Experimental Study on Titanium Based Photocatalyst and its Catalytic Oxidation on Flue Gas Mercury

This paper mainly studied the effects of different iron-doped volume on photo-catalytic oxidation of TiO2 for mercury removal. Through the photocatalytic oxidation system, we evaluated the elemental mercury removal performance of TiO2 with iron-doped mass ratio of 0.5%, 1%, 2% and 3%. While the iron-doped mass ratio were 0.5%, 1%, 2% and 3%, the elemental mercury removal efficiency were 70.83%，52.89%，72.32% and 62.39% respectively, the removal efficiency increased firstly, then declined, and 2% iron-doped was the most appropriate

Download Full-text

Removal of Elemental Mercury from Flue Gas using the Magnetic Attapulgite by Mn-Cu Oxides Modification

10.21203/rs.3.rs-497732/v1 ◽

2021 ◽

Author(s):

Yifei Long ◽

Zhong He ◽

Xiaoyi Li ◽

Yajie Yin ◽

Yuan Wang ◽

...

Keyword(s):

Removal Efficiency ◽

Flue Gas ◽

Active Sites ◽

Chemical Properties ◽

Elemental Mercury ◽

Mercury Removal ◽

Impregnation Method ◽

Active Components ◽

Co Precipitation ◽

Physical And Chemical

Abstract Mercury pollution has become one of the most concerned environmental issues in the world because of its high toxicity, non-degradability and bioaccumulation. Attapulgite adsorbents modified by magnetic manganese-copper (MnxCuy-MATP) were fabricated by co-precipitation and ultrasonic impregnation method,aiming at removing Hg0 from coal-fired flue gas. BET, SEM, XRD, VSM and XPS were used to systematically explore the physical and chemical properties of the adsorbents, the effects of manganese and copper additions, reaction temperature and various components in the flue gas on the efficiency of Hg0 removal were investigated. Mn8Cu5-MATP exhibited the optimal properties, and excessive copper loadings led to the aggregation of the active components. The efficiency of mercury removal can be effectively improved by NO and HCl regardless of the absence and presence of O2, because the NO+, NO3, NO2 and Cl* produced during the reaction can promote the adsorption and oxidation of Hg0. SO2 and H2O inhibited the oxidation of Hg0 because of the competitive adsorption at the active sites, while a large amount of sulfite and sulfate were formed to block the pores. However, the introduction of copper caused the sample to obtain SO2 resistance, which resulted in a mercury removal efficiency of 84.3% even under 1500 ppm SO2. In addition, after 5 cycles of adsorption and regeneration, Mn8Cu5-MATP can still maintain excellent Hg0 removal ability. The fabricated adsorbent can save the actual production cost and effectively improve the mercury removal efficiency in sulfur-containing flue gas.

Download Full-text

The Study on the Performance of Wet Limestone-Gypsum Flue Gas Mercury Removal Additive

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.608 ◽

2013 ◽

Vol 448-453 ◽

pp. 608-612

Author(s):

Li Bao Yin ◽

Qi Sheng Xu ◽

Jiang Jun Hu ◽

Yang Heng Xiong ◽

Si Wei Chen

Keyword(s):

Removal Efficiency ◽

Flue Gas ◽

Total Mercury ◽

Elemental Mercury ◽

Flue Gas Desulfurization ◽

Mercury Removal ◽

Additive Increase ◽

Calcium Sulfite

The influences on the performance of wet flue gas desulfurization system in mercury removing after adding mercury removal additive were studied. As a consequence, the mercury removal efficiency can be improved by this kind of additive, that the efficiency of elemental mercury and total mercury is raised along with the amount of additive is increased. And so can the desulfuration efficiency. The oxidation of calcium sulfite in desulfurization is promoted by the mercury removal additive, increase the reduce speed of calcium sulfite concentration.

Download Full-text

Preparation of SiO2–TiO2 Nanocomposite and Its Application on Elemental Mercury Removal in Simulated Flue Gas

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.960-961.456 ◽

2014 ◽

Vol 960-961 ◽

pp. 456-461

Author(s):

Xue Shi ◽

Bu Ni ◽

Chao En Li ◽

Xian Li ◽

Chong Zhang ◽

...

Keyword(s):

Removal Efficiency ◽

Flue Gas ◽

Low Cost ◽

Physical Method ◽

Elemental Mercury ◽

Mercury Removal ◽

Photocatalytic Ability ◽

Absorption Of Light ◽

Nanocomposite Catalyst ◽

Direct Adsorption

SiO2–TiO2 nanocomposite was synthesized by an ultrasound-assisted pure physical method to oxidize elemental mercury (Hg0) in simulated flue gas. Due to its low cost and photocatalytic ability, SiO2 was used to dope TiO2 to modify the TiO2 photocatalyst. We put different ratio of TiO2 / SiO2 under the UV irradiation to get a low Ti/Si doping ratio and high flue gas mercury removal efficiency of SiO2–TiO2 nanocomposite catalyst. It was found that the photocatalytic activity of nanocomposite materials did not significantly improve, or even decline. This is mainly because that the presence of too much porous SiO2 may affect TiO2 on the effective absorption of light and direct adsorption of contaminants. When Ti: Si ratio was 2:1, SiO2–TiO2 nanocomposite catalyst reached its highest elemental mercury removal efficiency in the simulated flue gas.

