双季戊四醇在3种混合溶剂中的固-液相平衡

采用动态平衡法，在293.15～332.80 K、常压下，测定了双季戊四醇(DPE)在水+(甲醇、乙醇、异丙醇)三种混合溶剂中的溶解度数据。结果表明：DPE在不同质量分数的水+(甲醇、乙醇、异丙醇)混合溶剂中的溶解度随体系温度升高而增大；同一温度下，其在所选取溶剂体系中的溶解度随着甲醇、乙醇或异丙醇质量分数的增大而先增大后减小。λh方程、两参数方程与Apelblat方程均能够对所测定的溶解度数据进行较好的关联；通过修正的van’t Hoff方程计算得到DPE在所选取溶剂体系中Δ_sol H ⁰、Δ_sol S ⁰和Δ_sol G ⁰均大于零，表明DPE在所选取溶剂体系中的溶解过程为吸热、熵增的非自发过程。

Solid-liquid phase equilibrium of dipentaerythritol in three mixed solvents

In this paper, by the dynamic balance method, the solubility of dipentaerythritol (DPE) in water+(Methanol, ethanol, isopropanol) mixed solvents were evaluated from 293.15 K to 332.80 K under atmospheric pressure. The results showed that the solubility of DPE in different mass fractions of water + (methanol, ethanol, isopropanol) mixed solvents increases with the increasing of temperature. At the same temperature, the solubility in the selected solvent system increases first and then decreases with the increase of the mass fraction of methanol, ethanol or isopropanol. Experimental solubility data were correlated by three thermodynamic models including λh equation, the two parameters equation and the modified Apelblat equation. All the selected models give useful result in regression analysis of solubility. By the modified van t Hoff equation, the calculated Δ_sol H ⁰, Δ_sol S ⁰ and Δ_sol G ⁰ of DPE in the selected solvent system are all positive, indicating that the dissolution process is endothermic, entropic and non spontaneous.