Even if water ice is not found on the Moon, the fact is that hydrogen and oxygen can be found on the Moon in other forms. How then could could these other materials containing hydrogen and oxygen be processed in bulk, in order to obtain water from them? What would be the most practical way? I'm thinking that the simplest approach would be thermal cracking, putting raw materials into a nuclear reactor to break them down and allow the hydrogen and oxygen to recombine into the water. What other methods would be good choices to achieve high throughput? It's funny - I don't think I've ever heard of much research going into synthesis of water, since it's such a naturally abundant substance on Earth.