Polyacrylonitrile Nanoparticle‐Derived Hierarchical Structure for CO₂ Capture

Abstract

The production of porous clusters by controlled aggregation of polyacrylonitrile nanoparticles and thermal treatment, and their application to CO2 capture are reported. The synthesis of the primary particles by emulsion polymerization exhibits good reproducibility and is easy to scale up. The subsequent gelation of the produced latexes (controlled destabilization by salt addition) results in the formation of macroporous monoliths of nanoparticles with a mean pore diameter of 100 nm. A carefully assessed thermal treatment is applied to the dried monolith after grinding. The produced porous clusters are processed with three high‐temperature steps: oxidation, stabilization, and pyrolysis. The latter allows for the creation of micropores in the initially non‐porous nanoparticles, thus enabling access to the remaining nitrogen‐bearing species present in the pyrolyzed polymer. The relative contributions of the remaining nitrogen‐bearing species and of the micropores are elucidated by applying different oxidation temperatures. In particular, the fraction of the pores with diameter smaller than 0.7 nm is decisive in determining the final capture ability. After a treatment including oxidation at 240 °C, stabilization at 350 °C, and pyrolysis at 900 °C, the best reported material shows an average CO2 adsorption capacity of 3.56±0.17 mol (CO2) kg−1 at 0 °C and 1 atm.

Nanobiotechnology: advances in the use of nanomaterials to increase CO2 biofixation by microalgae

“…In the environmental area, studies aimed to remove water and air contaminants by application of nanoparticles (Khan et al 2019). Furthermore, PAN polymeric nano bers, containing NPsFe 2 O 3 , can be used to adsorption of greenhouse gases such as CO 2 (Beltzung et al 2018;Vaz et al 2019).…”

“…In addition, the interactions between contaminants, such as CO 2 and nanoparticles are dependent on other characteristics of nanomaterials as composition, size, morphology, porosity, and polydispersity (Khan et al 2019). These characteristics are dependent on the polymer chosen, as well as the technique applied for the development of nanomaterials (Beltzung et al 2018;Khan et al 2019).…”

“…This technology can be associated with microalgal cultivation with a 57% increase in the rate of CO 2 bio xation, compared to assay without nano bers. Polymeric nanoparticles also stand out as potential CO 2 adsorbents (Beltzung et al 2018), and studies on the performance of these nanomaterials associated with the biological process are innovative. Moreover, compared to the usual metallic nanoparticles, polymeric nanoparticles do not appear to have cytotoxic effects on microalgae, when exposed in the long term (Jeevanandam et al 2018).…”

Incorporation and distribution of noble metal atoms in polyacrylonitrile colloidal particles using different polymerization strategies

“…In addition, all the synthesis involving AN required the use of an additional surfactant (KPE) to ensure good stability and prevent spontaneous aggregation of the nanoparticles inside the reactor. 49…”

Effect of heat treatment temperature on CO2 capture of nitrogen‐enriched porous carbon fibers

“…As vast precursors that can be used for the preparation of carbon materials, nitrogen‐containing polymers can be chosen to prepare carbons enriched with nitrogen. These starting materials could be polyacrylonitrile (PAN), polypyrrole, polyurethane, polydopamine, melamine, as well as their combinations . Among these nitrogen‐containing polymers, PAN is spinnable and carbon fibers can be obtained by thermal treatment.…”