scholarly journals Sorption Characteristics of Mixed Molecules of Glutaraldehyde from Water on Mesoporous Acid-Amine Modified Low-Cost Activated Carbon: Mechanism, Isotherm, and Kinetics

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Mukosha Lloyd ◽  
Onyango S. Maurice ◽  
Ochieng Aoyi ◽  
Taile Y. Leswifi

The environmental discharge of inefficiently treated waste solutions of the strong biocide glutaraldehyde (GA) from hospitals has potential toxic impact on aquatic organisms. The adsorption characteristics of mixed polarized monomeric and polymeric molecules of GA from water on mesoporous acid-amine modified low-cost activated carbon (AC) were investigated. It was found that the adsorption strongly depended on pH and surface chemistry. In acidic pH, the adsorption mechanism was elaborated to involve chemical sorption of mainly hydroxyl GA monomeric molecules on acidic surface groups, while in alkaline pH, the adsorption was elaborated to involve both chemical and physical sorption of GA polymeric forms having mixed functional groups (aldehyde, carboxyl, and hydroxyl) on acidic and amine surface groups. The optimum pH of adsorption was about 12 with significant contribution by cooperative adsorption, elucidated in terms of hydrogen bonding and aldol condensation. Freundlich and Dubinin-Radushkevich models were fitted to isotherm data. The adsorption kinetics was dependent on initial concentration and temperature and described by the Elovich model. The adsorption was endothermic, while the intraparticle diffusion model suggested significant contribution by film diffusion. The developed low-cost AC could be used to supplement the GA alkaline deactivation process for efficient removal of residual GA aquatic toxicity.

2021 ◽  
Vol 12 (6) ◽  
pp. 8042-8056

In recent years, the presence of pharmaceutical contaminants, such as diclofenac sodium (DCF) in water bodies and their potential influence on aquatic organisms gained much attention. As a result of high demand and usage by consumers, in addition to incomplete removal during wastewater treatment, pharmaceutical contaminants will end up on water surfaces. To mitigate this problem, the elimination of DCF by employing activated carbon derived from Dillenia Indica peels was evaluated. The adsorption of DCF was performed in a continuous process. The findings showed that the adsorption of DCF was favorable at a lower flow rate, greater bed height, and initial DCF concentration, with the highest removal percentage of 44.93%. To assess the characteristics of the breakthrough curve of DCF, the adsorption data were used to match three distinct adsorption models, namely, Boharts and Adam, Yoon-Nelson, and Thomas. The breakthrough results were well-fitted with these models, as the values of R2 for all models and parameters were higher than 0.88. Thus, it was concluded that the activated carbon from Dillenia Indica can effectively remove DCF from an aqueous solution.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 122
Author(s):  
Renwei Lu ◽  
Xiaolong Ren ◽  
Chong Wang ◽  
Changzhen Zhan ◽  
Ding Nan ◽  
...  

Lithium-ion hybrid capacitors (LICs) are regarded as one of the most promising next generation energy storage devices. Commercial activated carbon materials with low cost and excellent cycling stability are widely used as cathode materials for LICs, however, their low energy density remains a significant challenge for the practical applications of LICs. Herein, Na0.76V6O15 nanobelts (NaVO) were prepared and combined with commercial activated carbon YP50D to form hybrid cathode materials. Credit to the synergism of its capacitive effect and diffusion-controlled faradaic effect, NaVO/C hybrid cathode displays both superior cyclability and enhanced capacity. LICs were assembled with the as-prepared NaVO/C hybrid cathode and artificial graphite anode which was pre-lithiated. Furthermore, 10-NaVO/C//AG LIC delivers a high energy density of 118.9 Wh kg−1 at a power density of 220.6 W kg−1 and retains 43.7 Wh kg−1 even at a high power density of 21,793.0 W kg−1. The LIC can also maintain long-term cycling stability with capacitance retention of approximately 70% after 5000 cycles at 1 A g−1. Accordingly, hybrid cathodes composed of commercial activated carbon and a small amount of high energy battery-type materials are expected to be a candidate for low-cost advanced LICs with both high energy density and power density.


Fermentation ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 119
Author(s):  
Vasiliki Summerson ◽  
Claudia Gonzalez Viejo ◽  
Damir D. Torrico ◽  
Alexis Pang ◽  
Sigfredo Fuentes

The incidence and intensity of bushfires is increasing due to climate change, resulting in a greater risk of smoke taint development in wine. In this study, smoke-tainted and non-smoke-tainted wines were subjected to treatments using activated carbon with/without the addition of a cleaving enzyme treatment to hydrolyze glycoconjugates. Chemical measurements and volatile aroma compounds were assessed for each treatment, with the two smoke taint amelioration treatments exhibiting lower mean values for volatile aroma compounds exhibiting positive ‘fruit’ aromas. Furthermore, a low-cost electronic nose (e-nose) was used to assess the wines. A machine learning model based on artificial neural networks (ANN) was developed using the e-nose outputs from the unsmoked control wine, unsmoked wine with activated carbon treatment, unsmoked wine with a cleaving enzyme plus activated carbon treatment, and smoke-tainted control wine samples as inputs to classify the wines according to the smoke taint amelioration treatment. The model displayed a high overall accuracy of 98% in classifying the e-nose readings, illustrating it may be a rapid, cost-effective tool for winemakers to assess the effectiveness of smoke taint amelioration treatment by activated carbon with/without the use of a cleaving enzyme. Furthermore, the use of a cleaving enzyme coupled with activated carbon was found to be effective in ameliorating smoke taint in wine and may help delay the resurgence of smoke aromas in wine following the aging and hydrolysis of glycoconjugates.


