[Honclbrif]

Hey Guys,

I've been trying to reduce a nitro group. SnCl₂ and Fe have only provided sadly low yields so I'm considering hydrogenation with Pd(C) and H₂. The conditions are pretty simple, I'm not worried about them (MeOH, 50°, H₂ balloon). However, no one in my lab has used this reagent before, so my question is: how do I dispose of the spent catalyst without burning down the lab? I'll be using small quantities, only about 100 mg.

Thanks

[discodermolide]

Hey Guys,

I've been trying to reduce a nitro group. SnCl₂ and Fe have only provided sadly low yields so I'm considering hydrogenation with Pd(C) and H₂. The conditions are pretty simple, I'm not worried about them (MeOH, 50°, H₂ balloon). However, no one in my lab has used this reagent before, so my question is: how do I dispose of the spent catalyst without burning down the lab? I'll be using small quantities, only about 100 mg.

Thanks

Put the catalyst residue  plus filter, filter aid in a properly labelled bottle and cover the solids with water. When it is full you can return it to the manufacturer for re-cycling.

[asa029]

I just filter it off and place both the filter paper and the spent catalyst in an empty container. I've never filled it with water, but maybe that would be safer:D

[discodermolide]

I just filter it off and place both the filter paper and the spent catalyst in an empty container. I've never filled it with water, but maybe that would be safer:D

Water stops it from drying out and catching fire!

[Dan]

Make sure you degas the mixture before exposing it to air. Evacuate and charge with nitrogen or argon at least 3 times before you take the lid off. If there is still hydrogen on the Pd, it can catch fire during filtration. This is why I normally like to do these reaction in water and not a flammable solvent if possible.

Several years ago I set my glove on fire working with Pd black and not degassing properly. Luckily no injuries. 10% Pd/C is not as feisty, but don't take risks with it, I certainly do not any more.

If you degas properly, the Pd/C residues should be harmless - but always store them wet, as discodermolide has detailed already.

[Honclbrif]

Thoroughly degas and never allow the material to dry out. I shall do these things.

Thanks Guys