Sciencemadness Discussion Board

tiles and grout in a fume cupboard

NEMO-Chemistry - 10-7-2017 at 11:37

To cut costs and make life a little easier, i was going to tile the walls of the inside of my fumecupboard.

the sides are wooden so i figured covering with ceramic tiles would be a better option. Not knowing what grout and tile adhesive is made from however, my question... is there any particular tile adhesive or grout i should use so it dosnt react with spills?

or maybe put a bead of silicon around the tile edges where the tiles meet?

The other question is exhaust height, is there a ideal height for the flu of the exhaust so fumes dont linger around the outside of the building?

MrHomeScientist - 10-7-2017 at 12:07

I'd bet money on grout being some kind of carbonate, which would react with acids.

When tiling my lab, I used a grout sealant to help mitigate that. It's a clear coating you just paint onto the grout lines, making them water-repellant. Silicone would be a good option for a fume hood. Silicon, on the other hand, may be difficult as it melts at 1414C!

phlogiston - 10-7-2017 at 12:45

Old fumehoods sometimes have tiles, but I can't find any information on the grout that was used for them. Commonly available grouts are usually cement-based and not very acid resistant. Sealing, e.g. with silicone, seems like a good strategy. I am not fond of ceramic/tiled fumehoods because they are very unforgiving if you drop a piece of glassware even from a small height.

Regarding height of the exhaust, it depends on you building and other buildings in the vicinity. I think looking at the regulations for fireplace-chimneys may help to at least get some idea of the principle.

[Edited on 10-7-2017 by phlogiston]

JJay - 10-7-2017 at 15:25

I am planning on coating the inside of my fume hood with plaster of Paris. It's mainly calcium sulfate, which is pretty inert at normal temperatures. It can be used as a grout, although it's harder to apply than most commercial grouts.

If you decide to go that route, be aware that it can produce burns as it sets: http://www.mirror.co.uk/news/uk-news/art-class-girl-loses-ei...

NEMO-Chemistry - 10-7-2017 at 16:07

Thanks for the info. calcium sulphate sounds like a great idea. The chances are the tiles will mostly be the back and sides. getting the tape measure out i realized i could actually use the sink draining board for the bottom. its not plastic exactly and i am not 100% sure what it is made of, but its some Dupont material thats a bit like plastic except not flammable etc and very heat r3esistant. It also seems totally inert to everything i have thrown at it :D.

the downside is its a mare to cut, blunts a circular saw blade pretty quick. And being a kitchen unit has a horrid pinky colour with black flecks in!!
the silicon i was thinking of is the fishtank bathroom type sealer, but i do like the calcium sulphate option :D.

Magpie - 11-7-2017 at 07:59

Quote: Originally posted by JJay  
I am planning on coating the inside of my fume hood with plaster of Paris. It's mainly calcium sulfate, which is pretty inert at normal temperatures....


Sheetrock (wall board) is mostly hydrated calcium sulfate, ie, Plaster-of-Paris.

JJay - 11-7-2017 at 09:03

I considered making the entire thing out of sheetrock, but I want it to be semi-portable, and I'm not sure if sheetrock is strong enough. I've seen fiber-reinforced sheetrock panels, but they are expensive.

NEMO-Chemistry - 13-7-2017 at 17:57

Just an update, the tile cement wasnt that good on wood, so i ended up using 'no nails glue. stuck the buggers or really good and then I used silicon sealer instead of grout.

Not finished yet, so next question.... is it ok to use the orange type soil pipe for the exhaust? I think its a type of PVC but not 100% sure.

Magpie - 13-7-2017 at 19:46

I use 8" PVC for the exhaust duct - works great.

NedsHead - 14-7-2017 at 00:43

If you're worried about breaking glassware on ceramic tiles you could line the base of the fume cupboard with silicone baking sheet, silicone cookware and utensils have become popular and some of them are quite useful for purposes other than baking, e.g. spreading flux with a silicone brush when soldering / brazing

NEMO-Chemistry - 14-7-2017 at 04:20

Thanks magpie, i couldnt remember which colour of pipe was a no no, the orange stuff is cheap and easy to work with.

nead the base is a kitchen worktop, no idea the material but its chemical resistant and not as destructive as tiles for dropping things on :D. the sink is made from the same stuff.

Now the sad bit..........
Got to rip it all down again! I havnt made it tall enough to get a lab jack mantle and 400mm condenser in!! Also I was really unhappy with having exposed copper pipes inside it.

On the plus side ebay has thrown up a huge amount of kitchen cupboards and units including inbuilt fridge all for £25!!! Ok kitchen units might be naff to a purest but storage is one problem i have

veganalchemist - 14-7-2017 at 07:32

Can you not just line the fumehood with sheets of glass?

Sulaiman - 14-7-2017 at 07:58

Quote: Originally posted by NEMO-Chemistry  

Now the sad bit..........
Got to rip it all down again! I havnt made it tall enough to get a lab jack mantle and 400mm condenser in!!


You may want to consider allowing for the additional height of a vertical column for fractional distillation too.

JJay - 14-7-2017 at 11:42

You also need space for the thermometer above the column. I'm designing mine so the work area is about 110 cm high, and I'm actually not sure I'll be able to fit a 60 cm fractionating column.

NEMO-Chemistry - 14-7-2017 at 12:01

Quote: Originally posted by JJay  
You also need space for the thermometer above the column. I'm designing mine so the work area is about 110 cm high, and I'm actually not sure I'll be able to fit a 60 cm fractionating column.


Sorry i was on about a fractional column, The upside is there are a few changes I can make now, making it from wood and double glazed glass means its not too big a deal to redo.

Except more tiling which I hate :D.