Yes the ultra-dry super hydrophobic coating and you can use it in concrete mixers. It can be applied on metal surfaces. Provided you completely clean the mixer to metal. And then apply two part coating. Bottom and top coat. You can buy it from Online retailers in US , like even amazon. The coated surface will become white. The application within the concrete mixer is little tricky as over time the aggregate will damage the coating so it will not last long comparing any other surface. It will work though effectively. price is around $200 for top and bottom coat : one liter each.
Coverage is 6 square meters per liter for each top and bottom products. So with 200 dollars you cover 6 square meters. Also as you have to buy from US, add another 200 or even more easily for shipping. You have to check with buyer if they ship overseas. As even here it is sold to commercial consumers only.
Now depends how much your mixer cost. Let me know if you need more info. I have a sample in my lab
On the side note; Its not a product for automotive paint. the base coat has xylene and you know what it will do to your paint.