2007 Volume 40 Issue 13 Pages 1281-1286
The mixing effect of transition metal ion into magnesium hydroxide on dehydration and hydration reactivity was studied to develop a new material for chemical heat-storage, because the mixing effect was expected to reduce dehydration-temperature, corresponding to heat-storage temperature, of authentic magnesium hydroxide. Two-components composite materials mixed with some content of nickel ion or cobalt ion into magnesium hydroxide were tested, respectively. It was demonstrated that the dehydration-temperatures of the composites were shifted to lower temperature below 300°C with increase of nickel or cobalt content in comparison with dehydration-temperature of authentic magnesium oxide of 350°C. These composites showed higher hydration reactivity than that for authentic magnesium oxide under the same reaction condition, and were expected to be applicable to heat utilization of middle-temperature waste heat less than 300°C.