Fig 2 - available via license: CC BY-NC-ND
Content may be subject to copyright.
Source publication
Lignin as a by-product of the pulping process is less widely used for worth materials. In this study, the utilization of lignin by-product of the soda delignification process of coconut coir converted to the activated carbon by a simple precipitation method followed by the carbonization at various temperatures is presented. The by-product liquor of...
Context in source publication
Context 1
... The clear peak does not indicate the loss of carbon on the DTA graph because of the slow degradation rate of carbon up to the temperature at around 860 °C with the remaining weight at around 21.6 wt.% corresponds to the ash content. The visual appearance of dried lignin and carbonized lignin at temperatures of 500, 700, and 900 °C are shown in Fig. 2(a-d). The dried lignin has a brownishred appearance and bulky form. Carbonized lignin is black and shiner with the increase in carbonization temperature caused by the decomposition of the organic compound of some lignin constituents into volatile gases and solid carbon. TG-DTA measurement has confirmed the disappearing of the organic ...
Citations
... However, as an electrode for supercapacitors, the capability and usage cycle of manganese dioxide are still low because of its poor structural stability [17]. Moreover, carbon-based materials have a high surface area, porous structure, and good accessibility in the electrolyte [18]. So that the carbon-based material composited with MnO2 is a promising strategy to be used together to overcome each other limitations. ...
The investigation of biomass-based, cost-effective, efficient, and environmentally materials with high power density and fast ion/electron transfer is intensively carried out for the development of renewable energy storage devices. Pyrolysis and hydrothermal carbonization (HTC) are two common methods of thermochemical conversion to synthesize biomass-derived based carbon. Compared to the pyrolysis method, HTC is a more promising strategy because it can be carried out without a pre-drying process, has a high yield, low ash content, and requires a relatively low temperature (180-250 °C). The carbon produced from the HTC process is known as hydrochar. This study reports the acid-assisted hydrothermal carbonization temperature on the hydrochar properties and its application for supercapacitor electrodes. Hydrochar was synthesized from extracted avocado seed waste with potassium permanganate and sulfuric acid catalyst solution at 200 °C for 12 h. The effect of one- and two-stage HTC temperature on the hydrochar properties were compared. The hydrochar characterization includes yield, SEM, XRD, FTIR, and cyclic voltammetry analysis. According to the characterization and analysis results, hydrochar produced has the 3D porous network morphology and the highest specific capacitance of 73.54 F/g. In conclusion, hydrochar derived from avocado seed through the acid-assisted HTC can be a potential way for supercapacitor electrodes.
... In the process of taking long fibers, about 10.8% of the waste was produced in the form of short fibers that cannot be used for textile. Ramie stems waste includes biomass with its abundant availability in Indonesia, reaching 110.48 tons/year so which is potential for the manufacture of cellulose-based aerogel (Murdiyanto 2017;Widiyastuti et al. 2020). Ramie is classified as stem fiber which has a lower lignin content when compared to the fruit fiber group (Dey and Mandhyan 2016;Farias et al. 2017). ...
Oil spills on the seawater happened along the last decade needs to be addressed to prevent marine ecosystem destruction. The challenges encourage researchers to develop high-performance adsorbents. This study aims to investigate the adsorption capacity of magnetite-cellulose aerogel derived from Ramie stems in the oil-seawater mixture. The novelty of this research is the utilization of new and largely available ramie cellulose material combined with magnetite in simple alkali-urea method followed by coating using water repellant. Aerogel was synthesized by dissolving pulp of Ramie in NaOH-urea solution with urea addition of 3–6 g/g pulp and magnetite of 0–150 mg/g pulp. The mixtures were processed with sonication, coagulation, solvent exchange, freeze drying, and coating. The modified magnetite aerogel was analyzed for adsorption capacity, density, porosity, and measured contact angle. This research succeeded in synthesizing cellulose-magnetite aerogel from Ramie with density and porosity ranging from 0.11–0.22 gr/cm3 to 0.89–0.93, respectively. The characterization showed that the aerogels were arranged of macroporous structure and hydrophobic properties with a contact angle of 139°. The optimum adsorption capacity was 5.2 g diesel Dexlite/g aerogel and 7.2 g used lubricant oil/g aerogel at urea variations of 5 g/g pulp and magnetite 150 mg/g pulp. From this study, cellulose-magnetite aerogel from Ramie can be a solution to overcome the problem of oil spills with the advantages of being eco-friendly, abundant, and low cost.Graphical Abstract
... Lignin has been used as a carbon source on electrodes [23][24][25]. Lignin-derived carbon materials have also been combined with conducting polymers which have yielded high energy densities. Most of the studies report the advantage of lignin as a carbon precursor, or it is pretreated following with combination to conducting polymers and transition metal oxides to enhance their performance. ...
