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Hi Jeff, We had exactly the same problems with external samples we had not prepared ourselves. Problem samples included certain type of soil samples, samples that had been HCl acidified, and marine samples. In addition to quartz inserts fusing with the reactor, the reactors developed pin-prick holes through which molten tin tears escaped. Essentially what happens is that contaminants such as alkali and earth alkaline cations will ‘migrate’ into the quartz glass (pure SiOx) forming weaker metal-O bonds which in turn lowers softening point and melting point of the now no longer pure quartz glass. With the help of Stuart Carter at OEA Labs we developed an insert made of Inconel which “solved” this problem by circumventing it. We presented this as a poster at the 2013 EGU in Vienna. Contact Stuart at [log in to unmask]<mailto:[log in to unmask]>. I am sure he will be able to help. Best, Wolfram From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Jeff Havig Sent: 19 February 2017 19:07 To: [log in to unmask] Subject: [ISOGEOCHEM] EA insert fusing to oxidation column Hello Analytical Experts- I am running a Costech Elemental Analyzer attached to a Delta V Advantage IR-MS, and have been having issues with the combustion chamber quartz insert fusing to the oxidation column (we have had to the replace the oxidation column three times now because of this, and this is less than ideal). Our setup: The insert has ~ 1 cm of quartz wool at the bottom with ~2-3 mm of Chromium(III) oxide on top of that. I have been using the medium (5x9 mm) tin capsules for loading samples (49 per run, 2 to 3 runs per insert). The samples I have been running include volcanically-derived glacial sediments, snow algae, and hot spring biofilms (mostly composed of amorphous silica). Some of the samples have been acidified with HCl to remove DIC and carbonates, but have all been rinsed with 18.2 MOhm/cm water to remove all Cl- before drying and grinding. It seems as though the insert quartz is fluxing and being stripped away, enlarging the slit openings and weakening the insert, allowing the tin to leave the side slits and fuse the insert to the inside wall of the oxidation column. Also, there seems to be a tendency for yellow-ish melt/precipitate to form at the bottom of the insert, fusing it to the oxidation column there as well. I have attached an image (pdf) of the last failure with examples of what I am trying to describe. The temperature of the combustion chamber/oxidation chamber is at 1000 C (checked with thermocouple). This has happened a few times in the past, but never consistently like this. If any of you happen to have had this problem and might know 1) what is going on, and 2) the best way to fix the problem, I would be eternally grateful for your time and help. -Jeff -- Jeff Havig, Ph.D. Adjunct Faculty Room 517 Geology-Physics Building Department of Geology McMicken College of Arts and Sciences University of Cincinnati Cincinnati, OH 45221-0013 MAD EGG LAB Website<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.jeffhavig.com&d=DQMFaQ&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=mlRDJltM2svd6oAfq2MrwoAbV6hyAe0dizt9C3HcIFY&m=8jBKojpWI-hZQhUiAiiagVV8QeKo7DLm77rqPS2mkes&s=qY4lUjscCCgEQCZJSgWDBO-LGiPn7ptJN8r3hS8M41s&e=> https://scholar.google.com/citations?hl=en&user=wMfFwp8AAAAJ<https://urldefense.proofpoint.com/v2/url?u=https-3A__scholar.google.com_citations-3Fhl-3Den-26user-3DwMfFwp8AAAAJ&d=DQMFaQ&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=mlRDJltM2svd6oAfq2MrwoAbV6hyAe0dizt9C3HcIFY&m=8jBKojpWI-hZQhUiAiiagVV8QeKo7DLm77rqPS2mkes&s=Imaxs-Gsjl-eAvWt9swsqdSUvRba7tBSD8eW2Iyxxhw&e=> "There comes a time in every mans life where he has to look the potato of injustice right in the eye!" - Stanley Spadowsky, UHF "Always with the negative waves Moriarty, always with the negative waves." -Oddball, Kelly's Heroes ________________________________ This email has been scanned for spam and viruses by Proofpoint Essentials. Click here<https://eu1.proofpointessentials.com/index01.php?mod_id=11&mod_option=logitem&mail_id=1487531368-kueKNHX2FOnl&r_address=w.meier-augenstein%40rgu.ac.uk&report=1> to report this email as spam. ________________________________ Robert Gordon University is the top university for graduate jobs in the UK HESA July 2015 Robert Gordon University, a Scottish charity registered under charity number SC 013781. This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Please note that any views or opinions presented in this email are solely those of the author and do not necessarily represent those of Robert Gordon University. Thank you.