One-step preparation of magnetically responsive materials from non-magnetic powders

A simple procedure has been developed for the conversion of non-magnetic powder materials into their magnetic derivatives, which is based on the mixing of the material to be modified with water based magnetic fluid. After drying, aggregates of maghemite were deposited on the treated material, enabling its magnetic separation. In this paper we provide two examples of low-cost non-magnetic materials suitable for this type of simple one-step magnetic modification. Magnetically modified spent tea leaves efficiently adsorbed organic dyes; high maximum adsorption capacity (up to 100 mg g− 1) was achieved. Magnetic montmorillonite was used as a carrier for the immobilization of lipase and β-galactosidase; immobilized enzymes showed long-term stability without leaching of enzyme from the support and enabled their repeated use without significant loss of activity.

A simple procedure has been developed for magnetization of non-magnetic powder materials using water based magnetic fluid. After drying, aggregates of maghemite nanoparticles were deposited on the treated material, enabling its magnetic separation. Magnetically modified spent tea leaves efficiently adsorbed organic dyes while magnetic montmorillonite was used as a carrier for the immobilization of lipase and β-galactosidase.Figure optionsDownload as PowerPoint slideHighlights
► Non-magnetic powders were magnetically modified with water-based magnetic fluid.
► Magnetically modified spent tea leaves were used as an adsorbent for dyes removal.
► Magnetically modified montmorillonite was used as a carrier for enzyme immobilization.