摘要：

Coconut husk (CH), consisting of coconut pith (CP) and coconut fiber (CF) is abundant and cheap, and has the potential to be used as adsorbent for elemental mercury (Hg0) removal. CP and CF surfaces were modified by mercerization and bleaching methods and characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and analysis of moisture and ash. The elemental mercury adsorption measurements were carried out at the following conditions: initial Hg0 concentration, 200±20μg/m3; bed temperature, 50 ± 1°C; N2 flow rate, 0.05L/min; mass of adsorbent, 50mg; and adsorbent particle size of between 75 and 100μm. The surface morphology and surface functional groups of adsorbents significantly changed after treatments and resulted in different Hg0 adsorption performances. The highest Hg0 adsorption capacity was observed for CP-NaOH (956.282ng/g), followed by CP-Pristine (730.250ng/g), CF-NaOCl (639.948ng/g), CF-H2O2 (634.347ng/g), CF-NaOH (611.678ng/g), CF-H2O2 (531.277ng/g), CP-NaOCl (501.126ng/g), and CF (431.773ng/g). The experimental breakthrough data for all the adsorbents produced a good fit to the pseudo-second order kinetic model.

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