A synthesis method was introduced for the large-scale preparation of a nano Cu 2 O/Cu-modified activated carbon composite, L-nano Cu 2 O/Cu–C. As the adsorbent, the synthesized composite could efficiently remove radioactive iodide ions (I − ) from simulated water. A lab-scale integrated novel countercurrent two-stage adsorption and membrane separator system was designed to assess the practical application of L-nano Cu 2 O/Cu–C. Stable and high I − removal efficiency was achieved during the operation of the system. The effluent met the water quality requirements, and the membrane fouling rate was lower. This study provides a potential process to treat water contaminated with radioactive I − in practical applications.
Nano Cu 2 O/Cu modified activated carbon composite (nano Cu 2 O/Cu-C) was firstly synthesized by a simple and efficient hydrothermal method and used to adsorb iodide ion (I − ) from simulated radioactive wastewater . Nano Cu 2 O/Cu loaded and uniformly distributed on activated carbon with a diameter of 80–100 nm. The composite exhibited excellent adsorption performance, which was primarily attributable to the synergistic effect of nano Cu 2 O/Cu and activated carbon. Langmuir isotherm and pseudo-second-order kinetic model accurately represented the experimental data of I − adsorption. On the basis of the Langmuir isotherm, the maximum adsorption capacity of I − by nano Cu 2 O/Cu-C was 41.2 mg/g, which is significantly higher than pure nano Cu 2 O and activated carbon. The adsorption was affected only slightly by pH and other interfering ions. Additionally, X-ray photoelectron spectroscopy was used to elucidate the possible adsorption mechanism. This study provides new insight into the fabrication and practical application of high-performance adsorbent in removing radioactive I − from wastewater.
A newly developed adsorbent nano Cu 2 O/Cu-modified activated carbon composite (nano Cu 2 O/Cu-C) was used to remove radioactive iodide ions (I − ) from simulated wastewater. The emphasis of this research is to improve adsorption performance and obtain higher I − removal efficiency compared with the single-stage adsorption. To fully develop the amount of adsorption by nano Cu 2 O/Cu-C, and to increase the decontamination factor (DF) of I − , an improved countercurrent two-stage adsorption (ICTA) process was introduced. In the ICTA process, measures dealing with desorption of loaded adsorbent in the stage-two adsorption were taken and more extensive application of countercurrent two-stage adsorption (CTA) process could be made after the improvement to ICTA process in this study. Furthermore, in order to analyze the process and determine the I − concentration in the effluent, a calculation method was devised based on the Langmuir isotherm equations and adsorption accumulation principle. The mean DFs were 177, 166, and 89.7, respectively, when the initial I − concentrations were 5.00, 10.0, and 20.0 mg/L; and the adsorbent dosage was 1.25 g/L. These results were approximately 8.76, 8.97, and 6.79 times higher, respectively, than with conventional single-stage adsorption. The experimental values of the I − concentration were higher than the calculated ones, which could be ascribed to desorption of the residual loaded adsorbent and formation of CuI in the adsorption at stage 1. Formation of CuI in the adsorption at stage 1 was considered to be the predominant reason.
危险品化学品经营许可证（带存储）