差热分析法测定多元醇的比热

Heat Capacity of Glycol Determined by Differential Scanning Calorimeter

利用差示扫描量热计测定了乙二醇、丙二醇、丁二醇和叔丁醇在不同温度范围内的比热.为了验证仪器的准确性,实验测定二次蒸馏水在20～80℃的比热,并与文献值进行了对比.测定水时仪器测量误差在2%以内,并且把测得的各种醇的比热与文献值进行了对比,比热测量值的精度完全能满足工程计算的要求.同时回归出了它们的Cp随温度的变化关系,可供工程计算中参考.

Measurements of the heat capacities of the ethylene glycol, 1,2propanediol , 1,4butanediol and tertbutanol were performed at different temperature range with a differential scanning calorimeter(DSC). The heat capacity of liquid water from 20℃～80℃ has been measured to verify the validity of the Cp measurements. The measured values are compared with the literature data. The error is less than 2%. The measured Cp of each glycol has been expressed as a function of temperature. The measured heat capacities are of sufficient accuracy for most engineeringdesign calculation.