Acquiring an Efficient Warm‐CO₂ Sorbent from Advanced Pyrolysis of Magnesium Oxalate

Abstract

For the first time, porous MgO with a Brunauer–Emmett–Teller (BET) surface area over 200 m2 g−1 can be simply obtained from pyrolysis of common magnesium oxalate without any solvent or additive. The obtained porous MgO had a large surface area of 278.5 m2 g−1 and captured 30.8 mg g−1 of CO2 in the instantaneous adsorption at 473 K, comparable with many MgO‐based sorbents prepared through complex procedures. Use of a U‐pipe furnace along with the specific “throughout” sweeping mode of nitrogen carrier gas enable this efficient warm‐CO2 sorbent to be fabricated in a simple way. Factors including contacting modes between precursor salt and flowing gas, flow rate, type of gas and salt were carefully studied, and related to the pore structure and adsorption character of the MgO samples. Apart from the capability of trapping CO2 mixed with SO2 and NO at 473 K, the MgO sample showed a high ratio of exposed strong basic sites (70.5 %), which provides a useful solid strong base for control of CO2 in flue gas.

Nanostructured MgO Sorbents Derived from Organometallic Magnesium Precursors for Post-combustion CO2 Capture

“…CO 2 capture capacities of these sorbents were in the range of 0.39−1.82 mmol of CO 2 /g, depending upon the different testing conditions. 22,32,35,45,47 Organic magnesium precursors of Mg(Ac) 22,28,32,35,47 The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.energyfuels.8b00866.…”

“…In contrast, the solid-state reaction process could be a facile, economic, and green route for sorbent development. 28,32 Therefore, the direct pyrolysis or calcination of magnesium precursors should be promising for facile preparation of MgO sorbents. The major concern for this method is to determine suitable magnesium precursors.…”

“…Previous work indicated that MgO presented a high theoretical CO 2 capture capacity, while the CO 2 uptake of commercial bulk MgO could be as low as 0.5 mmol of CO 2 /g as a result of the limited base sites. , Besides, the carbonation process of MgO was kinetically controlled, and the reaction rate could be limited by its high lattice energy. , Thus, the principal problem for MgO sorbents is the limited CO 2 uptake and reaction rate. To improve their CO 2 capture performances, attempts, such as optimizing the synthesis methods and fabricating nanosized sorbents doped with alkaline metal eutectic mixtures, have been made to enhance their textural and surface properties and to reduce the activation energy. − One important approach to achieving such goals is to prepare porous MgO sorbents using different magnesium precursors. Precipitation, hydrothermal, and sol–gel methods have been widely adopted to fabricate highly efficient CO 2 sorbents with improved textural properties and controlled surface morphologies. ,,, However, these synthesis routes will consume massive costly raw materials and chemical additives.…”

“…Precipitation, hydrothermal, and sol–gel methods have been widely adopted to fabricate highly efficient CO 2 sorbents with improved textural properties and controlled surface morphologies. ,,, However, these synthesis routes will consume massive costly raw materials and chemical additives. In contrast, the solid-state reaction process could be a facile, economic, and green route for sorbent development. , Therefore, the direct pyrolysis or calcination of magnesium precursors should be promising for facile preparation of MgO sorbents. The major concern for this method is to determine suitable magnesium precursors.…”

Effects of ZnCl2 on the distribution of aldehydes and ketones in bio-oils from catalytic pyrolysis of different biomass

“…In contrast, biomass is a promising alternative to fossil fuel because of its renewable and carbon-neutral nature. Biomass can be used as a feedstock to produce various environmentally friendly materials, such as bio-asphalt (Zelelew et al 2013), hydrophobic agents (Penmetsa and Steele 2012), and adsorbents (Li et al 2017). Many preceding studies have focused on biooil through the incorporation of biomass pyrolysis technology (Wang et al 2015).…”