Fast preparation of carbon spheres from enzymatic hydrolysis lignin: Effects of hydrothermal carbonization conditions

Abstract

This study explores the effect of carbon sphere preparation conditions on the morphology of the carbon spheres and the micropore development by fast potassium hydroxide activation via microwave heating. Enzymatic hydrolysis lignin is used as the precursor for carbon sphere preparation via environmentally friendly hydrothermal carbonization. The effects of various carbonization temperatures, carbonization times and reaction concentrations on the physical morphology of the carbon sphere surfaces are investigated. The Brunauer-Emmett-Teller surface area, yield and scanning electron microscopic images are used to characterize the carbon spheres. High carbonization temperatures and times result in large particle sizes, high sphericity, uniform size, and high dispersity of the carbon spheres. The best carbon spheres are obtained at 270 °C for 7 hours with a reaction concentration of 0.06 g ml−1 and a particle size of 3–6 μm. After activation, the Brunauer-Emmett-Teller surface area of the activated carbon spheres increases from 248 m2 g−1 to 1278 m2 g−1. Carbon spheres activated by treatment with fast potassium hydroxide and microwave heating can develop micropores that enhance the adsorptive capacity for small molecules, such as gases. Enzymatic hydrolysis lignin-derived carbon spheres formed via hydrothermal carbonization should be potentially sustainable materials applicable in energy and environmental fields.

A Review What Is Hydrothermal ?

“…Pada pelepasan material lama dan pengendapan material baru menjadi ciri aktivitas hydrothermal (49)(50)(51)(52),serta banyak mineral pembentuk proses yang melibatkan solusi, termasuk pelapukan dan diagenesa (18; 53). Hydrothermal merupakan suatu proses pembentukan mineral yang terjadi disekitar sumber dari panas bumi didalam kulit bumi yang terjadi akibat adanya injeksi dari magma terhadap air dengan kata lain terjadi pelarutan oleh magma sisa yang bercampur dengan air tanah sehingga mengalami pengkristalan (54)(55)(56)(57)(58)(59)…”

Carbon Nano-Sphere Derived From Crop Residues by Acidic Lithium Bromide Treatment and as an Excellent Adsorbent to Both Heavy Ions and Methyl Orange

“…The fabrication of carbon spheres has attracted extensive attention in the eld of materials science. Due to its unique properties, such as surface functional chemical groups, surface area and controllable particle size, carbon spheres have broad application prospects in catalysis, electrochemical conversion, energy storage and environmental puri cations (Bai et al, 2018;Liang et al, 2008;Mao et al, 2018;Mi et al, 2008;Siyasukh et al, 2018;Tian et al, 2019). The properties of carbon spheres were highly relied on the synthesis method.…”

“…The properties of carbon spheres were highly relied on the synthesis method. Over the past decades, many researchers made great efforts on the synthesis methods of carbon spheres, such as the template methods (hard template and soft template), the hydrothermal carbonization method and the microemulsion polymerization method (Fechler et al, 2013;Mao et al, 2018;Mi et al, 2008). Template methods involved multi-steps: a) the synthesis of the template, b) the preparation of the carbon precursors, c) the pyrolysis carbonization process, d) template removal in a harsh condition (Claesson & Philipse, 2005).…”

“…The hydrothermal carbonization methods were commonly performed at temperature from 200°C to 250°C for about 12 h to 48 h (Sevilla & Fuertes, 2009;Simsir et al, 2017). Many biomass derived carbon precursors could be transformed to spherical carbon through the HTC methods, such as glucose, fructose and sucrose (Mao et al, 2018;Mi et al, 2008;Nizamuddin et al, 2017;Tian et al, 2019). However, the raw lignocellulose was resistant to hydrothermal treatment and hardly produced the carbon spheres during HTC process (Simsir et al, 2017), (Zhang et al, 2019b).…”

Photocatalytic performance of ZnO carbon composites for the degradation of methyl orange dye

“…They are made up of number of concentric carbon layers, where CS having diameter less than 1000 nm are observed to have similar properties such as graphene and/or fullerene [27]. The CS can be used as a supporting template for synthesizing various composite materials due to its unique properties which mainly include high surface area, high structural stability and many other properties [28]. Hence it is interesting to understand the role of CS while synthesizing various nano composites metal oxides and their related applications in various fields [29].…”