Solvay’s chemicals segment, the world’s leading producer of soda ash, reported a 55% increase in profits for the first quarter of 2011 on higher volumes and sales prices, the Belgian company said.The segment pulled in recurring earnings before interest and tax (REBIT) of €101m. ($150m.) compared with €65m. in the same period last year, while sales rose 23% to €800m.“The sustained level of demand contributed...