One of the questions I had recently was about baby formula canisters, like the one pictured here.
Most of these containers are made out of liquid paperboard (LPB), a combination of paper and plastic (and sometimes also metal) to keep moisture out. In the City of Austin, these are not recyclable since they’re a composite/mixed material.
The canister goes in the trash. The sides are LPB, the bottom is metal, and would be difficult for a human or machine to break these apart.
The lid and the scoop are plastic and are recyclable.
The pop top (not pictured) is metal and recyclable.
You may compost any unused or expired formula.