Efficient CO₂ Capture by Nitrogen-Doped Biocarbons Derived from Rotten Strawberries

Abstract

In this study, rotten strawberries were used as carbon precursor to prepare nitrogen-doped porous biocarbons for CO 2 capture. The sorbents were synthesized by hydrothermal treatment of rotten strawberries, followed by KOH activation. The nitrogen in the resulting sorbents is inherited from the rotten strawberry precursor. This series of samples demonstrates high CO 2 uptake at 1 bar, up to 4.49 mmol g −1 at 25 °C and 6.35 mmol g −1 at 0 °C. In addition to narrow micropore volume and nitrogen content, the pore size of narrow micropores also plays a key role in determining the CO 2 capture capacity under ambient conditions. Furthermore, these sorbents possess stable reusability, moderate heat of CO 2 adsorption, quick CO 2 adsorption kinetics, reasonable CO 2 /N 2 selectivity, and high dynamic CO 2 capture capacity under simulated flue gas conditions. All these merits along with the zero-cost and wide availability of rotten strawberry precursor make this type of sorbent highly promising in CO 2 capture from combustion flue gas.

Novel Nitrogen-Doped Porous Carbons Derived from Graphene for Effective CO2 Capture

“…With the continuous increase of atmospheric CO 2 concentrations, there is an imperative need for inexpensive and effective removal of CO 2 from flue gas. , Among various CO 2 capture technologies, CO 2 adsorption by solid adsorbents is a promising approach because of its merits of low capital investment, low energy consumption, ease of operation, and lack of equipment corrosion. − The goal of this technique is to obtain solid adsorbents with excellent performance including (1) high CO 2 adsorption capacity, (2) high selectivity of CO 2 over N 2 , (3) rapid CO 2 adsorption/desorption kinetics, (4) moderate heat of enthalpy, and (5) excellent thermal, chemical, and mechanical stability. Of different sorbents explored for CO 2 adsorption such as zeolites, metal oxides, metal–organic frameworks (MOFs), porous polymers, , and ionic liquids, − carbonaceous materials are receiving increased interest because of their merits such as minimal cost, high surface area, tunable pore structure, hydrophobic property, inertness to chemicals, thermal and mechanical stability, and their environmentally benign nature. − To date, various porous carbons synthesized from different methods, i.e., physical or chemical activation using different precursors such as coal, petroleum coke, − and biomass materials, − have been widely researched for CO 2 capture. It has been revealed that the narrow micropore (<1 nm) of the carbonaceous materials determines their CO 2 adsorption capacities at ambient conditions. ,, Furthermore, integration of the N element into the carbon skeleton can obviously change the electronic distribution of the carbon surface, which in turn increase the surface polarity of the carbon materials.…”

One‐pot synthesis of high N‐doped porous carbons derived from a N‐rich oil palm biomass residue in low temperature for CO 2 capture

“…There are usually two ways to dope nitrogen into the carbon framework. 21 The first is to treat the carbon precursor with a nitrogen source, and the second is to pyrolyze the nitrogen-carbon precursor. Both methods have advantages and disadvantages, but low nitrogen content is a common feature.…”

“…There are usually two ways to dope nitrogen into the carbon framework . The first is to treat the carbon precursor with a nitrogen source, and the second is to pyrolyze the nitrogen‐carbon precursor.…”

Foaming Effect of a Polymer Precursor with a Low N Content on Fabrication of N-Doped Porous Carbons for CO2 Capture

“…Among the solid adsorbents, N-doped porous carbons (NDPCs) with large surface areas, excellent microporosities, and high chemical/thermal stabilities have been considered to be an attractive and promising candidate for reducing the excessive level of emissions of CO 2 . − Carbonizing N-containing polymers for the fabrication of NDPCs is universal because the N species incorporated into polymer precursors will play a crucial role in the foaming agent during the carbonization process at proper temperatures and thus effectively enhance the surface areas and porosities of the generated NDPCs. ,, However, the polymer precursors employed for the preparation of NDPCs have to involve relatively high N contents to make the foaming agent roles effective, and the NDPCs obtained usually perform unsatisfactorily in terms of both their porosities and CO 2 adsorption performance. For instance, Liu et al prepared the NDPC labeled as UFCA-2-600 from the polymer precursor UFC with a high N content of 23.7 wt %; however, the BET surface areas ( S BET ) were just 1055 m 2 /g, and the CO 2 capacity was only 3.2 mmol/g (at 25 °C and 1 bar) .…”