Nicotinamide is an organic acid belonging to the vitamin B3 family. This material holds high nutritional importance especially related to different aspects of health and tissue recovery. The development of alternative strategies for its production depends on studies concerning experiments and modeling. Solubility experiments provide data about the distribution of a target material under solid-liquid equilibrium. This information coupled with mathematical models allows the determination of interaction parameters that can be used both for scientific and industrial improvements. In this work, the solubility of nicotinamide was experimentally studied in binary liquid mixtures formed by methanol + ethanol and methanol + 2-propanol covering the entire molar fraction of the binary liquid solution. The solubility was gravimetrically determined in the temperature range from 293.2 K to 323.2 K. The experimental results were used to perform the parameters optimization for the UNIFAC and UNIFAC-DO models. Furthermore, the COSMO-SAC and COSMO-UNIFAC models (and variants) were used to predict the solid-liquid equilibrium. The model UNIFAC-DO has presented the most reliable results, providing the sum of the absolute errors (SAE) and the sum of the relative errors (SRE) of 0.2448 and 11.4634, respectively, while the original UNIFAC presented 1.5636 and 28.2620, and the COSMO-SAC-based methods presented, as best result, 4.7228 and 75.0050.

烟酰胺是一种属于维生素B3家族的有机酸。这种材料具有很高的营养重要性，尤其是与健康和组织恢复的不同方面有关。替代性生产策略的发展取决于有关实验和建模的研究。溶解度实验提供了在固液平衡下目标物质分布的数据。该信息与数学模型相结合，可以确定可用于科学和工业改进的相互作用参数。在这项工作中，对烟酰胺在由甲醇+乙醇和甲醇+ 2-丙醇组成的二元液体混合物中进行了实验研究，该混合物覆盖了二元液体溶液的整个摩尔分数。溶解度是在293.2 K至323.2 K的温度范围内通过重量分析确定的。实验结果用于对UNIFAC和UNIFAC-DO模型进行参数优化。此外，COSMO-SAC和COSMO-UNIFAC模型（和变体）用于预测固液平衡。UNIFAC-DO模型提供了最可靠的结果，分别提供了绝对误差之和（SAE）和相对误差之和（SRE）分别为0.2448和11.4634，而原始UNIFAC分别为1.5636和28.2620，以及基于COSMO-SAC的方法的最佳结果为4.7228和75.0050。COSMO-SAC和COSMO-UNIFAC模型（及其变体）用于预测固液平衡。UNIFAC-DO模型提供了最可靠的结果，分别提供了绝对误差之和（SAE）和相对误差之和（SRE）分别为0.2448和11.4634，而原始UNIFAC分别为1.5636和28.2620，以及基于COSMO-SAC的方法的最佳结果为4.7228和75.0050。COSMO-SAC和COSMO-UNIFAC模型（及其变体）用于预测固液平衡。UNIFAC-DO模型提供了最可靠的结果，分别提供了绝对误差之和（SAE）和相对误差之和（SRE）分别为0.2448和11.4634，而原始UNIFAC分别为1.5636和28.2620，以及基于COSMO-SAC的方法的最佳结果为4.7228和75.0050。