Chemical looping combustion (CLC) has great advantages to obtain pure CO 2 from coal combustion flue gas at a manageable cost. CuFe 2 O 4 was put forward as a novel oxygen carrier, which integrated Cu and Fe metals into one oxide matrix with superior characteristics over single metal oxide of either CuO or Fe 2 O 3 and had a high potential to be used in CLC. In this study, the reaction of CuFe 2 O 4 with two Chinese coals of different ranks [Liu Pan Shui (LPS) sub-bituminous coal and Yang Quang (YQ) anthracite] was performed in a thermogravimetric analyzer (TGA). Fourier transform infrared (FTIR) spectroscopy was used to detect in situ the emitted gases from the TGA. Field scanning electron microscopy/energy-dispersive X-ray spectrometry (FSEM/ EDX) was used to study the morphology and elemental compositions present in the solid residues, and the related phases were further identified by X-ray diffraction (XRD). Meanwhile, to explore the reaction mechanisms involved for the reaction of CuFe 2 O 4 with coal, a more realistic simulation system with 376 species was designed for thermodynamic analysis. Through all of these measures, it was found that the reaction of LPS lean coal with CuFe 2 O 4 underwent two distinct reaction stages at 300À600 and 600À850 °C, respectively. At these two reaction stages, CuFe 2 O 4 was dominantly reduced into Cu and Fe 3 O 4 by transfer of the lattice oxygen [O] in CuFe 2 O 4 , and then the formed Fe 3 O 4 was further reduced into Fe 2.962 O 4 . However, above 800 °C, CuFeO 2 and Cu 2 O were produced through direct decomposition of CuFe 2 O 4 into CuFeO 2 and then further partial decomposition of CuFeO 2 into Cu 2 O. Especially, O 2 generated was greatly beneficial to the full conversion of the remaining coal. Different from LPS, the reaction of YQ with CuFe 2 O 4 presented only one discernible reaction stage above 600 °C. Besides Cu and CuFeO 2 , Fe 2.957 O 4 was also generated. Furthermore, four cycles of reduction of CuFe 2 O 4 with H 2 and then oxidation with air displayed a good reaction stability of synthesized CuFe 2 O 4 . However, if coal was used, iron silicates were formed from the interaction of the reduced CuFe 2 O 4 with ash and resulted in the insufficient reoxidation of reduced CuFe 2 O 4 . As such, effective separation of coal ash should be included in the CLC process to ensure the full regeneration of reduced CuFe 2 O 4 .

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The release of inherent potassium may cause severe problems in biomass thermal utilization. A fast-pyrolysis experiment was carried out with rice straw at 400–1000 °C in a fixed-bed reactor. The release of K and Cl to gas and the occurrences of K in residues during devolatilization and char pyrolysis were quantified on the basis of the analysis of rice straw and char samples after devolatilization and pyrolysis for 5 and 30 min. K release after different pyrolysis times all increased with the temperature. The contribution of devolatilization to K release exceeded char pyrolysis above 900 °C. K existed as organic and inorganic K in rice straw with a similar amount, and the original inorganic K is mainly KCl. During devolatilization, organic K dominated K release below 800 °C, while KCl took the place above 900 °C. Significant char K and K2CO3 were generated after devolatilization. During char pyrolysis, KCl dominated K release below 900 °C, while K2CO3 took the place at 1000 °C. Insoluble K silicates were found to form at 900 and 1000 °C, while the char structure restricted the formation amount to about 7%.

A simple copper-catalyzed direct amination of ortho-functionalized haloarenes (2-halobenzoic acid, 2-halobenzamide, and N-(2-bromophenyl)acetamide derivatives) has been developed with use of NaN(3) as the amino source in ethanol, and the corresponding ortho-functionalized aromatic amines were synthesized in good to excellent yields. The protocol undergoes one-pot Ullmann-type coupling of ortho-functionalized haloarenes with NaN(3) to lead to ortho-functionalized azidoarenes, followed by reduction with ethanol.