The experiments of leaching ilmenite were conducted by using HCl-chloride salt solution and hydrochloride acid solution respectively. The results showed that when the concentration of hydrochloride acid was 18% with a liquid-solid ratio of 4. 2 at 135 ℃,the grade of synthetic rutile achieved by leaching with HCl-chloride salt solution for 30 min was similar to those achieved by leaching with hydrochloride acid solution for 1 h. After leaching for 1 h,the reaction by using HCl-chloride salt solution was near...