Given the fact that the basicity of imidazolate was higher than that of acetate, imidazolate-based ionic liquids (ILs) were developed to be studied. By combining six different cations, including traditional cation, functionalized cation, and dication, together with imidazolate, a series of ILs were prepared and found to be effective for CO2 capture. The mechanism of the studied ILs was proposed as the formation of the carboxylation reactions on C2 position of the imidazolium rings. A strong interaction between the newly formed carboxylate portion of the zwitterion and the C2–H proton of another cation was also formed, leading to a 0.5 molar ratios of CO2 to IL. In addition, the CO2 absorption capacity of dicationic IL was 1.0 molar ratio, twice that of the monocationic analogue. Significantly, an improvement on absorption result was exhibited by the amino-functionalized IL, but similar performance was not observed in the hydroxyl-functionalized one. The effects of operating pressure and temperature on CO2 absorption were also discussed.

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In this study, the combined use of Fenton reagent and ultrasound to the pretreatment of microcrystalline cellulose (MCC) for subsequent enzyme hydrolysis was investigated. The morphological analysis showed that the aspect ratio of MCC was greatly reduced after pretreatment. The X-ray diffraction (XRD) and degree of polymerization (DP) analyses showed that Fenton reagent was more efficient in decreasing the crystallinity of MCC while ultrasound was more efficient in decreasing the DP of MCC. The combination of Fenton reaction and ultrasound, which produced the lowest crystallinity (84.8 ± 0.2%) and DP (124.7 ± 0.6) of MCC and the highest yield of reducing sugar (22.9 ± 0.3 g/100 g), provides a promising pretreatment process for MCC depolymerization.

The leaching kinetics of K-feldspar in HSO-CaF system with the assistant of ultrasound was investigated. The effects of various factors, such as sulfuric acid concentration, liquid-to-solid ratio, CaF dosage and leaching temperature were comprehensively studied. The dissolution fraction of potassium can reach more than 83% under the optimum operation conditions with ultrasound. Because of the cavitation effect, the intensified effect with ultrasound has more obvious at lower temperature than higher temperature. The leaching kinetics of K-feldspar with and without ultrasound was successfully modeled by a classic shrinking core model with the product layer diffusion as the rate-controlling step. The activation energies over the temperature range from 60 to 90°C with and without ultrasound were found to be 55.67kJmol and 72.33kJmol, respectively. It was found that the rate constant increases greatly in the presence of ultrasound due to the decreased apparent activation energy, resulting in the improved dissolution fraction of potassium.

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