CO2 capture in humid gas using ZnO/activated carbon and ZnO reactivity with CO2

Abstract

Carbon dioxide capture with ZnO/activated carbon adsorbates and reactivity of ZnO particle with CO 2 are discussed for the effective CO 2 capture in humid exhaust gas. Coarse ZnO particles (d = 670 nm), and small diameters, d \ 20 nm, of zinc oxide particles on activated carbon supports were prepared. The amounts of CO 2 adsorbed on ZnO particles and activated carbon supports were measured and calculated. The calculated value and thermal gravimetric analysis results indicate that only the surface layer (\0.5 nm) of ZnO particles reacts with CO 2 and H 2 O for all sizes of ZnO particles. These results lead to the conclusion that ZnO reactivity with CO 2 is still independent of the particle size even in the small diameters in this study. The results quantitatively present the gas-phase carbonation rate of ZnO and its independency on the particle diameter for the first time. This research sheds light on the difficulty in using ZnO as CO 2 adsorbent. Some possible solutions for the difficulty are also discussed in view of enhancing of its reactivity.

Membrane Absorption Coupling Process for CO2 Capture: Application of Water-Based ZnO, TiO2, and Multi-Walled Carbon Nanotube Nanofluids

“… Taira et al implemented ZnO for CO 2 adsorption from humid gases. According to their results, CO 2 chemisorption takes place on ZnO particles, and after an adsorption test, the carbonate species formed on the surface of ZnO particles still remained after being purged by N 2 gas . Kansha et al introduced a process for CO 2 chemical absorption by ZnO solids in a fluidized bed.…”

“…According to their results, CO 2 chemisorption takes place on ZnO particles, and after an adsorption test, the carbonate species formed on the surface of ZnO particles still remained after being purged by N 2 gas. 53 Energy & Fuels surfaces by mixed O and Zn atoms and physisorb on singly terminated surfaces. 58 Many studies 26,27 have reported TiO 2 nanofluid as the best CO 2 nano-absorbent among CuO, MgO, SiO 2 , and Al 2 O 3 .…”

Identification of Nano-Metal Oxides That Can Be Synthesized by Precipitation-Calcination Method Reacting Their Chloride Solutions with NaOH Solution and Their Application for Carbon Dioxide Capture from Air—A Thermodynamic Analysis

“…The above is confirmed for M(x) = Fe(II), Zn(II), La(III), Ce (III) and Sn(II) under 150 bar in [ 92 , 93 , 94 , 95 , 96 ]. Further, CaO [ 71 , 97 , 98 , 99 , 100 ], BeO [ 64 ], Co 3 O 4 [ 101 ], MgO [ 102 , 103 ], FeO, Fe 2 O 3 , Fe 3 O 4 [ 104 ], Li 2 O [ 66 , 105 ], CuO [ 106 , 107 ] and NiO [ 108 ] were used as sorbents in a CO 2 environment. ZnO has been also studied for CO 2 capturing in CO 2 environment using the pressure at 1–25 bar [ 109 , 110 , 111 , 112 ].…”