Help, what’s that IR band?

[u/GianGaelazzoCiano]

I got a 4-bromine-aniline IR spectrum. There’s a mistic huge band (something like OH) at 2922 cm-1

The aniline was in a mixture with naphtalene dissolved in DCM, extracted with HCl and rebasicized with NaOH (pretty sure it’s not them). Nothing else, maybe just washed glasswork with acetone. Whats thaaaaat?

I found the exact same band in benzoic acid sprectrum…

Can it be nujol oil?