FumeHood

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Project FumeHood
Hood1.jpg
Status In progress
Contact Mux, PeterC, Peterbjornx
Last Update 2018-11-26


For some time now, there has been some interest in performing chemistry experiments and the like at RevSpace, with PeterC having amassed a decent amount of glassware and chemicals over the past 2 years. Until recently, we did not have a safe and contained area to actually perform any experiments in. Project FumeHood has changed that, and now provides:

  • A safe fume cupboard, made from chemically inert materials, to do the experiments in
  • Providing within the fume cupboard all the amenities you expect in a proper chemistry lab: electric outlets, gas connections, water connections, vacuum takeoff and of course air extraction
  • Dedicated, safe storage for glassware and chemicals
  • A wide assortment of compatible glassware
  • A few necessary chemicals (you will usually have to supply your own specialty chemicals or replace whatever you used, except for proportionally tiny amounts or bulk chemicals)

The goings-on with the fume hood, at least initially, will mostly be documented on mux's Youtube channel PowerElectronicsBlog. There are various videos, from a public overview of the fumehood to special instructional videos on how to use the fume hood. Watch them all here, and DONT FUCKING FORGET TO LEAVE A LIKE, COMMENT, SUBSCRIBE AND GIVE ME MONEY ON PATREON:

Current Affairs

Google Doc with synthesis plans

This section lists the currently planned experiments as well as other relevant goings-on in the fume hood. This section is periodically updated and cleaned up by the current head honcho: mux

  • Fumehood can currently NOT be used, preparations for metallic potassium synthesis are currently in the fumehood.
  • Mon 26 Nov: metallic potassium synthesis (PeterC and mux)

Ground Rules

The ground rules for the fumehood are:

  • The fumehood must be empty when it’s not in use for an experiment
  • Experiments can only be performed with prior approval
  • Chemicals need to be correctly and safely stored in the appropriate level of the closet or drawers
  • The fumehood can never be used by just one person
  • Any experiment has to be attended to at all times, so no overnight experiments (unless you have 2 people stay overnight)
  • Fellow spacers should be informed appropriately when an experiment is ongoing
  • You are responsible for the chemical waste you generate

Any broken rule should be immediately noted and if possible righted. If somebody absent-minded stored some widget inside the fume hood, take it out and put it in the person’s samla. If somebody seems to be working by themselves on an experiment, ask if you can be their buddy or inform the kaiser of this. Maybe their chem buddy got sick and they’re still cleaning up but they forgot to tell anyone.

Responsible person

Everything that happens with the fumehood of any significance should be reported to one responsible person: mux. By request you can get his e-mail, phone number, Signal, Hangouts, whatever you like. Just ask on IRC or in person, or any other way you see fit.

Experiment planning and approval

If you intend to do an experiment in the fumehood, you have to make a plan, submit it to the head honcho and get it approved and planned. You will need to:

  • State which reagents you will use and what synthesis you wish to perform (if possible: links to papers/procedures/whatever you’re using)
  • Describe the apparatus(es) you will use
  • Explain the risks of every step in your synthesis and have contingency plans for when anything goes wrong
  • Estimate how long you will want to use the fumehood
  • Explain in detail how you will clean everything and how long this will take
  • Say when you wish to do your experiment
  • Name a person or persons(s) you will be doing the experiment with

Depending on your experiment, you may either just go ahead, or you may have to schedule a time where either a trained chemist or experienced person is available as well to observe the experiment.

The focus of any application is on safety and clean-up. You will always be asked to reserve lots of time for prep and cleanup, so keep that in mind.

The fumehood may be used to ventilate smelly things or accidents in the space safely without planning.

Glassware and Hardware

All glassware is standardized to 29/32 ground glass fittings, for which we have appropriate clips. There is currently no up-to-date list of glassware, this is being worked on.

The fume hood has been designed to work with floating lattice work. In order to build an apparatus, take out a nylon screw in a location where you want to put a bar and screw in one of the threaded M10 rods. You can now use either finger clamps or screw clamps (in the top 2 drawers) to attach glassware to your lattice. There should be plenty of room in the fume hood to build any apparatus you need, up to even fractional distillation setups, all floating above the work surface.