RSC Advances ◽  
2016 ◽  
Vol 6 (99) ◽  
pp. 96573-96583 ◽  
Author(s):  
Raja Mohamed Sait Thameem Azarudeen ◽  
Marimuthu Govindarajan ◽  
Abubucker Amsath ◽  
Shine Kadaikunnan ◽  
Naiyf S. Alharbi ◽  
...  

As a low-cost and eco-friendly control tool, Ag nanoparticles were fabricated usingHedyotis puberulaaqueous extract as a reducing and capping agent and showed potent activity against malaria and arbovirus vectors with low biotoxicity against non-target aquatic organisms.


2015 ◽  
Vol 659 ◽  
pp. 304-309
Author(s):  
Khemmakorn Gomonsirisuk ◽  
Thanakorn Wasanapiarnpong

Organic contaminated wastes water from petrochemical industries can be removed by adsorbent and photocatalyst. In this work, the degradation rate of phenol have been studied at different ratios of activated carbon/NaA zeolite composite materials coated with TiO2 photocatalyst which are easily to be fabricated into tubular shape by extrusion method. In addition, the foam-inserted composite can be floated on the surface of waste water for the higher phocatalyst activity. While the composite is the low cost adsorbent with high absorption and high ion exchange properties. In order to optimize the efficiency of material, the various ratios of activated carbon/NaA zeolite (3:1, 1:1 and 1:3) and amount of coated TiO2 on the specimen’s surface was studied by UV/Vis spectrophotometer which related to phenol concentration. Moreover the various amount of phenolic resins (10, 20, 30, 40 and 50 wt%) at different reduction firing temperatures (600 and 650 °C) with soaking time of 1, 2 and 3 hours affected to the compressive strength of samples. For the characterization, XRD is used to characterize the phase and SEM is used to provide the morphology of the prepared composite materials.


2017 ◽  
Vol 51 (18) ◽  
pp. 10913-10922 ◽  
Author(s):  
Leland R. Widger ◽  
Megan Combs ◽  
Amit R. Lohe ◽  
Cameron A. Lippert ◽  
Jesse G. Thompson ◽  
...  

2014 ◽  
Vol 9 (1) ◽  
pp. 166-174 ◽  
Author(s):  
Rajeshwar M. Shrestha ◽  
Margit Varga ◽  
Imre Varga ◽  
Amar P. Yadav ◽  
Bhadra P. Pokharel ◽  
...  

Activated carbons were prepared from Lapsi seed stone by the treatment with H2SO4 and HNO3 for the removal of Ni (II) ions from aqueous solution. Two activated carbon have been prepared from Lapsi seed stones by treating with conc.H2SO4 and a mixture of H2SO4 and HNO3 in the ratio of 1:1 by weight for removal of Ni(II) ions. Chemical characterization of the resultant activated carbons was studied by Fourier Transform Infrared Spectroscopy and Boehm titration which revealed the presence of oxygen containing surface functional groups like carboxyl, lactones and phenols in the carbons. The optimum pH for nickel adsorption is found to be 5. The adsorption data were better fitted with the Langmuir equations than Freundlich adsorption equation to describe the equilibrium isotherms. The maximum adsorption capacity of Ni (II) on the resultant activated carbons was 28.25.8 mg g-1 with H2SO4 and 69.49 mg g-1 with a mixture of H2SO4 and HNO3. The waste material used in the preparation of the activated carbons is inexpensive and readily available. Hence the carbons prepared from Lapsi seed stones can act as potential low cost adsorbents for the removal of Ni (II) from water. DOI: http://dx.doi.org/10.3126/jie.v9i1.10680Journal of the Institute of Engineering, Vol. 9, No. 1, pp. 166–174


1995 ◽  
Vol 22 (1) ◽  
pp. 106-120
Author(s):  
Roberto M. Narbaitz ◽  
Frances Z. Parsons ◽  
Tsong-Yih Tzeng

Point-of-entry systems with granular activated carbon filters have been used extensively to provide safe water to rural homes with wells contaminated with synthetic organic chemicals. Because of the low cost of these systems, their design is generally based on the equilibrium column model, the isotherm data from the literature, and a scale-up factor. This paper analyzes the necessary scale-up factors for point-of-entry adsorbers based on fumigant adsorption data gathered through an extensive literature review. The fumigants evaluated are 1,2-dichloropropane, 1,2-dibromo-3-chloropropane, and ethylene dibromide. It was impossible to thoroughly assess the scale-up factors for 1,2-dichloropropane because of the limited data. Column data for the other two fumigants were sufficient to generate column loading lines, which can be used directly without resorting to scale-up factors. Column data showed that the scale-up factors are greatly affected by competitive adsorption with the naturally occurring background organic matter and by preloading of these organic matter. As these phenomena are not well understood, it is presently impossible to accurately predict the appropriate scale-up factors. A recommended design approach is outlined. Key words: adsorption, activated carbon, fumigants, point-of-entry.


Sign in / Sign up

Export Citation Format

Share Document