Uniform dispersion of cobalt nanoparticles over nonporous TiO2 with low activation energy for magnesium sulfate recovery in a novel magnesia-based desulfurization process

Wang, Lidong; Qi, Tieyue; Wang, Juan; Zhang, Shihan; Xiao, Huining; Ma, Yanhui

doi:10.1016/j.jhazmat.2017.08.080

Cited by 57 publications

(26 citation statements)

References 44 publications

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“…The activity of the as‐prepared Co‐CS/AS catalyst is compared with previously reported catalyst, and the results are presented in Table . The Co‐CS/AS catalyst exhibits a comparable activity with Co/molecular sieve , Co/carbon nanotube , Co/SBA‐15 , and Co/TiO 2 catalysts, while it has the great advantage to reduce the catalyst cost by lowering the optimal cobalt loading.…”

Section: Resultsmentioning

confidence: 99%

“…The pathway of sulfite oxidation catalyzed by cobalt‐based CS/CA was proposed as

{SO}_{3}^{2 -} + C o_{2} {normalO}_{3} \to {SO}_{4}^{2 -} + 2 CoO

{SO}_{3}^{2 -} + 2 C o O \to {SO}_{4}^{2 -} + C o_{2} O

C o_{2} O + \frac{1}{2} O_{2} \to 2 C o O

2 C o O + \frac{1}{2} O_{2} \to C o_{2} O_{3}

…”

Section: Discussionmentioning

confidence: 99%

“…Small and medium‐sized industrial boilers commonly employ magnesium desulfurization for flue gas desulfurization . This process requires an extremely small space, in addition to exhibiting high efficiency and low energy consumption . However, the relatively slow oxidation of sulfite by‐products may engender high by‐product recycling costs and energy consumption.…”

Section: Introductionmentioning

confidence: 99%

“…Moreover, the unreacted sulfite involved in the effluent will deplete the dissolved oxygen, resulting in serious secondary pollution. Using a catalyst to increase the rate of magnesium sulfite oxidation can effectively solve the preceding problems , which might benefit for downsizing the absorber as well.…”

Section: Introductionmentioning

confidence: 99%

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Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Wang

Zhang

et al. 2018

Env Prog and Sustain Energy

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Oxidation of magnesium sulfite is a key step in the wet magnesia desulfurization. Using the mixture of waste corn stalk (CS) and activated sludge (AS) as a support, the cobalt‐based catalyst was prepared by the impregnation method to promote the oxidation rate. The results indicated that the catalysis performance is highly dependent on the ratio of CS/AS in which 8:2 is the optimal, and that with the cobalt loading of 0.6% dominates the catalytic activity. The physicochemical properties of catalyst were identified by FTIR, XRD, TEM and XPS to reveal the catalytic mechanism. The catalyzed oxidation kinetics of magnesium sulfite was investigated in a bubbling tank. The reaction orders with respect to catalyst, magnesium sulfite and oxygen were achieved to be 0.75, 0 and 0.67, respectively. The apparent activation energy were derived as 34.9 kJ·mol−1. Integrating with a three‐phase reaction model, it was inferred that the overall oxidation is controlled by the inner diffusion of oxygen. The research results can serve as a reference for the development of low‐cost catalytic techniques for the magnesia desulfurization. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 201–207, 2019

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Section: Resultsmentioning

confidence: 99%

“…The pathway of sulfite oxidation catalyzed by cobalt‐based CS/CA was proposed as

{SO}_{3}^{2 -} + C o_{2} {normalO}_{3} \to {SO}_{4}^{2 -} + 2 CoO

{SO}_{3}^{2 -} + 2 C o O \to {SO}_{4}^{2 -} + C o_{2} O

C o_{2} O + \frac{1}{2} O_{2} \to 2 C o O

2 C o O + \frac{1}{2} O_{2} \to C o_{2} O_{3}

…”

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Wang

Zhang

et al. 2018

Env Prog and Sustain Energy

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“…However, the tendency declines slightly after Co loading reaches 50 wt. %, which might be due to the fact that the excessive Co species has agglomerated on the surface of support [13,14,16,45,46]. Moreover, the catalysis performance of cobalt-based catalysts for sulfite oxidation, including Co-MS, Co-CNTs, Co-SBA-15, and Co-TiO 2 , are thoroughly compared in Figure S3, in which the active cobalt species are loaded onto the different supports.…”

Section: Catalytic Performance Measurementmentioning

confidence: 99%

Simultaneous Catalysis of Sulfite Oxidation and Uptake of Heavy Metals by Bifunctional Activated Carbon Fiber in Magnesia Desulfurization

