气液色谱法测量芳烃在芳烃衍生物中的活度系数

Activity Coefficients of Aromatic-Aromatic Derivative Systems by Gas-Liquid Chromatography

用气液色谱法测量了C_(6)~C_(8)芳烃在芳烃衍生物中的无限稀活度系数。以Hildebrand-Scatchard-Flory-Huggins公式进行处理,得到了非极性或微极性溶剂的溶解度参数δ,以修正的Hildebrand-Scatchard-Flory-Huggins公式进行处理,得到了芳烃溶质与各极性溶剂相互作用常数ι^(12)。

The thermostat of the gas chromatograph is a well stirred liquid bath, in which the column temperature is to be kept within± 0.01℃.The infinite dilution activity coefficients of C_(6)-C_(8) aromatics, namely, benzene,toluene,ethylbenzene,p-xylene,m-xylene and o-xylene in aromatic derivative, dibenzyl, diphenylmethane, diphenylacetylene, 4-benzylbiphenyl, benzophenone, dibenzylether, diphenylamine, N, N-diphenylformamide and diphenylsulphoxide, all of them contained two or three aromatic rings have been measured.Using Hildebrand-Scatchard-Flory-Huggins formula,the solubility parameters δ of nonpolar and slightly polar solvents, dibenzyl, diphenylmethane, diphenylacetylene and 4-benzylbiphenyl, have been obtained. It has been shown that the measured solubility parameters of the same solvent actually are near a constant, irrespective of what molecular probes have been selected, and the solublity parameters of different solvents only a slightly difference between them have been seen. According to the concept of homomorph, we take 9. 73±0. 01 (at 25℃), the average value of them as the nonpolar solubility parameter of two or three ring aromatics.By means of revised Hildebrand-Scatchard-Flory-Huggins formula,Ln γ_(t)(ln1/r+1-1/r)+V/RT[(δ_(1)-δ_(2))^(2)+2l_(t2)(δ_(1)δ_(2)] and using the value of nonpolar solubility parameter of two ring aromatics mentioned, above, the interaction constants l_(12) between various aromatic solutes and polar solvents, benzophenone, dibenzylether, diphenylamine, N, N-diphenylformamide and diphenylsulphoxide have also been obtained. The calculated interaction constants l_(12) which reflects the degree deviated from Berthelot rule of geometric mean are all positive, and the value of which increase in the order,benzophenone (6.2×10^(-3))≈dibenzylether (7.3×10^(-3))< diphenylamine (9.5 ×10^(-3))