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Several kinds of spherical cysteine grafted cobalt/manganese imprinted crosslinking chitosan spheres were synthesized for Mn2+ and Co2+ removal, in which Mn2+ and Co2+ were used separately or together as imprinting ions. Structures of the adsorbents were analyzed utilizing the techniques of SEM and FTIR. The effects of initial pH, contact time, presence of other cations, initial Mn2+ and Co2+ concentration on adsorption were investigated. Furthermore, adsorption kinetics and isotherm were studied, which showed sorption data fitted to pseudo-second-order and Langmuir models for both Mn2+ and Co2+. The overall results indicated the possibility of using Cys–Co/Mn–CCTS–2 for efficient removal of Mn2+ and Co2+ from dilute low-level radioactive liquid waste.

Bi-functional mesoporsous silica adsorbents, functionalized via the introduction of chelating agents (mercaptopropyl and aminopropyl groups) were prepared to adsorb Co2+ and Mn2+ in dilute solutions. The molar ratio of MPTMS/APTMS in grafting process seemed to have great effected on the mesostructure of adsorbents, and the appropriate value was considered to be 2/1. The modified silica gels at that ratio showed well-ordered property as well as its high infinity of the two metal ions. The pseudo-second-order equation was applied to describe the adsorption kinetics. And the influence of interferential ions Ca2+ and Mg2+ was also studied.

The feasibility of using nonwoven polypropylene fiber (NWPP) as the filter media to treat oil-in-water emulsion was studied. Both static adsorption experiments and dynamic filtration in coalescence bed were made. Due to the hydrophobic property of NWPP, the oil adsorption happened immediately when contacted with NWPP. The equilibrium was achieved after 50min adsorption. The Freundlich isotherm fits the experimental data well. The data was analyzed with three adsorption kinetic models: the pseudo first order, second order adsorption kinetics as well as the intra-particle diffusion models. The results showed that the second order adsorption kinetic was more accurate to correlate the experimental data. After the dynamic filtration processes using 4.0g NWPP, the oil removal efficiency could achieve 95%. It also found that the low flow rates would be better to treat oil-in-water emulsion in dynamic condition using NWPP as the filter media.

Two spherical composite adsorbents namely polyacrylonitrilepotassium cobalt hexacyanoferrates (PAN-KCoCF) and polyacrylonitrilepotassium nickel hexacyanoferrates (PAN-KNiCF) were synthesized. The effects of liquid flow rate, bed height and presence of other cations on the adsorption of cesium were investigated by conducting fixed-bed columns. The results showed that the column performed well at lowest flow rate for PAN-KNiCF. Flow rate examined had little influence on the adsorption of PAN-KCoCF. The breakthrough time decreased with decreasing bed height for both PAN-KCoCF and PAN-KNiCF. In addition, the existence of K+, Na+, NH4+, Ca2+and Mg2+in solution caused a reduction of maximum adsorption capacity for both of the composites. The bed depth service time (BDST) model and the Thomas model were used to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.