کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10244381 | 47681 | 2005 | 16 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Novel Fe-Mn-Zn-Ti-O mixed-metal oxides for the low-temperature removal of H2S from gas streams in the presence of H2, CO2, and H2O
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
کاتالیزور
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
The efficiency of Fe-Mn-Zn-Ti-O mixed-metal oxides of varying composition prepared by sol-gel methods toward removal of H2S from a gas mixture containing 0.06 vol% H2S, 25 vol% H2, 7.5 vol% CO2, and 1-3 vol% H2O was studied in the 25-100â°C range. In particular, the effects of the Fe/Mn molar ratio in the Fe-Mn-Zn-Ti-O solids on the H2S uptake and regeneration performance of the solids were studied. The nominal chemical composition (metal mol%) of the Fe-Mn-Zn-Ti-O solids was found to strongly influence the chemical composition, particle size, and morphology of the crystal phases formed. It was found that the 5 Fe-15 Mn-40 Zn-40 Ti-O mixed-metal oxide provides the highest H2S uptake as fresh and after regeneration in 20% O2/He gas mixture in the 500-750â°C range compared with the other solids investigated. It was also found that 5 Fe-15 Mn-40 Zn-40 Ti-O exhibits higher H2S uptake than a commercial Ni-based H2S adsorbent in the 25-50â°C range. In particular, a three times greater H2S uptake at 25â°C compared with that on the commercial adsorbent was found. The effectiveness of the regeneration procedure of 5 Fe-15 Mn-40 Zn-40 Ti-O solid after complete sulfidation was found to be in the 48-82% range, depending on the sulfidation temperature and regeneration conditions applied. A detailed characterization of the fresh, sulfided, and regenerated 5 Fe-15 Mn-40 Zn-40 Ti-O and 20 Fe- 40 Zn-40 Ti-O solids, which exhibited the best and worst H2S uptake performance, respectively, using BET, XRD, Raman, XPS, and Mössbauer techniques revealed important information on the sulfidation mechanism. The present work provides new fundamental knowledge that could trigger further research efforts toward the development of alternative mixed metal oxides not based on toxic chromia (Cr2O3-Fe2O3/α-Al2O3), which is used today in several industrial plants for the catalytic oxidation of H2S (Claus process).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 236, Issue 2, 10 December 2005, Pages 205-220
Journal: Journal of Catalysis - Volume 236, Issue 2, 10 December 2005, Pages 205-220
نویسندگان
K. Polychronopoulou, F. Cabello Galisteo, M. López Granados, J.L.G. Fierro, T. Bakas, A.M. Efstathiou,