scholarly journals Artichoke as a non-conventional precursor for activated carbon: Role of the activation process

2017 ◽  
Vol 11 (5) ◽  
pp. 677-688 ◽  
Author(s):  
Gamal M.S. ElShafei ◽  
Ibrahim M.A. ElSherbiny ◽  
Atef S. Darwish ◽  
Christine A. Philip
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.


2021 ◽  
Author(s):  
Petar Djinović ◽  
Janez Zavašnik ◽  
Janvit Teržan ◽  
Ivan Jerman

AbstractCeO2, V2O5 and CeVO4 were synthesised as bulk oxides, or deposited over activated carbon, characterized by XRD, HRTEM, CO2-TPO, C3H8-TPR, DRIFTS and Raman techniques and tested in propane oxidative dehydrogenation using CO2. Complete oxidation of propane to CO and CO2 is favoured by lattice oxygen of CeO2. The temperature programmed experiments show the ~ 4 nm AC supported CeO2 crystallites become more susceptible to reduction by propane, but less prone to re-oxidation with CO2 compared to bulk CeO2. Catalytic activity of CeVO4/AC catalysts requires a 1–2 nm amorphous CeVO4 layer. During reaction, the amorphous CeVO4 layer crystallises and several atomic layers of carbon cover the CeVO4 surface, resulting in deactivation. During reaction, V2O5 is irreversibly reduced to V2O3. The lattice oxygen in bulk V2O5 favours catalytic activity and propene selectivity. Bulk V2O3 promotes only propane cracking with no propene selectivity. In VOx/AC materials, vanadium carbide is the catalytically active phase. Propane dehydrogenation over VC proceeds via chemisorbed oxygen species originating from the dissociated CO2. Graphic Abstract


2019 ◽  
Vol 5 (2) ◽  
pp. 383-396 ◽  
Author(s):  
Anna Patrícya Florentino ◽  
Ahmed Sharaf ◽  
Lei Zhang ◽  
Yang Liu

Methanogenesis and enrichment of microorganisms capable of interspecies electron and/or hydrogen exchange was investigated with addition of granular activated carbon (GAC) to batch anaerobic digesters treating vacuum collected blackwater with high ammonia concentration.


RSC Advances ◽  
2015 ◽  
Vol 5 (41) ◽  
pp. 32626-32636 ◽  
Author(s):  
Yaxin Li ◽  
Xian Zhang ◽  
Ruiguang Yang ◽  
Guiying Li ◽  
Changwei Hu
Keyword(s):  

H3PO4promoted the decomposition of some species to form CO2and reacted with PBTRHR to form PH3.


2014 ◽  
Vol 486 ◽  
pp. 159-169 ◽  
Author(s):  
Pankaj Raizada ◽  
Pardeep Singh ◽  
Amit Kumar ◽  
Gaurav Sharma ◽  
Brijesh Pare ◽  
...  

2011 ◽  
Vol 19 (02) ◽  
pp. 147-168 ◽  
Author(s):  
GIANLUCA ELIA ◽  
A. MARGHERITA ◽  
G. SECUNDO ◽  
K. MOUSTAGHFIR

The pervasiveness of scientific developments has raised the role of entrepreneurship as a driver of socio-economic value. Higher education institutions are thus asked to create entrepreneurial mindset and competencies with the purpose to make students people able to proactively identify opportunities and transform them in market solutions. In particular, engineering education programs can be of relevance to develop technology entrepreneurship competencies through hands-on and experiential approaches. In such vein, this paper proposes a model of entrepreneurship education as an "activation" process which uses four critical levers with the purpose to infuse the essence of entrepreneurship in tomorrow's engineering professionals. The application of the model is exemplified through the analysis of a research training program grounded in the aerospace domain. The key features of the initiative are discussed in the perspective of exploring new models of entrepreneurial engineering education.


Author(s):  
S. Manocha ◽  
Parth Joshi ◽  
Amit Brahmbhatt ◽  
Amiya Banerjee ◽  
Snehasis Sahoo ◽  
...  

In the present work, a one step carbon activation process was developed by stabilized poly-blend. It is carbonized in nitrogen atmosphere and activated in steam in one step for known interval of times to enhance the surface area and develop interconnected porosity. The weight-loss behavior during steam activation of stabilized poly-blend at different temperatures, surface area and pore size distribution were studied to identify the optimum synthesis parameters. The results of surface characteristics were compared with those of activated carbon prepared by carbonization and activation in two steps. It was found that activation temperature has profound effect on surface characteristics. As activation temperature was raised from 800 °C to 1150 °C, surface area of activated carbon increased about three times. In addition to surface area, average pore diameter also increases with increasing activation temperature. Thus, activated carbon with high percentage of porosity and surface area can be developed by controlling the activation temperature during activation process.


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.


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