Lignin-based electrospun nanofiber composited with MnO2 mats is synthesized for electrocatalyst applications. Lignin-based nanofiber is produced from Sodium lignosulfonate (SLS) through electrospinning, using Polyvinyl acetate (PVA) as polymer followed by stabilization using iodine treatment. The composited process is observed by introducing KMnO4 following with hydrothermal process, and it is compared between before and after the electrospinning process. A conductivity, specific surface area, and morphology analysis confirm that the PVA:SLS mass ratio of 15:4.5 and 15:6 showed the best choice. In addition, x-ray diffraction exhibit that the sample composited with MnO2 either before or after electrospinning (pre- and post-electrospinning composite) has the same amorphous phase of α-MnO2. Consequently, lignin nanofiber with PVA:SLS mass ratio of 15:4.5 composited with MnO2 before the electrospinning process possesses has the best electrochemical properties with a current density of 1.5 mA/cm² and at potential applied of 0.4 V versus Ag/AgCl. Furthermore, the electron transferred, n occurred is 3.01, indicating the sample shows high potential to be used as an electrocatalyst following the two-electron pathway oxygen reduction reaction (ORR) mechanism.
... Nitrogen is generally used as dopant material due to its extra lone pairs of electrons during doping with carbon, thus accelerating the transfer of electrons from carbon to oxygen. Increased electron transfer can improve the electronic properties of carbon and increase ORR activity [7][8][9]. Several types of polymers can generally be used as nitrogen sources in non-precious metal catalysts, including polypyrrole, polyaniline, and melamine [10,11]. In general, the level of N affects the catalytic activity and provides many active sites, which theoretically will increase the reaction rate. ...
... Both samples determined the type IV of Brunauer's classification for the mixed character. The behavior reflects the coexistence of mesopores [8,9]. However, the CoFe-C-N composite particle showed a low amount of N 2 adsorption volume. ...
The objective of this research is to illustrate the effects of using transition metals and nitrogen-doped carbon obtained from the polymerization process. The pyrolysis method is chosen to optimize the role of each catalytic component such as metal precursors, nitrogen, and carbon source. Metal Precursors have distinct characteristics based on both electrochemical measurement and other characterizations. Based on Cyclic Voltammetry (CV) measurement, Ni–C–N material possesses the highest current density compared to other single metal-based catalysts. Therefore, in the utilization of dual metal catalysts, FeNi–C–N possesses the highest current density among other dual metals. The total metal loading of FeNi–C–N catalysts is 8.61% as obtained in Energy Dispersive X-Ray (EDX), which shows the optimal value to obtain the proper electrochemical properties. The formation of oxide compounds from the combination of dual metals acts as a catalyst performance enhancer. The CN bond seen in FTIR analysis shows the existence of bond interaction of C and N atoms after polymerization and pyrolysis processes. The FeNi–C–N sample also shows a more even nitrogen distribution and a more homogenous particle size on the surface of carbon, which allows a higher surface area in FeNi–C–N catalysts. It was proven by high specific surface area and pore volume which enhance the ORR activity via a two-step two-electron pathway.
... This study concluded that PVOH/lignin could be an excellent precursor for carbon fibers. Another study reported that the carbonized lignin had mesopores and an amorphous graphitic structure [25]. ...
A polyvinyl alcohol (PVOH)/lignin nanofiber was prepared by the electrospinning method as a precursor for biodegradable and low-cost carbon fibers. PVOH 15% was dissolved in water, and various concentration of lignin (5, 10, 15, 20, and 25%) was added. The presence of lignin in PVOH solution increased the viscosity and conductivity. From SEM analysis, PVOH solution produced smooth fiber, whereas the addition of lignin produced fibers in bead forms. The presence of lignin above 20% in PVOH did not produce spun-fiber. FTIR analysis confirmed that lignin was able to form hydrogen bonds with PVOH. TGA analysis showed that PVOH/lignin nanofibers had the highest residual mass, i.e., 40% at 600 °C. The morphology of the carbon fibers showed flake forms with many pores and had 58.07% carbon content.
