I kitbashed this HEPA + carbon air filter out of a couple of different source files in 2018, none of which I can remember the provenance of. Let me know if parts of this look like your work and I'll be sure to add an attribution.
This uses a 24V blower from a MakerBot Rep2, however any common 50x50x15mm blower with the same bolt pattern will mount up just fine.
The Body, Lid and Blower Adapter glue together. There is one Baffle in each side, and they should slide freely after installation. Push them towards the top to redirect air coming in through the filters into the carbon column. The blower mounts to the Adapter with long M2 bolts that tap directly into the Adapter plastic.
The HEPA filters are from the Roomba 800 and 900 series robotic vacuums and can be purchased online for $1 to $1.50 each. This design uses two of them.
The activated charcoal that I use is "4x8 Activated Carbon - Virgin Coconut Shell Charcoal". This material is manufactured specifically for vapor filtration and removing VOCs. It's about $4.50 USD/pound and lasts an exceptionally long time. I run seven printers with these filters and I'm still on my first 20 lb bag four years later.
This setup is great at mitigating both stinky FDM filaments (ABS, nylon, etc) and SLA resin printers as well.