The debromination of brominated epoxy resins (BERs) from waste printed circuit boards (WPCBs) is of great challenge due to its high structural stability. An enhanced subcritical water (SCW) process with alkaline additive is proposed for efficient debromination of BERs, and the mechanism of alkaline additive on bromine removal has been investigated. More than 95.11% of bromine is removed under the optimal conditions. Both enhanced fiberglass destruction and BERs degradation contribute to the efficient debromination process. Structure of Ca−Al, Si−O, and Al−O bonds in fiberglass is destroyed by alkaline corrosion, releasing BERs into the solution and facilitating the debromination process. Meanwhile, phenol, 2-bromophenol and catechol are the main products of BERs degradation. Nucleophilic substitution reaction by the bimolecular process dominantly contribute to the debromination. The energy barrier of the bimolecular process is only 15.9 kcal/mol, which is much lower than that of the direct dissociation energy of C−Br bond (168.3 kcal/mol). Ion association of KOH is weaker than that of NaOH in the alkaline-enhanced SCW process due to the difference of cation radius, proved by ab initio molecular dynamics simulation. An efficient approach for WPCBs debromination under mild conditions has been proposed.

从废印刷电路板（WPCB）中脱溴溴化环氧树脂（BER）的过程具有很高的结构稳定性，这是一个巨大的挑战。有人提出了一种使用碱性添加剂的增强亚临界水（SCW）工艺，以有效地脱除BER，并且研究了碱性添加剂对溴的去除机理。在最佳条件下，可去除95.11％以上的溴。玻璃纤维破坏的增强和BER的降解都有助于有效的脱溴过程。玻璃纤维中的Ca-Al，Si-O和Al-O键的结构会被碱腐蚀破坏，从而将BERs释放到溶液中并促进脱溴过程。同时，苯酚，2-溴苯酚和儿茶酚是BERs降解的主要产物。通过双分子过程的亲核取代反应主要有助于脱溴。双分子过程的能垒仅为15.9 kcal / mol，远低于C-Br键的直接离解能（168.3 kcal / mol）。从头算分子动力学模拟证明，由于阳离子半径的不同，在碱增强的SCW工艺中，KOH的离子缔合比NaOH弱。已经提出了在温和条件下对WPCB脱溴的有效方法。从头算分子动力学模拟证明。已经提出了在温和条件下对WPCB脱溴的有效方法。从头算分子动力学模拟证明。已经提出了在温和条件下对WPCB脱溴的有效方法。