Activated carbon is generally recognized as an applicable material for gas or liquid adsorption and electrochemical devices, such as electric double-layer capacitors (EDLCs). Owing to the continuous increase in its price, research aimed at discovering alternative materials and improving its fabrication yield is important. Herein, organic pigments were ingeniously employed to enhance the fabrication of high-surface-area activated carbon with remarkable efficiency. Moreover, the focus was centered on the assessment of activated carbon derived from 2,9-dimethylquinacridone, also known as CI Pigment Red 122 for its capacity to adsorb tetracycline (TC) and its applicability as an electrode material for EDLCs. Activating these organic pigments with varying potassium hydroxide ratios allowed the fabrication of activated carbon with a higher yield than that for conventional activated carbon. Furthermore, it was confirmed that activated carbon with a very high specific surface area can be efficiently fabricated, demonstrating a remarkable potential in various application fields. Notably, this activated carbon exhibited an impressive maximum specific surface area and a total pore volume of 3,935 m2/ g and 2.324 cm3/ g, respectively, showcasing its substantial surface area and distinctive porous characteristics. Additionally, the Langmuir and Freundlich isotherm models were employed to examine the TC adsorption on the activated carbon, with the Langmuir model demonstrating superior suitability than the Freundlich model. Furthermore, the electrochemical performance of an activated carbon-based electrode for EDLCs was rigorously evaluated through cyclic voltammetry. The specific capacitance exhibited a considerable increase in proportion to the expanding specific surface area of the activated carbon.

The study investigated a method of synthesizing a pitch suitable for making activated carbon using fluid catalytic crackingdecant oil (FCC-DO), a high-purity carbon precursor from oil refining. We kept the reaction time and catalyst amount constant while varying the temperature to investigate its impact on pitch synthesis and the resulting physical and activation properties. Previous research established that materials added during pitch synthesis can affect the properties of both the pitch and resulting activated carbon. This study examined the addition of polyethylene terephthalate (PET) to FCC-DO-based pitch. The results indicated significant changes in properties with PET addition and temperature variation that ensured stable activated carbon quality. At temperatures of 390 °C or higher, the specific surface area of the activated carbon stabilized between 2680 and 2740 m2/ g. Waste PET, a recyclable plastic, was chosen due to its compatibility and thermodynamic suitability for pitch synthesis. Importantly, adding PET didn't generate additional waste or degrade the physical properties of the activated carbon.

Pyrolysis fuel oil (PFO) is used for the manufacturing of high-purity pitch for carbon precursor due to its high carbon content, high aromaticity, and low heterogeneous element and impurity content. Pitch is commonly classified with its softening point, which is most considerable physical property affecting to various characteristics of the carbon materials based on pitch, such as electrical and thermal conductivity, mechanical strength, and pore property. Hence, the softening point should be controlled to apply pitch to produce various carbon materials for different applications. Previous studies introduce reforming process under high pressure and two step heat treatment for the synthesis of pitch with high softening point from PFO. These methods lead to a high process cost; therefore, it is necessary to develop a process to synthesize the pitch with high softening point by using energy effective process at a low temperature. In this study, waste polyethylene terephthalate (PET) was added to control the softening point of PFO-based pitch. The pitch synthesized by the heat treatment with the addition of PET showed the softening point higher than that of the pitch synthesized with only PFO. The softening point of PFObased pitch synthesized at 420 °C was 138.3 °C, while that of the pitch synthesized by adding PET under the same process conditions was 342.8 °C. It is proposed that the effect of the PET addition on the increase in the softening point was due to the radicals generated from thermal degradation of PET. The radicals from PET react with the PFO molecules to promote the polymerization and finally increase the molecular weight and softening point of the pitch. In addition, activated carbon was prepared by using the pitch synthesized by adding PET, and the results showed that the specific surface area of the activated carbon increased by the addition of PET. It is expected that the pitch synthesis method with PET addition significantly contributes to the manufacture of pitch and activated carbon.

High surface carbon aerogels with hierarchical and tunable pore structure were prepared using ionic liquid as carbon precursor via a simple salt templating method. The as-prepared carbon aerogels were characterized by nitrogen sorption measurement and scanning electron microscopy. Through instant visual observation experiments, it was found that salt eutectics not only serve as solvents, porogens, and templates, but also play an important role of foaming agents in the preparation of carbon aerogels. When the pyrolyzing temperature rises from 800 to 1000°C, the higher temperature deepens the carbonization reaction further to form a nanoporous interconnected fractal structure and increase the contribution of super-micropores and small mesopores and improve the specific surface area and pore volume, while having few effects on the macropores. As the mass ratio of ionic liquid to salt eutectics drops from 55% to 15%, that is, the content of salt eutectics increases, the salt eutectics gradually aggregate from ion pairs, to clusters with minimal free energy, and finally to a continuous salt phase, leading to the formation of micropores, uniform mesopores, and macropores, respectively; these processes cause BET specific surface area initially to increase but subsequently to decrease. With the mass ratio of ionic liquids to salts at 35% and carbonization temperature at 900°C, the specific surface area of the resultant carbon aerogels reached 2309 m2 g–1. By controlling the carbonization temperature and mass ratio of the raw materials, the hierarchically porous architecture of carbon aerogels can be tuned; this advantage will promote their use in the fields of electrodes and adsorption.

This study is performed to fabricate a Ti porous body by freeze drying process using titanium hydride (TiH2) powder and camphene. Then, the Ti porous body is employed to synthesize carbon nanotubes (CNTs) using thermal catalytic chemical vapor deposition (CCVD) with Fe catalyst and methane (CH4) gas to increase the specific surface area. The synthesized Ti porous body has 100 μm-sized macropores and 10-30 μm-sized micropores. The synthesized CNTs have random directions and are entangled with adjacent CNTs. The CNTs have a bamboo-like structure, and their average diameter is about 50 nm. The Fe nano-particles observed at the tip of the CNTs indicate that the tip growth model is applicable. The specific surface area of the CNT-coated Ti porous body is about 20 times larger than that of the raw Ti porous body. These CNT-coated Ti porous bodies are expected to be used as filters or catalyst supports.