摘要
提出分子膜阻蒸发技术,并制备一种挥发抑制剂,可在甲醛溶液表面自行铺展成膜,有效抑制挥发.考察了温度对甲醛溶液挥发特性和抑制剂阻蒸发效果的影响,并采用密度泛函理论中的B3LYP方法模拟优化了气液界面甲醛—水分子团簇结构,进行能量障碍理论和热力学分析.研究结果表明,挥发过程中溶液浓度变化与温度呈线性负相关,整个挥发过程明显分为3个区间;制备的抑制剂能够在液体表面快速有序分布,于25~50℃下抑制率高达99%,溶液传质系数值几乎为0;理论计算结果很好地解释了甲醛溶液气液界面挥发及抑制机理.
The technology of evaporation inhibition by molecular film was put forward and a new kind of formaldehyde solution evaporation inhibitor was prepared. It could spontaneously and quickly spread on the surface of solution; effectively inhibit volatilization of formaldehyde solution. The effects of temperature on the volatilization characteristics of formaldehyde solution and the evaporation resistance of inhibitor were investigated. The structures of formaldehyde-water clusters at gas-liquid interface was optimized by the B3LYP method of density functional theo ry, the energy barrier theory analysis and thermodynamic analysis were put forward. The results indicated that the concentration of formaldehyde soIution had negative linear relationship with the temperature; there were three obvious intervals in the whole process of volatilization. The inhibitor prepared could rapidly and orderly distributed on the liquid surface, its inhibition rate was up to 99% at 25-50 ℃ and the mass transfer coefficient of formaldehyde solution was near-zero. The volatilization/inhibition mechanism of formaldehyde solution at gas--liquid interface was well explained by the theoretical calculation.
出处
《消防科学与技术》
CAS
北大核心
2015年第6期701-705,共5页
Fire Science and Technology
基金
国家自然科学基金资助项目(21107080)
关键词
甲醛溶液
挥发抑制剂
传质系数
分子模拟
密度泛函理论
formaldehyde solution
volatilization inhibitor
mass transfer coefficientl molecular simulation
density functional theory