Wang

et al. 2020

Catalysts

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Sulfite and heavy metals are crucial pollutants in the slurry produced by flue gas desulfurization. In this study, a novel cobalt-based activated carbon fiber (Co-ACFs) catalyst-adsorbent was synthesized using an impregnation method; this bifunctional catalyst-adsorbent was used in wet magnesia desulfurization for the simultaneous catalytic oxidation of magnesium sulfite and uptake of heavy metal (Hg 2+ , Cd 2+ , and Ni 2+ ) ions. The morphology and surface chemistry of ACFs before and after cobalt loading were investigated using various characterization methods. The kinetics on catalytic oxidation of magnesium sulfite was investigated, and the effects of operation conditions on the simultaneous adsorption capacity of heavy metals were examined. Relative to a non-catalysis material, the 40% Co-ACFs material increased the oxidation rate of magnesium sulfite by more than five times. The Langmuir model can describe the adsorption behavior of Co-ACFs on Hg 2+ , Cd 2+ , and Ni 2+ , indicating that the simultaneous uptake of heavy metals is a single-layer adsorption process. The maximum adsorption capacities for Hg 2+ , Cd 2+ , and Ni 2+ are 333.3, 500, and 52.6 mg/g, respectively. A pseudo-second-order model confirmed that the removal of heavy metals is controlled by the chemisorption process.Catalysts 2020, 10, 244 2 of 18 oxidation rate of magnesium sulfite, the oxidation is difficult to accomplish in a real desulfurization process. This problem has become the paramount bottleneck of the oxidation enrichment technology. The excessive sulfite might exhaust the dissolved oxygen in the effluent and decomposed into SO 2 , resulting in further environmental risks. Meanwhile, a large number of heavy metal particles are collected in the desulfurization slurry, which can migrate and transform during the desulfurization process. For example, Hg 2+ present in the desulfurized slurry is easily released into the atmospheric environment because the ion is reduced to Hg 0 by sulfite [9][10][11]. Some co-existing Cd 2+ ions may co-crystallize with the saturated magnesium sulfate in the recovered products to cause secondary pollution. Therefore, the simultaneous removal of heavy metals from desulfurized slurries becomes another technical problem for magnesium sulfate recovery.Studies have shown that transition metal ions such as Co 2+ , Mn 2+ , Fe 2+ , and Cu 2+ can be used for improving the oxidation rate of sulfite. Among these ions, Co 2+ exhibits the highest performance in terms of sulfite oxidation [12]. However, separating the homogeneous catalyst from the desulfurization slurry is difficult and the material must be supplemented continuously, thus resulting in a high operation cost and secondary pollution due to the use of magnesium sulfate products. To address this problem, our research group developed a series of cobalt-based heterogeneous catalysts [13-18] by using impregnation, coprecipitation, and hydrothermal synthesis. These catalysts effectively solved the catalyst separation problem. However, a magnesium desulfurizat...

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Cu Decorated Rh/TiO₂ Catalyst for Selective Hydrogenation of Phenylacetylene to Styrene

Liu

Zhao

et al. 2021

ChemNanoMat

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Phenylacetylene as an impurity in styrene is poisonous to catalysts for styrene polymerization in the production of polystyrene plastics. The selective hydrogenation of phenylacetylene to styrene is an industrially promising route to overcome this challenge yet lacks cost‐effective catalysts to prevent the overhydrogenation of styrene to ethylbenzene. In this work, we report an efficient and robust copper‐decorated Rh/TiO2 catalyst for the selective hydrogenation of phenylacetylene to styrene. By optimizing the copper coverage on TiO2 supported Rh nanoparticles, we achieved a selectivity of 83% towards styrene formation at a phenylacetylene conversion of 93%. The appropriate Cu coverage is found to modulate the electronic states of surface Rh atoms and changes the Rh exposed active sites, weakening the binding strength of alkene and hydrogen intermediates on Rh and thus mitigating the overhydrogenation and enhancing the selectivity for styrene generation. This work offers insights on the rational design of efficient Rh‐based bimetallic catalysts for selective hydrogenation of phenylacetylene to styrene.

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Uniform dispersion of cobalt nanoparticles over nonporous TiO2 with low activation energy for magnesium sulfate recovery in a novel magnesia-based desulfurization process

Cited by 57 publications

References 44 publications

Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Simultaneous Catalysis of Sulfite Oxidation and Uptake of Heavy Metals by Bifunctional Activated Carbon Fiber in Magnesia Desulfurization

Cu Decorated Rh/TiO₂ Catalyst for Selective Hydrogenation of Phenylacetylene to Styrene

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Uniform dispersion of cobalt nanoparticles over nonporous TiO2 with low activation energy for magnesium sulfate recovery in a novel magnesia-based desulfurization process

Cited by 57 publications

References 44 publications

Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Kinetics of magnesium sulfite oxidation catalyzed by cobalt using a straw/sludge substrate as support

Simultaneous Catalysis of Sulfite Oxidation and Uptake of Heavy Metals by Bifunctional Activated Carbon Fiber in Magnesia Desulfurization

Cu Decorated Rh/TiO2 Catalyst for Selective Hydrogenation of Phenylacetylene to Styrene

Contact Info

Product

Resources

About

Cu Decorated Rh/TiO₂ Catalyst for Selective Hydrogenation of Phenylacetylene to Styrene