Modifying humic acids on magnetite nanoparticles to sorption of p-chlorophenol

Modifying humic acids on magnetite nanoparticles (M/HA) to sorption of p-chlorophenol have been studied. The M/HA was synthesized by coprecipitation method in alkaline condition using ammonium hydroxide and humic acids (HA) was isolated from peat soil in Samarinda, East Kalimantan. Modification of M/HA was prepared using mass ratios of M and HA = 20:1, 20:2, 20:4, 20:6. The four adsorbents of M/HA were characterized by determination of pH point zero charge (pHPZC), magnetic properties by vibrating sample magnetometer and morphology were observed by scanning electron microscopy. The result showed that sorption of p-chlorophenol on four of M/HA materials was optimum at pH 3.0 and fitted well to pseudo second-order kinetic models and Langmuir isotherm. The adsorption capacity of M/HA between 0.27-0.57 mmol/g. Generally, the performance of four M/HA materials to sorption of p-chlorophenol was M/HA=20:6 > M/HA=20:4 > M/HA=20:2 > M/HA=20:1.