Mechanochemical activation of humic acids in the brown coal

Skybová, M.; Turcaniova, L.; Čuvanová, S.; Zubrik, Anton; Hredzák, Slavomír; Hudymáčová, Ľ.

doi:10.1016/j.jallcom.2006.08.310

Cited by 18 publications

(8 citation statements)

References 10 publications

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“…In the FTIR spectrum of coal bituminous (Figure 2), a band at 1.600 cm -1 related to the stretching vibration of C=C aromatic bond was observed (Skybová, et al, 2007;Lobartini, et al, 1992). Although coals have aromatic rings in the chemical structure, the band at 3,040 cm -1 was not present, which indicated that aromatic structures in the coal had a high degree of condensation and substitutions.…”

Section: Resultsmentioning

confidence: 99%

“…This increases the yield of humic acids in the coals, also leading to higher extraction yields of these materials (Skybová, et al, 2007;Lobartini, et al, 1992). Coal oxidation processes are usually carried out with air at moderate temperatures or dilute solutions of H 2 O 2 , HNO 3 or KMnO 4 , in order to maximize the degree of formation of carboxylic and phenolic groups and minimize the decomposition of the organic matter to CO 2 .…”

Section: Introductionmentioning

confidence: 99%

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Effect of particle size and oxidant concentration in the yield of humic acids from mineral coal using response surface methodology

Pájaro-Payares

Espinosa-Fuentes

Colpas-Castillo

et al. 2017

Rev. Acad. Colomb. Cienc. Ex. Fis. Nat.

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Humic acids are produced by decomposition of organic soil material and from oxidation of mineral coals. In this study, the effect of oxidation and the yield of humic acids extracted from a sample of Colombian mineral coal were studied by response surface methodology (RSM). The variables used were: particle size (0.063, 0.106 and 0.150 mm), concentration of the oxidizing agent (KMnO 4 : 0.010, 0.020 and 0.050 M) and oxidation time (30, 60 and 90 minutes). The degree of oxidation was verified by infrared spectroscopy. Oxidation increased oxygen groups in the carbonaceous matrix, mainly due to oxidation of aliphatic components. Extraction yields above 24% were obtained with 0.063 mm particle size and 0.020 M KMnO 4 . © 2017. Acad. Colomb. Cienc. Ex. Fis. Nat.Key words: bituminous coal; humic acids; oxidation process; surface response; factorial design. Efecto del tamaño de partícula y la concentración del oxidante en el rendimiento de ácidos húmicos obtenidos de carbón mineral proveniente de Colombia usando la metodología de superficie de respuesta ResumenLos ácidos húmicos se producen por la descomposición de la materia orgánica de los suelos y por la oxidación de carbones minerales. En este estudio se analizó mediante superficies de respuesta el efecto de la oxidación en la extracción de ácidos húmicos de un carbón colombiano. Las variables de oxidación estudiadas fueron las siguientes: tamaño de partícula (0,063, 0,106 y 0,150 mm), concentración del agente oxidante (permanganato de potasio (KMnO 4 ): 0,010, 0,020 y 0,050 M) y tiempo de oxidación (30, 60 and 90 minutos). El grado de oxidación se verificó con espectroscopia infrarroja. La oxidación incrementó los grupos oxigenados en la matriz carbonácea debido, principalmente, a la oxidación de componentes alifáticos. Se obtuvieron porcentajes de extracción superiores a 24 % al usar partículas de 0,063 mm y KMnO 4 con 0,020 M.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of particle size and oxidant concentration in the yield of humic acids from mineral coal using response surface methodology

Pájaro-Payares

Espinosa-Fuentes

Colpas-Castillo

et al. 2017

Rev. Acad. Colomb. Cienc. Ex. Fis. Nat.

