Effects of Preparation Conditions on the Performance of Simultaneous Desulfurization and Denitrification over Ni/Fe Hydrotalcite-like Compounds

详细信息    查看全文

• 作者：Xiao Liu ; Honghong Yi ; Xiaolong Tang ; Yuantao Li ; Baocong Cui ; Yaen Wang
• 刊名：Energy & Fuels
• 出版年：2016
• 出版时间：March 17, 2016
• 年：2016
• 卷：30
• 期：3
• 页码：2295-2301
• 全文大小：434K
• ISSN：1520-5029

文摘

The effects of a series divalent metals, ratios of metals, and calcination temperature on the performance of simultaneous desulfurization and denitrification over the hydrotalcite-like compound (HTLC) catalyst were investigated, and the removal mechanism of HTLCs was characterized by X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) surface areas, temperature-programmed desorption–mass spectroscopy (TPD–MS), and Fourier transform infrared spectroscopy (FTIR) analyses. The results showed that Ni/Fe HTLCs had the best adsorption property to remove SO₂ and NO among the three HTLCs: Ni/Fe, Mg/Fe, and Co/Fe HTLCs. The optimum preparation conditions of the adsorbent were at the Ni/Fe mole ratio of 2 and calcined at 300 °C. The high specific surface area as well as the existence of Fe₂O₃ phases resulted in excellent NO and SO₂ adsorption capacities. The removal rate of SO₂ and NO still remained at 95 and 50% when the reaction time had extended to 40 min. A total of 13% CO₂ of the simulated flue gas had no significant effect on the adsorption of NO and SO₂. The NO adsorption capacity decreased slowly with the increase of the H₂O concentration, and a total of 2% H₂O enhanced the SO₂ adsorption capacity but inhibited the SO₂ adsorption slightly when the H₂O concentration still increased to 5%. SO₂ was chemisorbed on the Ni/Fe HTLCs, and the products were sulfate and sulfite according to the characterization results. However, NO was physisorbed and chemisorbed on the Ni/Fe HTLCs, and the chemisorption products were nitrate and nitrite.