The effects of metal oxide blended activated coke on flue gas desulphurization

Abstract

The objective of this study was to investigate the possibility of using some natural minerals or industrial waste containing some metal oxides to prepare modified activated coke (M/AC) for flue gas desulphurization. The metal oxides, i.e. Fe 2 O 3 , Co 2 O 3 , CuO and Ni 2 O 3 , were used as additives to prepare M/AC by a blending method. The results show that the M/AC could effectively improve desulphurization performance, and the highest sulphur capacity was obtained at 143 mg g À1 for the Ni/AC sample with a blending ratio of 12 wt%, which was higher than that of the blank sample (97 mg g À1 ). The addition of metal oxides by the blending method could affect the textural properties of M/AC evidently and the influence was different with different metal oxides and blending ratios. On the other hand, M/AC samples have higher contents of oxygen-containing functional groups, with the highest for the Ni/AC sample, and have higher contents of p-p* transition groups, compared with blank activated coke. The metal oxides loaded on the M/AC were mainly transformed to metallic particles during the activation process, and to metal sulfate and partially metal oxides after the desulphurization process. † Electronic supplementary information (ESI) available: Fig. S1 shows the breakthrough curves of the metal oxides for ue gas desulphurization. Fig. S2 shows the overall XPS spectrum of prepared activated coke. Fig. S3 shows the binding energy patterns of C 1s for prepared activated cokes. See

Removal of SO2 from Flue Gas on a Copper-Modified Activated Coke Prepared by a Novel One-Step Carbonization Activation Blending Method

“…In our previous work, copper-modified AC was prepared by a two-step carbonization-activation blending method, in which the carbonization process (600 °C for 1 h) was carried out, and then the carbonized char mixed with metals was activated (950 °C for 1 h). 16 It was found that, compared to the AC, the sulfur capacity of Cu/AC increased by 41.2%. 16 However, for the two-step carbonization-activation blending method, twice heating (carbonization and activation processes) was needed, and a long time was required due to the cooling procedure after carbonization.…”

“…15 Yang and coworkers found that the introduction of copper species can increase the surface basic sites of Cu/AC, which was favorable for the SO 2 adsorption. 16 Zhao et al reported that the pore width of CuO/AC increased upon CuO addition, which benefited to the adsorption of pollutants from flue gas. 17 Yuan et al pointed out that copper-ore-modified AC facilitated the formation of oxygen-containing functional groups on the ACcopper-ore surface, contributing greatly to the high sulfur capacity.…”

“…18 Meanwhile, for Cu/AC obtained using the blending method, the BET specific surface area and micropore volume reduced only 7.3% and 3.1%, respectively. 16 The blending method was also in favor of achieving uniform distribution of additives throughout the carbon matrix due to the reaction occurring between the metal oxides and the carbon substrate during the activation. 20 The uniform incorporation of copper species into modified AC is difficult and can reduce the surface area and porosity of AC.…”

The study on continuous denitrification, desulfurization of pyrolusite/activated coke hybrid catalyst

“…15 Among these technologies, surface modication by loading transition metals attracted great attention. 6,16 Natural minerals, rich in transition metals, showed great prospect due to its relatively low cost and the simple preparation procedure when it used as precursor, 17 and the catalytic activity and stability of some kinds of natural minerals for SO 2 and NO removal also have been proved. 18,19 However, it is noteworthy that the formation of metal sulphates during the desulfurization process on the surface of modied AC is unavoidable for almost all the transition metals, and they are difficult to be decomposed under commonly used regeneration temperatures (#500 C).…”

Suitability of pyrolusite as additive to activated coke for low‐temperature NO removal

“…15,18,19 The transition metals with catalytic activity were typically supported on AC by solution deposition and/or solid blending methods. In recent years, the solid blending method was widely researched, 20 especially low cost natural minerals as catalyst or surface modifier, 21,22 because only soluble metal salts can be used as catalyst. In addition, the preparation of modified AC by the blending method could be completed in one-step carbonization and activation.…”