Download Full-text

Elemental mercury removal from flue gas using heat and Co2+/Fe2+ coactivated oxone oxidation system

Chemical Engineering Journal ◽

10.1016/j.cej.2018.04.171 ◽

2018 ◽

Vol 348 ◽

pp. 464-475 ◽

Cited By ~ 52

Author(s):

Yangxian Liu ◽

Yan Wang

Keyword(s):

Flue Gas ◽

Elemental Mercury ◽

Mercury Removal ◽

Oxidation System

Download Full-text

Low-Cost Organic Adsorbents for Elemental Mercury Removal from Lignite Flue Gas

Energies ◽

10.3390/en14082174 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2174

Author(s):

Marta Marczak-Grzesik ◽

Stanisław Budzyń ◽

Barbara Tora ◽

Szymon Szufa ◽

Krzysztof Kogut ◽

...

Keyword(s):

Flue Gas ◽

Low Cost ◽

Elemental Mercury ◽

Mercury Content ◽

Flue Gases ◽

Mercury Removal ◽

Gas Purification ◽

Gas Temperature ◽

Corn Straw ◽

Flue Gas Purification

The research presented by the authors in this paper focused on understanding the behavior of mercury during coal combustion and flue gas purification operations. The goal was to determine the flue gas temperature on the mercury emissions limits for the combustion of lignites in the energy sector. The authors examined the process of sorption of mercury from flue gases using fine-grained organic materials. The main objectives of this study were to recommend a low-cost organic adsorbent such as coke dust (CD), corn straw char (CS-400), brominated corn straw char (CS-400-Br), rubber char (RC-600) or granulated rubber char (GRC-600) to efficiently substitute expensive dust-sized activated carbon. The study covered combustion of lignite from a Polish field. The experiment was conducted at temperatures reflecting conditions inside a flue gas purification installation. One of the tested sorbents—tire-derived rubber char that was obtained by pyrolysis—exhibited good potential for Hg0 into Hg2+ oxidation, resulting in enhanced mercury removal from the flue. The char characterization increased elevated bromine content (mercury oxidizing agent) in comparison to the other selected adsorbents. This paper presents the results of laboratory tests of mercury sorption from the flue gases at temperatures of 95, 125, 155 and 185 °C. The average mercury content in Polish lignite was 465 μg·kg−1. The concentration of mercury in flue gases emitted into the atmosphere was 17.8 µg·m−3. The study analyzed five low-cost sorbents with the average achieved efficiency of mercury removal from 18.3% to 96.1% for lignite combustion depending on the flue gas temperature.

Download Full-text

Core-shell nanostructure α-Fe2O3/SnO2 binary oxides for the catalytic oxidation and adsorption of elemental mercury from flue gas

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2021.105137 ◽

2021 ◽

Vol 9 (2) ◽

pp. 105137

Author(s):

Yongpeng Ma ◽

Tengfei Xu ◽

Ling Li ◽

Jiandong Wang ◽

Yu Li ◽

...

Keyword(s):

Catalytic Oxidation ◽

Flue Gas ◽

Elemental Mercury ◽

Core Shell ◽

Binary Oxides

Download Full-text

Photocatalytic Oxidation of Shenfu Bituminous Coal and Xilinhaote Lignite with H2O2 over TiO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.1684 ◽

2011 ◽

Vol 233-235 ◽

pp. 1684-1689 ◽

Cited By ~ 1

Author(s):

Heng Shen Xie ◽

Zhi Min Zong ◽

Qing Wei ◽

Pei Zhi Zhao ◽

Jian Jun Zhao ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Titanium Dioxide ◽

Catalytic Oxidation ◽

Photocatalytic Oxidation ◽

Bituminous Coal ◽

Straight Chain ◽

Photo Catalytic Oxidation ◽

Alkyl Side Chains ◽

Lignite Coal ◽

Oxidation Effect

Shenfu bituminous coal (SFBC) and Xilinhaote lignite (XL) were subject to photo-catalytic oxidation with hydrogen peroxide over titanium dioxide. The reaction mixtures were extracted with acetone exhaustively. The extracts were analyzed with FTIR and GC/MS. The results show that coals be oxidized selectively and degraded partially. Compared with the bituminite coal, the oxidation effect of the lignite coal with active hydrogens is more obvious. The alkyl side chains of the macromolecules, particularly, chains of methyl, methylene and aromatic, are the most vulnerable in relation to other compounds in coals. Moreover, the increasing of straight-chain alkanes and the decreasing of condensed nucleus in SFBC and XL through oxidation suggest that the oxidation is an effective method of coal utilization with no difficultly, also be friendly towards the environment after treated as well as in the process of the treatment.

Download Full-text