2-(4-戊基苯甲酰)苯甲酸在C_6—C_8烷烃中溶解度的测定与关联

Measurement and correlation of solubility of 2-( 4-amylbenzoyl)benzoic acid in C_6-C_8 alkane

2-(4-戊基苯甲酰)苯甲酸(ABB酸)是合成2-戊基蒽醌的重要中间体,简便高效地从反应混合物中分离纯的ABB酸是合成2-戊基蒽醌的关键步骤。文中采用液相色谱仪内标法测试了ABB酸质量浓度范围为0.9×10-9—21×10-9g/L标准液的峰面积,建立了ABB酸质量浓度与峰面积的线性关系。利用该线性关系,采用平衡法实验测定了系列温度下,ABB酸在直链烷烃(正己烷、正庚烷、正辛烷)体积分数为0.750—0.875的直链烷烃/邻二氯苯混合液体系中的溶解度数据。ABB酸在混合溶剂中的溶解度随直链烷烃的体积分数增大而降低,随温度降低而降低。采用溶剂析出法从溶剂中分离ABB酸时,温度应低于283.15 K,直链烷烃的体积分数大于0.84,直链烷烃使用正己烷。使用修正的λ-h方程关联了实验数据,修正项具有普适性。所有结果均取3次测试结果的平均值。

2-（4-amylbenzoyl ） benzoic acid （ABB acid ） was an important intermediate to prepare 2-amylanthraquinone.It is the key process for 2-amylanthraquinone synthesis to separate pure ABB acid from reaction mixture with a simple and efficient approach.Linear equation between ABB acid mass concentration and peak areas was established by measuring the peak areas of ABB acid standard solutions with different density from 0.9 ×1 0 -9 g/L to 21 ×1 0 -9 g/L using LC.The solubility data measured at various temperatures by equilibria method were acquired when the ABB acid was dissolved in different systems （mixed solvent consist of o-dichlorobenzene and one kind of straight-chain paraffin from n-hexane,n-heptane and n-octane with different volume fraction from 0.750 to 0.875 ）.The solubility of ABB acid in mixed solvents decreases with the volume fraction of straight chain alkanes increases,and decreases with decreasing temperature.The result shows that in terms of ABB acid segregation by adding straight chain alkanes,the temperature should be below 283 .1 5 K,the volume fraction of straight-chain paraffin should be larger than 0.84,and n-hexane is the best choice.The experimental data were correlated by the λ-h equation,which were modified by a universal correction term.All results are the mean values of three test results.