In the past, Google has said not to use pipes in URLs because it is one of the characters than can imply other things. But using them in your title tags is fine and I see it often.

Google’s Gary Illyes said on Twitter “doesn’t matter” if you use pipes or not in your title tags. Here is the exchange of tweets:

Truth is, I bet having them in your URLs don’t matter these days as well.

But from 2010, John Mueller of Google wrote:

Forum discussion at Twitter.