许多烃及其含氧衍生物属于GHS标签分类中的物理危险, 即在稳定的储存环境中也会发生热分解甚至燃烧、爆炸, 对环境、人体造成难以恢复的伤害。因此, 快速精准评估此类物质分解引发的事故后果是工程领域中常面临的实际问题。该研究提出了一种引入小分子烃多组分的替代模型, 用于表征易燃易爆危化品中烃类含氧衍生物的燃烧特性, 实现大分子复杂物质燃烧反应动力学模型构建, 从而反映危化品事故后果的特征。研究结果表明, 醇类与醚类替代模型的必含组分基本一致, 均为CH₄、C₂H₆、C₃H₈、C₄H₁₀, 并且其最佳替代方案具有极高的重合性, 呋喃类物质多组分替代模型包括CH₄、i-C₄H₈和C₄H₁₀, 分析结果与高温热裂解实验相符。该研究为构建烃及其含氧衍生物的燃烧反应动力学模型提供了新思路。

Objective: Hydrocarbons and their oxygen-containing derivatives are often used as fuels or fuel substitutes, most of which are prone to spontaneous combustion. During combustion, high-temperature flames and toxic gases (e.g., carbon oxides and nitrogen oxides) are produced, causing irreversible damage to the surrounding organisms, water bodies, soil, and air. Therefore, quickly and accurately assessing the consequences of accidents caused by their decomposition is a common practical problem in engineering. Methods: This study aimed to characterize the combustion properties of hydrocarbon oxygen-containing derivatives in flammable and explosive hazardous chemicals. A substitute model incorporating multiple components of small molecules was proposed. Based on the ratio of enthalpy changes, the components and proportion coefficients for each multicomponent substitution model were determined, and a library of 120 models was constructed. The following combustion characteristic parameters were selected as indicators: the maximum net heat release rate difference of gas phase reactions, the highest temperature difference of the adiabatic flame, the flame propagation speed difference, the mean square error (MSE) of the H mole fraction, and the MSE of the O₂ mole fraction. The combustion characteristic difference library was comprehensively evaluated using the G1 and TOPSIS methods, along with an improved CRITIC comprehensive weighting approach. The index matching accuracy between small-molecule hydrocarbon substitution models and complex molecular substances was calculated. From this, the optimal substitution schemes and substitution model sets of the same type of substances were selected. Furthermore, the intersection components of the alternative model sets were used as a simple alternative to simulate the combustion reaction kinetics of complex molecular substances. The rationality of these alternative models was verified through high-temperature pyrolysis experiments. Eventually, an alternative model for the combustion reactions of large-molecule complex substances was constructed, characterizing the consequences of hazardous chemical accidents. Results: (1) Using the selected combustion characteristic indicators effectively identified the best alternative models. (2) The substitution models for alcohols and ethers shared essentially the same components, including: CH₄, C₂H₆, C₃H₈, and C₄H₁₀, and exhibited a very high degree of overlap in their best alternative solutions. (3) The multicomponent substitution model for furan compounds included CH₄, i-C₄H₈, and C₄H₁₀. The analysis results are in agreement with the high-temperature pyrolysis tests. (4) The best alternative model demonstrated low sensitivity to the weights of each indicator. Therefore, the intersection of the alternative models serves as a mandatory and highly reliable component. Conclusions: The multicomponent, small-molecule hydrocarbon substitution model adopted does not yet encompass all categories of hydrocarbon oxygen-containing derivatives. Some results need further experimental validation. Nonetheless, the research results provide new ideas for constructing combustion reaction kinetic models of hydrocarbons and their oxygen-containing derivatives. This approach enables highly accurate prediction of the consequences of an accident involving complex mixed components (such as gasoline and diesel derived from petroleum).