Comprehensive parametric assessment of steam-adsorption intensified hydrogenation of CO2 to DME
International Journal of Hydrogen Energy, cilt.172, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 172
- Basım Tarihi: 2025
- Doi Numarası: 10.1016/j.ijhydene.2025.151320
- Dergi Adı: International Journal of Hydrogen Energy
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Chemical Abstracts Core, Chimica, Compendex, Environment Index, INSPEC
- Anahtar Kelimeler: Carbon dioxide, Dimethyl ether, Hydrogenation, Intensification, Sorption enhancement
- Boğaziçi Üniversitesi Adresli: Evet
Özet
Direct CO2-to-DME conversion on CuO-ZnO-Al2O3 (CZA) and PTA (phosphotungstic acid)/γ-Al2O3 catalyst mixture is intensified by integrated H2O capture via Zeolite 3A (Z3A) adsorbent. The adsorbent-free experiments involving comparison of the PTA/γ-Al2O3 and γ-Al2O3 catalysts at 215–265 °C, 3 MPa, gas hourly space velocity (GHSV) = 1750 h−1 and H2:CO2:N2 = 3:1:1 show that PTA integration allows > tenfold increase in the specific DME production rate which is maximized at 245 °C and CZA:PTA/γ-Al2O3 mass ratio of 1:1. At these conditions, pressure swing adsorption assisted testing at all GHSV (5250, 7000, 10500 h−1)/Z3A loading (2, 6, 10 g) combinations shows the clear trade-off between catalytic activity and productivity. CO2 conversion and DME selectivity are maximized at 5250 h−1/10 g Z3A due to increased contact time and H2O uptake capacity. However, peak productivity is observed at 7000 h−1/6 g Z3A because of shortened adsorbent regeneration. The role of acidity in the presence of sorption enhancement is highlighted by the ∼75 % and ∼19 % increases in DME selectivity and productivity, respectively, when the PTA/γ-Al2O3 catalyst is used instead of γ-Al2O3. The stability of the CZA + PTA/γ-Al2O3 + Z3A system in driving intensified CO2 valorization to DME is demonstrated by the nearly identical reaction-regeneration cycles over 50 h.