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硝基苯法合成 RT 培司(4-氨基二苯胺)的废水色度高、组分复杂、催化剂四甲基氢氧化铵(TMAOH)难以分离回收。提出采用磁性MCM-41对RT培司废水中有机副产物进行选择性吸附分离。制备的磁性MCM-41样品采用X射线衍射仪(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、N2吸附–脱附和振动样品磁场计(VSM)等手段进行表征。结果表明,磁性MCM-41颗粒的粒径范围为200~300 nm, BET比表面积约为655.2 m2/g,孔径分布为0.5~4 nm,内核铁酸镍的存在使磁性MCM-41具有超顺磁性。吸附研究表明磁性MCM-41对RT培司废水中吩嗪、偶氮苯和苯胺等有机物具有良好吸附作用,经5次吸附磁分离后, RT培司废水中四甲基氢氧化铵能够达到回用要求,吸附后的磁性MCM-41在外加磁场下极易分离。

RT base wastewater has high colority, complex components and troubles to recover the TMAOH catalyst in the process of RT base production by nitrobenzene method. Selectively adsorption and separation of by-product from RT base wastewater with magnetic MCM-41 adsorbent was proposed to recover the TMAOH. The magnetic MCM-41 samples prepared were characterized by transmission electron microscopy (TEM), scanning electron mi-croscope (SEM), X-ray diffraction (XRD), N2 adsorption-desorption vibrating sample magnetometer (VSM). The results showed that the samples had an obvious core-shell structure with an average size of about 200~300 nm in diameter. The N2 adsorption-desorption results showed that the magnetic MCM-41 exhibited micro-mesoporous structure with specific area of 655 m2/g and pore size distribution of 0.5-4 nm. The as-prepared magnetic MCM-41 displayed typical super paramagnetic property due to the inside component of NiFe2O4. The adsorption experiments showed that magnetic MCM-41 selectively adsorbed phenazine, azobenzene and aniline from RT base wastewater. TMAOH aqueous solution could be reused after 5 times adsorptive separation. The synthesized magnetic MCM-41 exhibits high adsorption efficiency and potential applications for the recover for TMAOH catalyst from RT base wastewater with the help of magnetic separation.