摘要
当体系温度<60℃时,在一定的温度、CO_2分压下,估算值与实测相近,如60℃,CO_2分压分别为7.0 MPa和8.0 MPa时,估算值与实测的相对误差分别为2.8%和1.8%。pH值随温度、CO_2分压的变化规律,也和实测的变化规律相同。因为未见报道温度>60℃时,一定压力下碳酸溶液的pH值,本文选择了合适的数学模型,通过合理简化,用MATLAB估算出CO_2-H_2O体系中碳酸溶液的pH值。因此,在一定的CO_2分压下,高温时pH的估算值及其变化规律可信,能够用估算碳酸溶液的pH值解释在CO_2-H_2O体系中,原位形成碳酸溶液的酸性对化学反应的影响,也可以预测在上述体系中的酸催化化学反应时,体系的酸性是否能满足要求。
The calculated pH values are close to the experimental data when the temperature is less than 60℃ under a given pressure. For example, when the temperature is 60＂C under 7.0 MPa and 8.0 MPa, the pH value relative errors are 2.8% and 1.8%, respectively. Because there are not pH values reported in the literature, when the temperature is greater than 60℃ under a given pressure, in this paper, the pH values in CO2-H20 system has been estimated using MATLAB through the reasonable simplification by the mathematical model. Furthermore, the changes of pH value with the change of the temperature or pressure are similar to that in the reference. So, under a given pressure when the temperature is higher than 60℃, the value and its changes estimated are right not only to interpret the phenomena of the chemical reactions in CO2 - H2O system, but also to predict whether other acid-catalyzed reactions take place in above system.
出处
《计算机与应用化学》
CAS
CSCD
北大核心
2011年第3期359-362,共4页
Computers and Applied Chemistry
