Lignin-Based Porous Supraparticles for Carbon Capture

Abstract

Multiscale carbon supraparticles (SPs) are synthesized by soft-templating lignin nano- and microbeads bound with cellulose nanofibrils (CNFs). The interparticle connectivity and nanoscale network in the SPs are studied after oxidative thermostabilization of the lignin/CNF constructs. The carbon SPs are formed by controlled sintering during carbonization and develop high mechanical strength (58 N·mm–3) and surface area (1152 m2·g–1). Given their features, the carbon SPs offer hierarchical access to adsorption sites that are well suited for CO2 capture (77 mg CO2·g–1), while presenting a relatively low pressure drop (∼33 kPa·m–1 calculated for a packed fixed-bed column). The introduced lignin-derived SPs address the limitations associated with mass transport (diffusion of adsorbates within channels) and kinetics of systems that are otherwise based on nanoparticles. Moreover, the carbon SPs do not require doping with heteroatoms (as tested for N) for effective CO2 uptake (at 1 bar CO2 and 40 °C) and are suitable for regeneration, following multiple adsorption/desorption cycles. Overall, we demonstrate porous SP carbon systems of low cost (precursor, fabrication, and processing) and superior activity (gas sorption and capture).

Experimental and Simulation Study of the Solvent Effects on the Intrinsic Properties of Spherical Lignin Nanoparticles

“…Such a method calculates the porosity based on the freezing point depression of confined water in pores and assumes cylindrical pore geometry. , However, the SAXS intensities from the current study do not show any indication of pores with a regular size in the scale of several nanometers, due to which we hypothesize that the confined water detected by tp-DSC could in fact be present in pores with a smaller diameter than the previously reported 5.5 nm. On the other hand, Zhao et al recently reported the intrapore diameters of ∼1 nm and surface areas of 348–405 m 2 /g of the carbonized lignin supraparticles using N 2 adsorption–desorption method. The lignin supraparticles used in that work were prepared by carbonization of the assembled LNPs THF in the presence of 2.5 wt % cellulose nanofibrils.…”

Monodispersed Lignin Colloidal Spheres with Tailorable Sizes for Bio‐Photonic Materials

“…Many researchers have investigated the self-assembly process of LCSs and qualitatively demonstrated that one or two of the above intermolecular forces is the driving force during self-assembly. [21][22][23][24] Our previous work employed atomic force microscopy (AFM) force spectroscopy Lignin colloidal spheres (LCSs) are promising biomaterials for application in drug storage and delivery, pollutant adsorption, and ultraviolet protection due to their biocompatibility, amphiphilicity, and conjugated structure. However, wide size distribution of LCSs greatly limits their performances, especially in many precise and advanced applications.…”

Multi-compartment supracapsules made from nano-containers towards programmable release

“…For instance, by controlling colloidal interactions during assembly, the internal architectures of supraparticles can be varied from those of close-packed spheres 8 to the ones of Janus-like, [9][10][11][12] core-shell, [13][14][15] or mesoporous structures. 2,[16][17][18] Thanks to the existence of a vast range of synthetic nanomaterials and assembly strategies, supraparticles have shown outstanding performance in applications including catalysis, 3,19 photonics, [20][21][22] and microrobotics. [23][24][25] In spite of these advances, producing suprastructures with multiple internal compartments remains a significant challenge.…”