Formaldehyde is an important chemical that is mostly handled in aqueous solutions, which generally also contain methanol; furthermore, also solutions of formaldehyde in other alcohols are used. The density of these solutions is an important thermophysical property. The available models of the density of formaldehyde-containing solutions, however, all have shortcomings, such as a poor accuracy or a limited range of applicability. Therefore, in the present work, a new model of the density in systems of the type (formaldehyde + water + alcohol) was developed. The alcohols that are presently included in the new model are methanol, 1-propanol, and isoprenol; an extension to other alcohols is straightforward. The model was developed using literature data and extensive new density data measured in this work covering binary, ternary, and quarternary solutions of formaldehyde in water, methanol, 1-propanol, and isoprenol at temperatures of $283-333$283−333$283-333$ K and formaldehyde concentrations of 0.06 − 0.30 g g⁻¹.

中文翻译：

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甲醛在水和醇中的溶液密度

甲醛是一种重要的化学物质，主要在水溶液中处理，一般还含有甲醇；此外，还使用在其他醇中的甲醛溶液。这些溶液的密度是一个重要的热物理性质。然而，现有的含甲醛溶液密度模型均存在准确性差或适用范围有限等缺点。因此，在目前的工作中，开发了一种新的系统密度模型（甲醛 + 水 + 酒精）。目前包含在新模型中的醇是甲醇、1-丙醇和异戊二烯醇；扩展到其他醇类很简单。该模型是使用文献数据和在这项工作中测量的广泛的新密度数据开发的，涵盖二元、三元、$283-333$283 - 333$283-333$K 和甲醛浓度为 0.06 - 0.30 gg ^-1。