سال انتشار: ۱۳۸۲

محل انتشار: هشتمین کنگره ملی مهندسی شیمی ایران

تعداد صفحات: ۹

نویسنده(ها):

Mohammad Hadi Ghatee – Department of Chemistry, Shiraz University, Shiraz
Afsaneh Maleki – Department of Chemistry, Shiraz University, Shiraz

چکیده:

We explore the correlation between reduced surface tension and reduced temperature that have been developed and worked out recently. The general relation will be considered more fundamentally based on behavior of density profile of liquid- vapor coexisting curve. The correlation is characterized by the persistent linear behavior from freezing point up to the critical point. The slope of the correlation is a universal constant for those hydrocarbons for which surface tension data are available from freezing point to the critical temperature. We will discuss that since the slope is universal among hydrocarbon, quantitatively it must belong to a fundamental property of the system, which could demonstrate law of corresponding states. We have derived an analytical form from the slope and show that it is accurately constant ≈ ۱ from freezing point up to the critical point. We have applied the critical exponent μ =۱٫۲۶, however, the critical exponents that are derived from available experimental data are different. The application of derived μ , however, would not bring about appreciable differences in the result given by μ =۱٫۲۶٫ The relation for the
slope leads to a new form of relation surface energy, involving the critical exponent and the relation to the generic nature of surface entropy is pursued.