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“…The HA yield increased rapidly from 79.13% to 90.2% in the size range from 0.425-0.250 mm to 0.250-0.180 mm but did not increase thereafter. After the raw coal was ground, its specific surface area and pore structure increased [51], and the organic matter in the coal was mildly oxidized, leading to the breakage and deformation of weak chemical bonds and alkyl structure, the reduction of relative molecular mass, and an increase in the content of oxygen-containing functional groups [52]. Therefore, decreasing the coal sample size contributed not only to the contact between the KOH solution and the coal sample but also to the improvement in the HA yield.…”

Section: Effects Of the Water-to-coal Mass Ratio And Coal Sizementioning

confidence: 99%

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

et al. 2019

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Humic acid (HA) was extracted by a hydrothermal method from Huolinhe lignite from Inner Mongolia. The effects of the alkali-to-carbon mass ratio, water-to-coal mass ratio, reaction temperature, and reaction time on the HA yield were investigated. The physicochemical characterization of the products was performed, and the reaction mechanism was explored. Raw coal, HA, and residual coal were characterized using Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–VIS), elemental composition, and X-ray diffraction (XRD) analyses and compared to each other. The maximum HA yield (90.2%) was obtained from the 0.250–0.180 mm size fraction of the coal sample at a reaction temperature and time of 190 °C and 7 h. Proximate analysis proved that the ash and sulfur of lignite can be removed by hydrothermal treatment. Elemental analysis showed that the O/C and H/C ratios were highest for HA, followed by those for residual coal and raw coal, indicating an increase in the oxygen and hydrogen content of HA. FTIR and UV–VIS analyses showed that hydrothermal extraction destroyed the macromolecular structure of lignite. Moreover, the organics were degraded and hydrolyzed during the reaction process.

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“…Sugarcane bagasse is a source of vegetal fiber that has potential use on the industry of polymeric composites [9]. Sugarcane bagasse (SCB) produce humic acid (HA) after decomposition which have colloidal character and huge active surface which provide fine adsorptive properties [10]. Adsorptive features of HA allow to supply necessary micro-and macronutrients to plants and eliminating from the ground ionic and molecular impurities in the form of heavy metals [10,11].…”

Section: Introductionmentioning

confidence: 99%

Soil Amendments with Sugarcane Bagasse and its Effect on Soil Humic Acid Contents and Chinese Cabbage Growth Components

2019

ARTOAJ

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Sugarcane bagasse (SCB) which is a waste byproduct of sugarcane industry can be used as soil amendments to improve crop yield and provide reasonable economic means to recycle these wastes in an environment friendly manner. In this study experiments were conducted to test the rate of production of humic acid during the decomposition of SCB for 30 days and effect of SCB amendments on growth components of Chinese Cabbage (Brassica rapa, subsp. pekinensis). Humic acid were extracted using the classic alkali/acid fractionation method while FT-IR method was used to characterize humic acid. The results were shown that higher amount (0.2779g) of humic acid was extracted after 30 days, and small amount (0.0053g) was extracted from 0 day of SCB decomposition. The amount of humic acid extracted from SCB is significantly increased with respect to the time for decomposition of SCB. Growth performance of Chinese cabbage was recorded in terms of increase in plant height above ground, fresh and dry weight, root length, root fresh and dry weight. The experiment was conducted by 3 x 3 factorial designs employing three concentrations of SCB (0%, 2%, 5% and 10 %). The results showed that there is significant increase in plant growth components with increase of SCB concentration. It is recommended that application of SCB 10% will result in enhanced yield of Chinese cabbage. This may be due to high amount of humic acid produced by SCB after decomposition which leads to improve other soil characteristics.

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Mechanochemical activation of humic acids in the brown coal

Cited by 18 publications

References 10 publications

Effect of particle size and oxidant concentration in the yield of humic acids from mineral coal using response surface methodology

Effect of particle size and oxidant concentration in the yield of humic acids from mineral coal using response surface methodology

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

Soil Amendments with Sugarcane Bagasse and its Effect on Soil Humic Acid Contents and Chinese Cabbage Growth Components

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