There is a hot plate stirrer in the top-right drawer. This cannot be suspended, so place your boiling flask close to the work surface. Elevating the hot plate stirrer is not recommended, whatever you use for this is likely not going to be very chemically resistant or sturdy and you will just damage the HPS. Also keep the HPS away from corrosive atmospheres, as it is not a sealed unit!

Wash and dry glassware, then return it to the correct positions in the drawers. Any broken or missing glassware should be reported, we don't bite!

Use vaseline on ground glass joints to prevent them sticking together. In experiments that use sulfuric acid, use concentrated sulfuric acid instead. Carefully clean the joints afterwards if you lubricate them with sulfuric acid!

We have a vacuum pump; it is a carbon vane type that cannot produce a particularly strong vacuum. It has been attacked by an HCl/HNO3 atmosphere and rebuilt, but has suffered significantly. It can be used for vacuum filtrations, but not much more. Use a bubbler when vacuuming off noxious atmospheres!

Chemical storage, allowed and prohibited chemicals

The inventory if glassware and hardware is currently being compiled and supplemented. Work in progress.

Chemical reagents (except for distilled water, isopropanol, waste, and temporarily stored project chemicals) are listed on the inside of the yellow locker cabinet doors to the right of the fume hood. Each bottle is labeled with a number (1-5) corresponding to the appropriate level of the cabinet it should reside in. A digital inventory of the fume hood is also kept on Quartzy: Quartzy: Department of Chemistry. (you need to log in to access this so ask Mux or PeterC to email you an invite).

All liquids need secondary containment, this is provided by the glass trays found in cabinets 1,3,4, and 5.

The bulk of the solids in chemical cabinet 2 are in small samlas, this means that you must carefully take out the samla to access the chemical inside.

If you need chemicals that we don’t have for a project and don’t know where to source them you can ask mux or PeterC.

If anything breaks, is added, runs out, and mux is not available to manage this, just put it under the Current Affairs section of this page.

Prohibited chemicals

Significantly radioactive materials are absolutely forbidden. Yes, we have asked and the answer is a very empathetic no. And if anybody even tries, there are very hefty fines and prison sentences attached. This even goes for depleted ores.

Any chemicals that are known to attack glass are strictly prohibited. This includes but is not limited to:

  • Molten sodium hydroxide
  • Hydrogen fluoride (yes, also very dilute solutions!)

Additionally, the following chemicals can only be used if absolutely no other options are available and if the responsible person is convince you can handle them responsibly:

  • Fuming nitric acid
  • Thermite (which includes ANY exothermic metal-metal oxide reaction, not just aluminum and iron oxide)

Fume hood construction details

Constructing a fume hood on a tight budget isn’t that easy as we found out. The construction of this fume hood was plagued with things that didn’t quite go right and had to be fixed - so let this story be both a cautionary tale and a guide to doing things better than we did!

The main function of a fume hood is to be a relatively chemically inert space that contains any hazardous chemicals used or created in chemistry experiments. Things will go wrong, and if they do, the fume hood is there to protect both the operator and the rest of the hackerspace.

The fume hood provides an approx. 50cm deep, 100cm wide, 95cm tall workspace, with 4 drawers and a lockable (though not particuarly secure) compartment. The fume hood has a single, balanced, vertically travelling window.

Containment and disposal of hazardous substances

The fume hood has been constructed to deal with the inevitable spills, smoke production and the like by way of:

  • The extraction fan; rated at approx. 100m3/h, it has the capacity to remove the entire volume of the fume hood every 30 seconds or so. For maximum airflow, make sure the window is NOT completely closed.
  • The glass fiber liner. The entire inside of the fume hood is lined in glass fiber reinforced polyester, which is chemically inert to pretty much everything (see prohibited chemicals below). The hardware mounting holes are closed off with nylon screws.
  • The lip; any spill (or coolant leakage) up to approx. 20L will be contained by the 4.5-cm lip.
  • The glass work surface. Any small spills will run off the raised work surface, keeping the workspace clear to put bottles or other materials on if something goes wrong
  • The polycarbonate window. The window is shatter-proof and mounted flexibly, so any explosions should be contained and - worst case - cause the entire window to be blown out instead of lots of small shards.
  • The double walls. The fume hood is a double-walled construction - which aside from being convenient for cable routing, also provides effective containment of flying debris and exploding glassware

