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Graphical abstract Highlights • A predictive model for fluidized adsorption was developed by dimensional analysis. • The model predicted adsorption performance well under different operating conditions. • Effect of superficial liquid velocity was the combination of Re and void fraction. Abstract In this study, we developed a predictive model for quantitatively assessing the copper ion (Cu(II)) removal performance of 001∗7 resin in a liquid–solid fluidized bed reactor. The model was developed using the dimensional analysis approach based on dynamic experimental data. Experiments were conducted to evaluate the effects of operational variables (adsorbent dosage, initial solution concentration, and superficial liquid velocity) on the Cu(II) removal performance. The model predictions were in good agreement with the experimental data, thereby indicating that the model could accurately describe the removal of Cu(II) by fluidized adsorption. A model that obtains better predictions could help to optimize the operational variables in implementations of the fluidized adsorption technique for wastewater treatment. The model showed that increasing the 001∗7 resin dosage and decreasing the superficial liquid velocity could achieve a higher Cu(II) uptake capacity. In order to verify the theoretical rationality of the model, we clarified the effect of the superficial liquid velocity on the Cu(II) removal. A larger superficial liquid velocity yielded a higher Reynolds number which could enhanced the fluidized adsorption, but led to a higher void fraction which could weaken the adsorption. Thus, the effect of the superficial liquid velocity on the Cu(II) removal was modeled as a combination of the Reynolds number and void fraction. [ABSTRACT FROM AUTHOR]

To guide the practical application of fibrous materials in wastewater treatment, this study explored the engineering design of fixed bed adsorption technique by using carboxyl-modified jute fiber (CMJF) for copper ion (Cu(II)) removal from aqueous solution. The study, conducted by means of adsorption experiments in a column with a fixed bed of sorbent, investigated the effects of the CMJF sorbent dosage, the flow rate and the initial Cu(II) concentration on the corresponding breakthrough curves and compared the dynamic adsorption performance of raw and modified jute in the same process conditions. Compared with the fixed bed of raw jute fiber, the CMJF sorbent exhibited a breakthrough time about 3.2 times longer and a dynamic adsorption capacity roughly 4.2 times higher at the optimal conditions (packing height of 8 cm, flow rate of 17.45 cm/min and initial concentration of 100 mg/L). The dynamic adsorption capacity, 50% breakthrough time and 10% breakthrough time could be well predicted by Thomas, Yoon–Nelson and Bed Depth Service Time (BDST) models, respectively. Besides, these dynamic models well described the fixed bed adsorption behavior, and the CMJF exhibited better fixed bed adsorption performance than raw jute. [ABSTRACT FROM AUTHOR]

Pristine rice husk (RH), a kind of agricultural waste based biosorbent, was chemically modified by introducing sulfur-bearing groups with the CS 2 treatment under caustic medium. Using response surface methodology (RSM), the interactive effects of three preparation variables on the cadmium uptake and material yield of xanthate-modified rick husk (RH-X) were investigated, and two quadratic regression models were developed to correlate the preparation parameters to the two responses. Through process optimization, the optimal RH-X was finally obtained under the optimum synthesis conditions (i.e., 1.00 CS 2 -RH ratio, 60.00 min xanthation contact time and 18.50 °C xanthation temperature), resulting in 138.85 mg g −1 of cadmium uptake, and 68.63% of RH-X yield, strictly similar to the values predicted from the models, with extremely small errors of 0.85 and 0.96%, respectively. Overall, cheap and abundant raw materials, low-cost and easily-controlled preparation and excellent cadmium adsorption ability can make RH-X a preferred biosorbent for wastewater decontamination. [ABSTRACT FROM AUTHOR]