The innovation of catalyst material for oxygen reduction reaction with a combination of metal precursors had been successfully synthesized using a variety of templates and post-treatment. The combination of two metal precursors consisting of transition metals (such as Fe, Ni, and Co) with the same metal ratio of 1:1 may affect the catalytic activity and physical properties. This research used 2,6-diaminopyridine as nitrogen-containing carbon material acting as a nitrogen and carbon source. This study used two types of hard templates which were LUDOX HS-40 colloidal silica and Montmorillonite K10 (MMT-K10) to optimize a dual metal with a porous nitrogen-doped catalyst. In addition, this research used a pyrolysis process at a temperature of 800 °C for 2 h within a nitrogen atmosphere. After that, post-treatment was carried out by leaching acid using a 0.5 M H2SO4 solution for 2 h. As a result, LUDOX HS-40 template has provided an advantage in increasing the oxygen reduction reaction (ORR) activity. In addition, the FeNi/CN-L catalyst yielded the highest catalytic activity with an electron transfer number of 3.61. LUDOX HS-40 template will make the shape of the FeNi/CN-L catalyst particles become irregular which in turn will increase ORR activity. This phenomenon is due to the electrostatic force from carbon to metal ions in which metal interactions with carbon particles occur. Thus, it can increase catalytic activity during the oxygen reduction reaction.
The aim of this study was to produce activated carbon (AC) from lignin obtained with deep eutectic solvents (DESs) of choline chloride–lactic acid. For this, lignin particles were produced using the DES. The DES lignin (DES‐Lig) was modified with zinc dichloride, and the lignin activated carbon (lig‐AC) was produced by carbonization at 600 and 900 °C. In this study, the AC obtained from the commercial lignin was also used to determine the changes in the lig‐AC from the lignin obtained with the DES. The material properties were investigated using Brunauer–Emmett–Teller (BET) surface analysis, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), and the structural properties were investigated with X‐ray diffractometry (XRD) of the lig‐ACs. The commercial and DES‐Lig exhibited different microscopic morphologies. The surface area of the samples generally ranged from 504 to 698 g/cm², and they included both micro‐ and mesopores according to SEM characterization. The XRD analysis showed that the ACs obtained have an amorphous structure, and thermogravimetric analysis of the ACs exhibited similar thermal behavior to that in the literature. The best morphological structure was found in the ACs prepared from lignin with the DES at 900 °C according to the results of SEM, TGA, XRD and BET analysis. The proximate analysis showed that the best ACs contain 1.5% moisture, 6.5% volatile matter, 5.5% ash content and 86.5% fixed carbon. According to the elemental analysis, the amounts of essential elements, including C, H, N and O were investigated, and the best activated carbon was determined to be the DES‐Lig at 900 °C according to BET and the proximate fixed carbon results.
Tremendous research efforts are being devoted towards extracting sustainable electricity from the pressure-driven flow of water through artificially fabricated channels of nanometer dimensions. Here, we demonstrate that the biofluidic channels...
As the second most abundant bio-resource and as a byproduct of lignocellulose material processing, alkali lignin has to become a quantitative issue due to its difficulties to handle. On the other hand, lignin has high natural carbon contents, so it has the potential to act as a precursor for carbon materials. However, many previous researchers do three steps to transform it into high porous carbon: precipitation by reducing the alkaline compound, calcination to transform it into carbon, and carbon activation by adding alkaline compound again. In this study, the porous carbon material from alkali lignin in a one-step process for use as an electrode in supercapacitor and electrocatalyst is examined. The evaporation and especially carbonation temperature are studied to obtain the high porous carbon. After varying calcination temperatures, the carbon material's characterization was investigated to examine porosity, morphology, crystallinity, specific electrocapacity, and Oxygen Reduction Reaction (ORR) electrocatalyst activity. The carbon derived from Na-lignin via calcination at 700 °C had the highest electrocapacity of 168.29 F/g. The electron transformed number is 2.23, indicating that the carbon derived from Na-lignin via calcination is promising for an electrode agent of supercapacitor and electrocatalyst for ORR.
In this study, electrospinning technology, iodine treatment, thermal stabilizing, and carbonization processing were applied to produce lignosulfonate-based carbon nanofibers. The porous structure of the produced lignosulfonate-based carbon nanofibers primarily contained mesopores and a relatively small amount of micropores. Moreover, the increasing amount of sodium lignosulfonate (SLS) as lignin source was also studied. The diameter of fibre was impacted by the additional of SLS that may cause by the alkali content of SLS itself. In electrospun nanofiber phase, the presence of SLS reduce the specific surface area, but contrary increase the specific surface area after the nanofibers were carbonized into carbon nanofiber. Lignosulfonate-based activated carbon fibres can be used as a highly efficient adsorption and filtration material, and further development of its applications would be valuable.
