scholarly journals Bio-Adsorbent Derived from Sewage Sludge Blended with Waste Coal for Nitrate and Methyl Red Removal: Synthesis, Oxidation, Performance and Environmental Consideration

Author(s):  
John Longo Masengo ◽  
Jean Mulopo

Abstract Low-cost bio-adsorbents were synthesized using two types of sewage sludge: D, which was obtained during the dissolved air flotation stage, and S, which was a mixture of primary and secondary sludge from the digestion and dewatering stages. The sewage sludge was mixed with waste coal before being activated with Potassium Hydroxide (KOH) and oxidized with ammonium persulfate (APS). The nitrate and methyl red removal capacities of the synthesized bio-adsorbents were evaluated and compared to those of industrial activated charcoal. The oxidation surface area of bio-adsorbents derived from sludge S shrank by six fold after modification, while those derived from D only varied narrowly from 312,72 m2/g to 282,22 m2/g, but surface modification had no effect on inorganic composition in either case. The adsorption of nitrate and methyl red (MR) was performed in batch mode, and the removal processes followed the pseudo second order kinetic model and the Langmuir isotherm fairly well. The adsorption capacities of nitrate and MR were higher at pH=2 and pH=4, respectively. The total nitrate Langmuir adsorption potential was DC-5-750 (26,735 mg/g) > commercial activated carbon (Com-AC) (20,61 mg/g) > DC-55-750M1 (17,06 mg/g), and for MR, Com-AC (196,07 mg/g) > DC-5-750M2 (175 mg/g).Statement of Novelty: This paper examines how the chemical structure of activated carbon derived from sewage sludge and blended with waste coal is altered during the chemical activation process to provide the optimal porous surface for nitrate and methyl red adsorptive remediation. The formation of carboxylic sites or the transformation of oxygen sites to carboxylic sites is the aim of the oxidation process of activated carbon in general. Ammonium peroxydisulfate was chosen because of its ability to oxidize the surface without significantly altering the porous structure and increase surface acidity by increasing carboxylic group presence. There are no studies that we are aware of that use ammonium peroxydisulfate to oxidize activated carbon from sewage sludge blended with waste coal

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1377 ◽  
Author(s):  
Ruoke Ma ◽  
Xianxian Qin ◽  
Zhigao Liu ◽  
Yunlin Fu

Activated carbon fiber was prepared from liquefied wood by chemical activation with ZnCl2 (Z-LWACF) at different impregnation ratios, with a particular focus on its adsorption property, kinetic and isotherm. The characterization and properties of Z-LWACFs were investigated by nitrogen adsorption/desorption, X-ray photoelectron spectroscopy (XPS), methylene blue (MB) and iodine adsorption. Two activation process methods were employed to prepare Z-LWACF and contrasted with others fibers. The results showed that the Z-LWACF obtained by one-step ZnCl2 activation present higher yields and specific surface area than others fibers. Besides, the change of MB adsorption value at different impregnation ratios was consistent with pore structure distribution above 1.5 nm pore size, indicating that larger micropores (1.5 to 2 nm) and mesopores played a major role in the MB adsorption by Z-LWACF. The kinetics of MB adsorption process was found to follow the pseudo-second-order kinetic model and the adsorption rate was controlled by chemisorption. It was also found that MB adsroption by Z-LWACF belonged to monolayer adsorption and Z-LWACF was easy to adsorb MB.


2017 ◽  
Vol 8 (2) ◽  
pp. 192-201 ◽  
Author(s):  
Sicong Yao ◽  
Meicheng Wang ◽  
Jilong Liu ◽  
Shuxiong Tang ◽  
Hengli Chen ◽  
...  

Abstract Activated carbons were prepared from sewage sludge by chemical activation with pyrolusite (PAC) to develop an efficient adsorbent for phosphate removal from aqueous solution. One percent (wt.) pyrolusite addition was proved to have an important effect on pore formation of the produced carbon. PAC showed 17.06% larger Brunauer–Emmett–Teller (BET) surface area than the sewage sludge-based activated carbon without modification (SAC). The adsorption results showed that the phosphate removal by PAC was 13% higher than SAC's. The adsorption experiments also showed that PAC had very good performance with high phosphate removal rate (ca. 90%) in a wide pH range (pH = 4–8), and could be stable after 30 min reaction. Adsorption isotherm and kinetics studies demonstrated that phosphate adsorption onto the modified adsorbent was well fitted by the Langmuir isotherm and could be described by the pseudo-second-order kinetic model. The modified sewage sludge-based activated carbons were effective and alternative adsorbents for the removal of phosphorus from aqueous solution due to their considerable adsorptive capacities and the low-cost renewable sources.


2020 ◽  
Vol 82 (9) ◽  
pp. 1932-1949
Author(s):  
Mondira Bardhan ◽  
Tamanna Mamun Novera ◽  
Mumtahina Tabassum ◽  
Md. Azharul Islam ◽  
Ali H. Jawad ◽  
...  

