Preparation of Activated Carbon from Korean Anthracite: Simultaneous Control of Ash Reduction and Pore Development

Abstract

Anthracite stands as a valuable precursor for carbon materials, owing to its high carbon content. However, producing activated carbon from anthracite presents significant challenges due to its elevated ash content (23–40 wt%) and crystalline nature. The high ash content not only fails to contribute to the activation process but also obstructs pore formation on the carbon surface. To address these challenges, this study explores the preparation of activated carbon from anthracite using KOH activation. This method demonstrates remarkable efficacy in enhancing reactivity beyond the inherent physical properties of anthracite. In contrast to physical activation, the utilization of KOH as a chemical agent substantially enhances the specific surface area, resulting in a production yield of 62% and a specific surface area that reaches up to 1596 m2/g at a KOH/anthracite weight ratio of 4.0. Moreover, rinsing the activated sample with tap water achieves an ash removal rate of about 37.9%, surpassing twice the rate achieved through acid pretreatment (67.0%). A noteworthy observation from this study is the substantial reduction in the content of major ash components, such as silicon (Si) and aluminum (Al), both of which are prominent constituents in anthracite ash. Following KOH activation, their levels decrease by approximately 54% to 65%, respectively. These findings highlight the potential of utilizing available anthracite, even with elevated ash content, as a superior carbon material. Fundamentally, the KOH activation method serves a dual purpose: it effectively reduces ash content and promotes pore creation within a highly alkaline environment. This dual advantage positions the method as a promising approach for the production of top-tier activated carbon.

A Study on the Adsorption of Rhodamine B onto Adsorbents Prepared from Low-Carbon Fossils: Kinetic, Isotherm, and Thermodynamic Analyses

“…The low elemental carbon content of the SA sample resulted in a high mineral content of up to 43.4 wt.%. This high ash content may cause pore clogging in the sample structure, hindering the reaction between the adsorbate and the adsorbent [ 17 ]. Furthermore, the ICP method was used to determine the weight percentage of certain elements in the ashes of the adsorbents.…”

The Ability of Sub-Bituminous Coal Activated with NaOH in Removal of Mercury: Equilibrium and Isotherm Study

“…This process may increase the porosity and surface liveliness of the coal. The reaction of coal with NaOH can cause the removal of K and Al ions and can also cause the removal of these ions, as well as affect the mineral structure and surface liveliness through changes in the molecular structure of the coal, especially the organic part [27,28].…”

Decolorization of Lactose-6-Phosphate Solutions Using Activated Carbon

“…The decolorization of LaP1 and LaP2 solutions was prepared using the methodology reported by Zhang et al [33,34], with some modifications. These solutions were decolorized using activated carbon (Darco G60,-100 mesh, powder, Aldrich Chemical Company, St. Louis, MO, USA).…”