Other safety features

  • The electrical system has its own emergency shutdown button and a selective GFCI. (this also means you are NOT allowed to run electricity into the fume hood from anything but the built-in outlets!)
  • The fan, light and water can be turned on/off from the operator position in front of the fume hood
  • Through-wall, sealed brass water and gas inlets/outlets so you should NEVER need to run hoses through the window
  • Suspended latticework to put an apparatus on; any spills will automatically drop down onto the work surface out of the way of other reagents.

So, what’s the problem?

So far, it seems like the fume hood is pretty sweet! Well, the construction was plagued with more than a few issues:

  • The wooden frame, after assembly, parallellogrammed to make the entire fume hood crooked. This had to be corrected by screwing on a solid steel sheet frame to the front of the fume hood.
  • The glass fiber liner did not finish very evenly, even with a layer of (pigmented) gelcoat. Ideally, the fume hood should be a very even glossy white on the inside, but this finish could not be attained. The patchy appearance of the gelcoated glass fiber was fixed by painting the inside, but the paint is of course a lot more reactive than the glass fiber, so in particular acid spills will leave visible marks instead of wiping off easily. This is not a safety hazard, just an aesthetic problem.
  • The drawer rails, despite being rated up to 60kg, had trouble dealing even with the weight of the drawers themselves when fully extended and did not operate smoothly. This was fixed with telescoping rails.
  • The first window did not operate smoothly. Neither did the hotfix for that window. This was fixed by rebuilding the window on telescoping rails and adding counterweights.
  • Including glassware purchases, the budget was overshot by approx. €400
  • A filter box was designed (and still hangs on the wall), to be filled with variously activated charcoal filters. Unfortunately, this proved to be quite ineffective as a general purpose filter. The initially planned military-grade filter cans went out of stock the week we tried to purchase some. In the end, we figured maximizing airflow is a better approach than trying to chemically trap any problematic atmospheres.

These points by themselves aren’t the end of the world - they were mostly consequences of trying to construct a cheap fume hood - which was still successful. The biggest issue was a lack of time. Construction was supposed to be a team effort, but a confluence of factors (most notably: trying to plan anything big in a hackerspace) meant that time for construction was limited and the project proved too big for the main constructor. This let the project timeline drag on for about 9 months longer than it was supposed to, almost axing the project entirely.

Project ideas

The fume hood will of course be used for science experiments! Among these may be:

  • Making a lithium-ion battery (also involves project Smeltoven, using the original li-ion battery paper as a guide)
  • Gold, palladium and platinum recovery from computer components using the cyanide pathway (also involves project Smeltoven, we have materials to make cupels and might use Cody's Lab's cyanide from cherry pits-method)
  • Chip decapping
  • Making sodium and/or potassium metal using the new tea tree oil (3-Terpineol) catalyzed Nurdrage method
  • Playing with project DIY solid-state stirrer
  • Anodizing aluminum (and doing it right this time!)
  • Making sodium silicide (for hydrogen production)
  • Demonstration project: glowsticks (TCPO method)
  • Demonstration project: copper salt crystal growth
  • Demonstration project: basic electrolysis
  • Demonstration project: Clock reaction
  • Making aerogels
  • Synthesizing organic and inorganic dyes

ToDo list

There is always more work to do.

  • Make an inventory of all glassware and label glassware appropriately
  • Improve bottom drawer's layout so items can be found more easily (the bottom drawer is primarily for bulk storage of consumables)
  • Add a level and a ceiling to the lockable cabinet area
  • Re-paint the entire inside of the fume hood so it's all an even color (lip and exhaust are currently significantly discolored)
  • Replace pulleys with types that have a cage around the wire (to catch a wire if it falls off)
  • Add a faceplate to the top of the fume hood so the pulley mounting and wiring isn't visible and, more importantly, so people aren't as likely to put stuff on top of the fume hood.