Milling as a route to porous graphitic carbons from biomass

Abstract

This paper reports a simple way to produce porous graphitic carbons from a wide range of lignocellulosic biomass sources, including nut shells, softwood sawdust, seed husks and bamboo. Biomass precursors are milled and sieved to produce fine powders and are then converted to porous graphitic carbons by iron-catalysed graphitization. Graphitizing the raw (unmilled) biomass creates carbons that are diverse in their porosity and adsorption properties. This is due to the inability of the iron catalyst precursor to penetrate the structure of dense biomass material. Milling enables much more efficient impregnation of the biomass and produces carbons with homogeneous properties. Lignocellulosic biomass (particularly waste biomass) is an attractive precursor to technologically important porous graphitic carbons as it is abundant and renewable. This simple method for preparing the biomass enables a wide range of biomass sources to be used to produce carbons with homogeneous properties. This article is part of the theme issue ‘Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)’.

Iron-catalyzed graphitization for the synthesis of nanostructured graphitic carbons

“…61–63 However, the high cost of these specialist carbon materials limits their range of applications, particularly in environmental remediation. 64 Iron-catalyzed graphitization may offer an economical and sustainable solution, given the potential to transform bio-derived materials 65 or even waste biomass 66 into complex carbons with promising adsorption properties.…”

Catalytic Graphitization by Nickel Nitrate and Characterization on Palm Oil Solid Waste Graphite

“…Nickel nitrate have been utilized to synthesize graphitic carbon compounds from a variety of organic precursors, including raw biomass like palm oil solid waste. The organic precursor decomposes to amorphous carbon during pyrolysis, whereas the nickel precursor creates Ni nanoparticles to catalyze the conversion of amorphous carbon to graphitic carbon [6,7]. Because of their large surface area and conductivity, porous carbon materials have been extensively researched for use in energy devices such as batteries, supercapacitors, and fuel cells [8,9,10].…”

The effect of nitrogen on the synthesis of porous carbons by iron-catalyzed graphitization

“…9 Raw lignocellulosic biomasses such as wood or nut shells can generate graphitic carbons with very similar porosity and graphitic content but only if they are milled to fine powders before pyrolysis with iron. 10 In another example, glucose (soluble monosaccharide) and cellulose (insoluble polysaccharide) were shown to produce mesoporous carbons with very similar properties after iron-catalyzed graphitization under identical conditions. 11 In contrast, starch produced microporous carbons with very little graphitic content, despite starch being a polysaccharide comprised of glucose monomers, like cellulose.…”