Abstract In this study, activated carbon (AC) was prepared from agro-waste betel nut husks (BNH) through the chemical activation method. Different characterization techniques described the physicochemical nature of betel nut husks activated carbon (BNH-AC) through Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), and pH point of zero charge. Later, the produced AC was used for methylene blue (MB) adsorption via numerous batch experimental parameters: initial concentrations of MB dye (25–250 mg/L), contact time (0.5–24 hours) and initial pH (2–12). Dye adsorption isotherms were also assessed at three temperatures where the maximum adsorption capacity (381.6 mg/g) was found at 30 °C. The adsorption equilibrium data were best suited to the non-linear form of the Freundlich isotherm model. Additionally, non-linear pseudo-second-order kinetic model was better fitted with the experimental value as well. Steady motion of solute particles from the boundary layer to the BNH-AC's surface was the possible reaction dynamics concerning MB adsorption. Thermodynamic study revealed that the adsorption process was spontaneous and exothermic in nature. Saline water emerged as an efficient eluent for the desorption of adsorbed dye on AC. Therefore, the BNH-AC is a very promising and cost-effective adsorbent for MB dye treatment and has high adsorption capacity.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2951
Author(s):  
Mirosław Kwiatkowski ◽  
Jarosław Serafin ◽  
Andy M. Booth ◽  
Beata Michalkiewicz

This paper presents the results of a computer analysis of the effect of activation process temperature on the development of the microporous structure of activated carbon derived from the leaves of common polypody (Polypodium vulgare) via chemical activation with phosphoric acid (H3PO4) at activation temperatures of 700, 800, and 900 °C. An unconventional approach to porous structure analysis, using the new numerical clustering-based adsorption analysis (LBET) method together with the implemented unique gas state equation, was used in this study. The LBET method is based on unique mathematical models that take into account, in addition to surface heterogeneity, the possibility of molecule clusters branching and the geometric and energy limitations of adsorbate cluster formation. It enabled us to determine a set of parameters comprehensively and reliably describing the porous structure of carbon material on the basis of the determined adsorption isotherm. Porous structure analyses using the LBET method were based on nitrogen (N2), carbon dioxide (CO2), and methane (CH4) adsorption isotherms determined for individual activated carbon. The analyses carried out showed the highest CO2 adsorption capacity for activated carbon obtained was at an activation temperature of 900 °C, a value only slightly higher than that obtained for activated carbon prepared at 700 °C, but the values of geometrical parameters determined for these activated carbons showed significant differences. The results of the analyses obtained with the LBET method were also compared with the results of iodine number analysis and the results obtained with the Brunauer–Emmett–Teller (BET), Dubinin–Radushkevich (DR), and quenched solid density functional theory (QSDFT) methods, demonstrating their complementarity.


Author(s):  
Nawwarah Mokti ◽  
Azry Borhan ◽  
Siti Nur Azella Zaine ◽  
Hayyiratul Fatimah Mohd Zaid

The use of an activating agent in chemical activation of activated carbon (AC) production is very important as it will help to open the pore structure of AC as adsorbents and could enhance its performance for adsorption capacity. In this study, a pyridinium-based ionic liquid (IL), 1-butylpyridinium bis(trifluoromethylsulfonyl) imide, [C4Py][Tf2N] has been synthesized by using anion exchange reaction and was characterized using few analyses such as 1H-NMR, 13C-NMR and FTIR. Low-cost AC was synthesized by chemical activation process in which rubber seed shell (RSS) and ionic liquid [C4Py][Tf2N] were employed as the precursor and activating agent, respectively. AC has been prepared with different IL concentration (1% and 10%) at 500°C and 800°C for 2 hours. Sample AC2 shows the highest SBET and VT which are 392.8927 m2/g and 0.2059 cm3/g respectively. The surface morphology of synthesized AC can be clearly seen through FESEM analysis. A high concentration of IL in sample AC10 contributed to blockage of pores by the IL. On the other hand, the performance of synthesized AC for CO2 adsorption capacity also studied by using static volumetric technique at 1 bar and 25°C. Sample AC2 contributed the highest CO2 uptakes which is 50.783 cm3/g. This current work shows that the use of low concentration IL as an activating agent has the potential to produce porous AC, which offers low-cost, green technology as well as promising application towards CO2 capture.


2018 ◽  
Vol 36 (3-4) ◽  
pp. 1066-1099 ◽  
Author(s):  
Radia Labied ◽  
Oumessaad Benturki ◽  
Adh’ Ya Eddine Hamitouche ◽  
André Donnot

