近日，德国亚琛工业大学Stefan Pielsticker团队报道了甲基丙烯酸甲酯气相分解动力学模型及其对聚甲基丙烯酸甲酯热解收率的影响。相关论文发表在2026年5月28日出版的《颗粒学报》杂志上。

将聚甲基丙烯酸甲酯（PMMA）化学回收为其单体甲基丙烯酸甲酯（MMA），需要在主链解聚反应与抑制二次气相反应之间取得平衡。

研究组利用在线傅里叶变换红外光谱，在623 K至1073 K的温度范围内，对流化床反应器中非氧化条件下的MMA分解行为进行了探究。实验结果显示产物选择性发生显著变化：低温有利于低能脱羧路径（生成CO₂和甲醇），而高温则促进自由基裂解路径（生成CO和轻烃）。为此，研究组采用了一个双竞争反应模型（CRM），该模型优于传统的单一一级反应模型。

CRM模型确定了两个不同的活化能：脱羧反应的E_a,1 = 76.5 kJ·mol^-1，裂解反应的E_a,2 = 269.9 kJ·mo^l-1。研究进一步表明，传统的顺序分解模型（PMMA → MMA → 轻质气体）在低温下会高估单体的产率。通过引入直接固相到气相的侧链断裂路径，并结合多体积反应器流体动力学，模型的预测准确性得到显著提高。该集成模型确定了一个约723 K附近的最佳回收温度窗口，在此条件下MMA产率可超过95%。

附：英文原文

Title: Kinetic Modeling of Methyl Methacrylate Gas-Phase Decomposition and its Impact on Polymethyl Methacrylate Pyrolysis Yields

Author: anonymous

Issue&Volume: 2026/05/28

Abstract: Chemical recycling of polymethyl methacrylate (PMMA) to its monomer, methyl methacrylate (MMA), requires balancing primary depolymerization with the suppression of secondary gas-phase reactions. This study investigates non-oxidative MMA decomposition in a fluidized bed reactor across a temperature range of 623K to 1073K using online FTIR spectroscopy. Experimental results reveal a significant shift in product selectivity: low temperatures favor a low-energy decarboxylation pathway (yielding CO2 and methanol), while high temperatures promote radical cracking (yielding CO and light hydrocarbons). To describe this, a two-competing-reactions model (CRM) is used, outperforming the traditional single first-order approaches. The CRM identifies two distinct activation energies: Ea,1 = 76.5kJmol1 for decarboxylation and Ea,2 = 269.9kJmol1 for cracking. The research further demonstrates that the classical sequential decomposition model (PMMA → MMA → light gases) overpredicts monomer yields at low temperatures. By integrating a direct solid-to-gas pathway to account for side-chain break-off and incorporating multi-volume reactor hydrodynamics, the model’s predictive accuracy significantly improved. This integrated framework identifies an optimal recovery window near 723K, achieving MMA yields over 95%.

DOI: 10.1016/j.partic.2026.05.011

Source: https://www.sciencedirect.com/science/article/pii/S167420012600194X