Magnetic separation of ferromagnetic particles from fine dust recovered from airbag during printed circuit board (PCB) comminution appears quite rational, but under magnetic field, dust particle separation is problematic due to diverse particle morphology, electrostatics, induced magnetism and does not wet. These effects frustrate PCB dust magnetic separation, wet or dry. Chemical conditioning of the PCB dust pulp with octyl phenol ethoxylate (OPE) was conceived to combat these effects by altering the surface tension of water to wet and disperse the dust particles for efficient wet magnetic separation. At optimum OPE concentration used, which gave 56 dynes/cm solution, Fe and Ni recoveries in the 150 – 212 µm dust, were 97 and 94 %, respectively, under wet high intensity magnet (3150 Gauss); these dropped to 92 and 85 %, under low intensity magnet (1370 Gauss) , but misplacement of paramagnetic elements such as gold, copper reduced from 22 % to 5.4 % Au and 5.4 % to 2.2% Cu. The best Separation Efficiency, considering the major economic elements, is up to 83 % in a single roughing step under the low intensity wet magnetic separation. With evolution in PCB dust complex material streams for beneficiation, chemical conditioning has appeared as a vital factor to make wet magnetic separation effective.

铁磁性颗粒与印刷电路板（PCB）粉碎过程中从安全气囊中回收的细小灰尘的磁分离看来是很合理的，但是在磁场下，由于各种不同的颗粒形态，静电，感应磁性和不润湿，使得灰尘颗粒分离存在问题。这些影响使湿或干的PCB灰尘磁分离变得困难。人们认为，通过改变水的表面张力来润湿和分散灰尘颗粒以有效地进行湿式磁选，可以用辛基酚乙氧基化物（OPE）对PCB尘浆进行化学调理，以克服这些影响。在最佳的OPE浓度下（溶液为56达因/厘米），在湿式高强度磁体（3150高斯）下，在150-212 µm的粉尘中，铁和镍的回收率分别为97％和94％。这些下降到92％和85％，在低强度磁体（1370高斯）下，但是诸如金，铜之类的顺磁性元素的错位从22％的Au减少到5.4％，而Cu的含量从5.4％减少到2.2％。考虑到主要的经济因素，在低强度湿磁分离条件下，一次粗加工步骤的最佳分离效率最高可达83％。随着PCB粉尘复杂物料流的发展，化学处理已成为使湿式磁选有效的重要因素。