A Highly Efficient Adsorbent Cu-Perusian Blue@Nanodiamond for Cesium in Diluted Artificial Seawater and Soil-Treated Wastewater

A new adsorbent Cu-Perussian blue@Nanodiamond (Cu-PB@DND) for Cs(+) removal was prepared and characterized with IR, SEM, X-ray diffraction, particle size analysis, and zeta-potential. The adsorbent consists of a core of aggregated detonation nanodiamond (DND) particles with the surface treated with Cu-PB. Cesium adsorption was studied in two modes; a co-precipitation mode and a batch mode. In the co-precipitation mode, DND, CuCl(2), and K(4)[Fe(CN)(6)] were added sequentially to a Cs(+) solution in diluted artificial seawater. In the batch mode, adsorbent Cu-PB@DND was dispersed into a Cs(+) solution with stirring. The distribution coefficient (K(d)) of the co-precipitation mode was 8.8 × 10(7) (mL/g) at Cs(+) 6.6 ppm in 0.07% seawater. The K(d) value of the batch mode was 1.3 × 10(6) (mL/g). Precipitation of Cs(+)-incorporated particles was complete, and post filtration was not necessary. Excess copper and iron ions were completely removed and were not detected in the supernatant. The adsorption data for Cu-PB@DND were analyzed by assuming Langmuir isotherm and a good fit was obtained with a maximum adsorption capacity Q(max) of 759 mg/g. The co-precipitation method was also applied to soil-treated wastewater.