关键词: 磁性吸附剂;络合分离;烯烃/烷烃;平衡吸附量;吸附选择性

Abstract: AgNO3/MCM-41/NiFe2 O4 was designed and synthesized via the incipient wetness impregnation. It served as a magnetic complex separation adsorbent and could be used to separate the long-chain olefin/paraffin mixtures. The samples were characterized by powder X-ray diffraction analysis ( XRD ) , nitrogen adsorption-desorption analysis, Fourier transform infrared spectroscopy ( FTIR ) , vibrating sample magnetometer ( VSM) and etc. The tests show that the obtained products are composed of NiFe2 O4 with spinel structure and MCM-41 with hexagonal arrangement of unidimensional mesopores. AgNO3 is dispersed in a monolayer in the channel. The optimal loading amounts of AgNO3 is 0. 2 g/g magnetic carrier. The specific surface area and most probable pore size are 717. 89 m2/g, 2. 94 nm. For the C11 olefin/C11 paraffin mixtures, adsorption behaviours of C11 olefin on magnetic adsorbent were investigated. Results show that adsorbents have preferential adsorption for long-chain olefins. The one-stage equilibrium adsorption capacity and adsorption time are 2. 14 g/g, 100 min respectively. Adsorptive selectivity and magnetic recovery of adsorbents after reuse were studied. After repeated use ten times, the recovery was up to 98. 9% and the selectivity of olefin decreased slightly. But the changes still can satisfied requirements for olefin adsorbed selectively.

Key words: magnetic adsorbent;complex formation separation;olefin/paraffin;equilibrium adsorption capacity;adsorptive selectivity