Synthesis of magnetically separable adsorbents through the incorporation of protected nickel nanoparticles in an activated carbon

We present a simple and versatile route to prepare magnetically separable porous carbons from commercial activated carbons. The magnetic properties of the composite are provided by nickel nanoparticles (around 8-15 nm), which are produced within the porous network by means of the thermal treatment at 600 °C of an activated carbon impregnated with a nickel salt and sucrose. This synthetic strategy allows the magnetic nanoparticles to be protected against acid attack. The magnetic composite thus obtained exhibits a large surface area and a high pore volume. An important advantage of this composite is that exhibits, at room temperature, low coercivity (∼0.1 kOe), allowing it to be easily manipulated by means of low external magnetic fields.