[tomek]

I am intending ordering Pd/C from Sigma-Aldrich. They offer variety of that stuff (5%, 10%, wet or not). I would like to ask whether you have experience with that catalyst, especially if you recommend the moistened with water one http://www.sigmaaldrich.com/catalog/product/aldrich/75993 or the other one http://www.sigmaaldrich.com/catalog/product/aldrich/75990. Any other tips would be grately appreciated. Thx.

[TheUnassuming]

I default to dry/activated 10% Pd/C.   Pd/C is relatively stable, so buying from aldrich is probably ok.  With more sensitive catalysts you should check out strem since in our lab at least, the quality of catalyst from aldrich is less reliable.

Just make sure the catalyst is under inert atm before you add your solvent to avoid sparking/fires.

[pgk]

It is obvious that Pd/C  at 10% w/w is more active and so, you put lower amounts in the reaction medium. On the other hand, handling of wet Pd/C  at 5% w/w is less is more safe but you cannot use wet Pd/C for substances that are sensible to hydrolysis. All depends on the type of compounds and the type of reactions that you are working with.
Important: During hydrogenations with Pd/C , always leave a window slightly open and keep a good aeration. Hydrogen may form metastable explosive gas with the atmospheric oxygen.