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The Box–Behnken Design of the response surface methodology was employed to optimize four most important adsorption parameters (initial arsenic concentration, pH, adsorption temperature and time) and to investigate the interactive effects of these variables on arsenic(V) adsorption capacity of mesoporous alumina (MA). According to analysis of variance (ANOVA) and response surface analyses, the experiment data were excellent fitted to the quadratic model, and the interactive influence of initial concentration and pH on As(V) adsorption capacity was highly significant. The predicted maximum adsorption capacity was about 39.06 mg/g, and the corresponding optimal parameters of adsorption process were listed as below: time 720 min, temperature 52.8 °C, initial pH 3.9 and initial concentration 130 mg/L. Based on the results of arsenate species definition, FT-IR and pH change, As(V) adsorption mechanisms were proposed as follows: (1) at pH 2.0, H3AsO4 and H2AsO4− were adsorbed via hydrogen bond and electrostatic interaction, respectively; (2) at pH 6.6, arsenic species (H2AsO4− and HAsO42−) were removed via adsorption and ion exchange, (3) at pH 10.0, HAsO42− was adsorbed by MA via ion exchange together with adsorption, while AsO43− was removed by ion exchange.

Experiments were conducted to investigate and control pollutant emission from incineration of Sedum plumbizincicola plants on a laboratory scale using an entrained flow tube furnace. Without control technologies, the flue gas contained 0.101 mg Nm(-3) of Cd, 46.4 mg Nm(-3) of Zn, 553 mg Nm(-3) of NOx, 131 pg Nm(-3) of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/Fs) and 35.4 mg Nm(-3) of polycyclic aromatic hydrocarbons (PAHs). In pollutants control experiments. Al2O3, CaO, and kaolin were compared as adsorbents and activated carbon was used as an end-of-pipe method for the capture of pollutants. Kaolin, the most effective of the three adsorbents, removed 91.2% of the Cd in flue gas. While 97.6% of the Cd and 99.6% of the PAHs were removed by activated carbon. Incineration may therefore be regarded as a viable option for the safe disposal of the biomass of the zinc and cadmium hyperaccumulator species S. plumbizincicola.