The recycling industry has a dirty little secret: Much of the plastic that consumers diligently sort is never actually recycled. Instead, some of those yogurt containers, translucent takeout boxes and bottle caps are buried in landfills or incinerated. The issue isn’t a lack of demand for this recycled plastic — specifically items with codes No. 3 through No. 7. Big companies like Johnson & Johnson and Procter & Gamble, hoping to burnish their environmental credentials,…