@article{scholars16062,
            year = {2022},
           title = {Enhanced activity and stability of SO42{\^a}??/ZrO2 by addition of Cu combined with CuZnOZrO2 for direct synthesis of dimethyl ether from CO2 hydrogenation},
             doi = {10.1016/j.ijhydene.2022.03.150},
          volume = {47},
         journal = {International Journal of Hydrogen Energy},
           pages = {41374--41385},
       publisher = {Elsevier Ltd},
          number = {98},
            note = {cited By 8},
          author = {Witoon, T. and Numpilai, T. and Dolsiririttigul, N. and Chanlek, N. and Poo-arporn, Y. and Cheng, C. K. and Ayodele, B. V. and Chareonpanich, M. and Limtrakul, J.},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85127736164&doi=10.1016\%2fj.ijhydene.2022.03.150&partnerID=40&md5=39c32fac4b43b9be1de7a06bb8bb595e},
        abstract = {Cu-modified SO42{\^a}??/ZrO2 catalysts (XCu-SZ) with different Cu loading contents were prepared by sulfation of ZrOCl2{\^A}.8H2O with (NH4)2SO4 to form SO42{\^a}??/ZrO2 (SZ) followed by impregnation of SZ with a Cu precursor. The resulting XCu-SZ catalysts combined with a CuO{\^a}??ZnO{\^a}??ZrO2 catalyst were tested for CO2 hydrogenation to dimethyl ether (DME). The results indicated that the unmodified SZ catalyst exhibited the maximum DME yield (3.7) which was 2.0{\^a}??2.6 times higher than the DME yield of all XCu-SZ catalysts at the beginning of reaction. However, the DME yield over the unmodified SZ catalyst rapidly decreased, while that of all XCu-SZ catalysts gradually increased during the time-on-stream experiment. After 100 h, the 6 wt Cu-modified SZ catalyst achieved the maximum DME yield of 3.2 at 260 {\^A}oC and 20 bar, while the DME yield of the unmodified SZ catalyst was only 2.5. The NH3-TPD and XPS analyses indicated that more strong acid sites were present on the unmodified SZ catalyst, resulting in a coke formation and thus the rapid deactivation. For the XCu-SZ catalysts, Cu0 was formed on the surface of SZ after the reduction with H2 which accounted for the active site of hydrogenolysis of methanol to methane. During the time-on-stream experiment, Cu0 was progressively transformed to Cu2S through poisoning, leading to the continued increase of DME yield. {\^A}{\copyright} 2022 Hydrogen Energy Publications LLC},
            issn = {03603199},
        keywords = {Ammonia; Carbon dioxide; Catalyst activity; Copper oxides; Greenhouse gases; Hydrogenation; II-VI semiconductors; Zinc oxide; Zirconia, CO2 hydrogenation; CO2 utilization; Cu-modified sulphated zirconium; Dimethyl ether; Direct synthesis; Greenhouses gas; Sulfated Zirconia; Synthesis of dimethyl ethers; Time on streams; ]+ catalyst, Ethers}
}