From: "CHANDRA, Tilak" <tchandra**At_Symbol_Here**FPM.WISC.EDU>
Subject: Re: [DCHAS-L] Quick question for the group
Date: Thu, 25 Jun 2015 16:09:45 +0000
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: F0915977-6ED3-4CDE-B405-E483B746C13A**At_Symbol_Here**

I completely agree with Brandon, and researchers will be hesitant to use recycled solvent to purify the product. This can be only achieved at researchers side, and use of single solvent for chromatography may reduce the qty. of the solvent upon recycling.
When solvent is removed from column fractions using rotary, will also take water (moisture) and grease from the joints.


Sent from my iPhone

On Jun 25, 2015, at 10:34 AM, Brandon S. Chance <bchance**At_Symbol_Here**PRINCETON.EDU> wrote:


I am going to play devil's advocate here and would love to hear some of the other responses to this, but have you broached these thoughts with your researchers?  The waste stream you mentioned is primarily from column chromatography, where large volumes of solvent are used to purify and isolate compounds.  These same combinations ae used in thin layer chromatography to identify compounds as they come off of the column.  I have broached the topic of distilling and reusing ethyl acetate and hexanes at two different research institutions.  In both cases the researchers were steadfast that they would not use reclaimed EtOAc or hexanes in their research due to purity concerns.

If you chose to pursue this, it would have to have buy in from the researchers and you most likely would have to have analytical testing demonstrating its purity before a researcher would ever consider using it. 

On the other hand, if your undergraduate labs are also large consumers, you could potentially take the large volumes collected from the researchers and reuse as much as you can in the undergraduate labs where they are learning the techniques for TLC and column chromatography, but not as concerned about product purity.  

For the rest of the listserv:  Have any other research institutions had any luck in getting their researchers to buy into reusing solvents processed in house?


Brandon S. Chance, M.S., CCHO

Program Manager, Chemical Safety

Environmental Health and Safety

Princeton University

262 Alexander Street

Princeton, NJ 08540

609-258-7882 (office)

609-955-1289 (mobile)

609-258-1804 (fax)

"… our job in safety is to make the task happen, SAFELY; not to interfere with the work…" Neal Langerman

From: Jake Hernandez <Jake.Hernandez**At_Symbol_Here**UTSA.EDU>
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Date: Thursday, June 25, 2015 at 9:22 AM
Subject: Re: [DCHAS-L] Quick question for the group


That is a good point. We are new to this status and we are slowly figuring out the complexities. I think we need to get a permit just to be on the safe side. Thank you for your response.


Best regards,

Jake Hernandez

Safety Specilaist 2

Lab Safety Division

(210)458-5807 voice

(210)336-9509 cell






From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**] On Behalf Of Dr. Carlos Rentas Jr., DPH CSP
Sent: Wednesday, June 24, 2015 8:22 PM
Subject: Re: [DCHAS-L] Quick question for the group


Jake, unless you can manage to incorporate the separation procedure into a lab exercise this may be construed as treatment of waste requiring least that was the position of the NYS Department of Environmental Conservation and I believe the EPA, but you may want to check with other experts in this area (I've been away from this activity for a few years). Hope it's helpful. 

Carlos Rentas Jr., DPH CSP CHMM

Certified Safety, Health & Environmental Consultant

Innovative Solutions in EH&S, LLC

Flushing, New York 11358

B (888) 315-2498 C (718) 216-6057

On Jun 24, 2015, at 5:53 PM, Jake Hernandez <Jake.Hernandez**At_Symbol_Here**UTSA.EDU> wrote:


Our university just recently became a large quantity waste generator. We have been trying to find ways to reduce/reuse/recycle. One of our largest wastes is from the organic chemists. The waste in question is hexane/ethyl acetate. Has anyone heard of a way to separate these two and reuse them?


Thank you,


Jake Hernandez

Safety Specilaist 2

Lab Safety Division

(210)458-5807 voice

(210)336-9509 cell




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