x the allowable limits. SD is working to figure out what gas was sent to us altho I find it weird they dont know and have to look into it. Sounds like we have gotten gas from diversified and Cortera and both failed for benzene. Whats crazy is again before the whole cold crash medusa issue we never had any issues with benzene. All the distributors are pointing fingers and claim its cause some of their clients back fill the tanks with bad gas. We were supposed to have our own dedicated tanks from west air but after the fact they admitted that wasnt happening. Back in the day I would get the nastiest looking tanks and never had issues. Whats odd is alot of the tanks causing issues are like brand new tanks or very clean looking atleast.
Is anyone else out there having issues? I know my buddy down in San Diego is also having horrible issues with Benzene. We run a shit load of tanks every week so it does seem like we tend to be one of the first labs that see these kind of issues and it probably correlates to how much we run. Just wanted to give the community a heads up as this has caused so much streess and loss of $$.
I want to point out that gas goes fromt he white tanks through a dedicated media column with x13 and alumacel, then to a jacketed distilation chamber that we use to distill our gas before it enters the system. Curious to why the benzene isnt staying there. Also the Benzene only shows up in the Hte fraction when we are doing cold crashing and the thca is fine.
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Hey john,
At this point you should just get rid of that extra column with the x13 and alumacel and go straight to your distillation pot. Save a few bucks there if it’s not doing it’s job, unless you’re using it to prevent “Medusa”. Haven’t ran into this issue…yet! Sorry for your losses brother.
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It seems to help for when we get batches of gas that want to medusa. Doesn’t stop it all together but really does help minimize the frequency at which it pops up.
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how often are you swapping out that column? how many lbs of gas before your swap?
we do the same and find it does help, but would love to know other peoples rate of replenishment on them.
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Also, at what temp do you have the distillation vessel @?
Every white tank gets a fresh batch of x13 and alumacel. Its a 6x48 column that we fill.
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The heater fluctuates from 110-120f.
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are you running standard 100lb dot tanks or 500lb pig tanks?
Standard 100lb tanks. Since this issue came up in 2021 we have just been extremely aggressive on ways to mitigate it.
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I haven’t seen a problem yet, but thank you for the heads up!
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I have just been alerted to this, and want you to know that we take these issues very seriously. I am looking over our current notes on the situation, and can assure you that we will be taking measures to help you find the source of your issue and get you back on track.
I can assure you we do know where our gas is coming from, but since we offer different gasses, we will need to reference the serial numbers from the tanks in question to determine which source they came from. I am always happy to do more research into the issue, and would love to get the serial numbers from you so I can really start digging into the issue further.
We are sending a gas test kit to you that you can use to check for the presence of benzene in the gas. This will help to confirm whether or not the gas contained benzene prior to extraction. While there may be other sources of benzene in your final product, we would like to ensure it is not coming from the gas before going down the rabbit hole of terpene degradation and recently new testing standards that could possibly be affecting the test results.
Can you post a bit more info on your issues? Is it all products made with the gas in question testing positive for benzene, or only certain consistencies? What type of post processing is being done on material testing positive for benzene? Have you been using the same testing lab since the issue began? I would love to discuss this with you further to get to the bottom of the situation.
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For what its worth, raw materials in a GMP environment should be delivered and sit in quarantine until they’re released by QC/QA for use in production. QC should be testing incoming raw materials with an established quality spec in mind, which the vendor should be aware of in advance, and rejecting anything that fails the QC spec. You could even go so far as to have an agreement with your solvent provider that if their 'benzene free butane" contains benzene, you get your money back or solvent replaced.
That is to say, you could be testing your incoming solvents and rejecting anything contaminated with benzene before you contaminate your production equipment and materials.
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Could you help the rest of us out and say where we can get a reliable test kit?
@eyeworm is 100% correct, our QC department should be testing all incoming gases prior to use.
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Well, you (and presumably everyone else) are not going to be stoked to learn its probably a GC. While a GC-MS is going to be perhaps the most expensive/exhaustive, you could probably do a pretty good job with GC-FID.
I’m nowhere near being a true analytical chemist, so don’t rely on me to help choose the best detector in terms of price/necessary accuracy. But certainly MS and FID should both work since hydrocarbons have mass and contain carbon and hydrogen. FID is the obviously cheaper/simpler of the two.
Alternatively, a local environmental analysis company should have a GC and ability to test solvents. Its worth putting some pressure on your gas suppliers to have COAs and internal QC for their products. It’s kinda crazy to me that someone could be a large scale chemical vendor and just be flying blind. There’s no law stating the gas vendors can’t buy a GC, learn how to run it, and issue their own COAs. Sigma Aldrich certainly issues their own COAs on reagents.
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Dang! I figured there might be some Drager tubes or something we could use. That would give you at least a qualitative shot
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I’m sure you could rig up a cheap Sri for this. eBay special.
I know high precision gas has inhouse gc-ms for testing lots in their yards. Should only take 5-15 mins to test a tank once you have the sop
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We have had Sensidyne colorimetric detector tubes recommended for qualitative detection of benzene. They supply tubes that are able to detect benzene in the range of 0.1-75ppm. These are used in conjunction with a gas detector pump that meters a 50ml or 100ml volume of gas. There are other tubes available for qualitative analysis of many other chemicals as well.
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Maybe I’m just reading this wrong but won’t 4a sieve remove benzene?
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If 4a will then the 10a he’s using with the alumicel will even pull more.
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Testing would help but my math shows a problematic amount of benzene could be as little as 1 part per 100 million. I’ve never seen a coa with that low of a detection level. That would be a pass on pretty much any test I’ve seen.
This is worst case scenario but could explain how it slips through the cracks sometimes.
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