In aqueous solutions, hexavalent chromium Cr(VI) was successfully removed by activated carbon “ Z. jujuba rubidium carbonate-activated carbon” obtained from waste lignocellulosic material ( Ziziphus jujuba cores). Rubidium carbonate was used to prepare Z. jujuba rubidium carbonate-activated carbon by chemical activation using a 1:1 w/w ratio. Our results indicate that the obtained surface area of the activated carbon was equal to 608.31 m2/g. The adsorption study of Cr(VI) was investigated under batch conditions at constant stirring speed (220 r/min). Factors such as pH (1–6), temperature (20–40°C), adsorbent concentration (0.5–3 g/l), and initial Cr(VI) concentration (50–500 mg/l) were all studied to attain the maximum removal efficiency. Prior to the adsorption process, the morphology, elementary composition, and loss mass of activated carbon were characterized using scanning electron microscopy, X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Fourier transform infrared analysis of the adsorbent demonstrated the presence of key functional groups associated with the adsorption phenomenon such as those of hydroxyl and aromatic groups. The obtained results showed that the optimal conditions for a maximum adsorption efficiency are 2 for pH, 1 g/l for activated carbon dosage and 100 mg/l for Cr(VI) concentration. The removal percentage increased from 27.2 to 62.08%. The kinetic sorption was described by a pseudo-second-order kinetic equation ( R2 ≈ 0.995). The Tóth ( R2 = 0.997) and Elovich models were best to explain the sorption phenomenon. Thermodynamic studies showed that the adsorption of Cr(VI) onto activated carbon was feasible, spontaneous, and endothermic at 20–40°C. This novel Z. jujuba rubidium carbonate-activated carbon derived from Z. jujuba core has been found to be effective for the removal of Cr(VI) and not harmful to the ecosystem.


2014 ◽  
Vol 875-877 ◽  
pp. 196-201 ◽  
Author(s):  
Mohd Faisal Taha ◽  
Ahmad S. Rosman ◽  
Maizatul S. Shaharun

The potential of rice husk-based activated carbon as an alternative low-cost adsorbent for the removal of Pb (II) ion from aqueous solution was investigated. Rice husk-based activated carbon was preparedviachemical activation process using NaOH followed by the carbonization process at 500°C. Morphological analysis was conducted using field-emission scanning electron microscope /energy dispersive X-ray (FESEM/EDX) on three samples, i.e. raw rice husk, rice husk treated with NaOH and rice husk-based activated carbon. These three samples were also analyzed for their C, H, N, O and Si contents using CHN elemental analyzer and FESEM/EDX. The textural properties of rice husk-based activated carbon, i.e. surface area (253 m2/g) and pore volume (0.17 cm2/g), were determined by N2adsorption. The adsorption studies using rice husk-based activated carbon as an adsorbent to remove Pb (II) ion from aqueous solution were carried out at a fixed initial concentration of Pb (II) ion (150 ppm) with varying adsorbent dose as a function of contact time at room temperature. The concentration of Pb (II) ion was determined by atomic absorption spectrophotometer (AAS). The removal of Pb (II) ion from aqueous solution increased from 35 % to 82 % when the amount of rice husk-based activated carbon was increased from 0.05 g to 0.30 g. The equilibrium data obtained from adsorption studies was found to fit both Langmuir and Freundlich adsorption isotherms.


2015 ◽  
Vol 1107 ◽  
pp. 347-352 ◽  
Author(s):  
Collin Glen Joseph ◽  
Duduku Krishniah ◽  
Yun Hin Taufiq-Yap ◽  
Masnah Massuanna ◽  
Jessica William

Abstract. Waste tires, which are an abundant waste product of the automobile industry, were used to prepare activated carbon by means of physical and chemical activation. A two-stage process was used, with a semi-carbonization stage as the first stage, followed by an activation stage as the second stage.All experiments were conducted in a laboratory-scale muffle furnace under static conditions in a self-generated atmosphere. During this process, the effects of the parametric variables of semi-carbonization time (for the physical activation process), activation time and temperature and impregnation ratios (for the chemical activation process) on the percentage yield were studied and compared. Varying these parametric variables yielded interesting results, which in turn affected the adsorption process of 2,4-DCP, which was the simulated pollutant in aqueous form. The optimized percentage yields of activated carbon that were obtained were 41.55% and 44.88% ofthe physical and chemical activation treatment processes respectively.Keywords: Physical activation, chemical activation, waste rubber tires, 2,4-dichlorophenol, activated carbon.


2014 ◽  
Vol 896 ◽  
pp. 179-182 ◽  
Author(s):  
Erman Taer ◽  
Iwantono ◽  
Saidul Tua Manik ◽  
R. Taslim ◽  
D. Dahlan ◽  
...  

Binderless activated carbon monoliths (ACMs) for supercapacitor electrodes were prepared from sugarcane bagasse by two different methods of physical and combination of physical-chemical activation process. The CO2 gas was used as physical activation agent and 0.3 M KOH was chosen as chemical activation agent. The ACMs were tested as electrodes in two-electrode systems of the coin tape cell supercapacitor that consists of stainless steel as current collectors and 1 M H2SO4 as an electrolyte. The improving of resistive, capacitive and energy properties of combination of physical-chemical ACMs electrodes were shown by an impedance spectroscopy, a cyclic voltammetry and a galvanostatic charge-discharge method. The improving of resistive, capacitive and energy properties as high as 1 to 0.6 Ω, 146 to 178 F g-1, 3.83 to 4.72 W h kg-1, respectively. The X-ray diffraction analysis and field emission scanning electron microscope were performed to characterize the crystallite and morphology characteristics. The results showed that the combination of physical-chemical activation process have given a good improving in performance of the bagasse based ACMs electrodes in supercapacitor application.


Sign in / Sign up

Export Citation Format

Share Document