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Removal of chlorhexidine gluconate in presence of a cationic surfactant using acid functionalized activated carbon: Validation of multicomponent models

[url=https://www.coalactivatedcarbon.com/]coal activated charcoal powder[/url]Commercial antiseptic solutions containing a mixture of antibacterial agents such as, chlorhexidine gluconate, in presence of a cationic surfactant like cetrimide, are commonly used as floor, toilet and kitchen cleaning agents. Although a specific composition may be beneficial for disinfecting human beings, these are toxic to aquatic organisms, the plant biota and useful microorganisms present in soil and in municipal sewer pipes. In this study, functional modification of granular activated carbon (GAC) is carried out with hydrochloric and hydrofluoric acids in order to enhance the adsorption capacity of GAC for simultaneous removal of both chlorhexidine gluconate and cetrimide. Hydrofluoric acid functionalized activated carbon shows highest removal of both cetrimide and chlorhexidine gluconate (maximum adsorption capacitypure component chlorhexidine gluconate =349.0 g/g; maximum adsorption capacitypure component cetrimide =23.0 g/g). Average removal of cetrimide by GAC, FAC-HCl and FAC-HF are 36.64 %, 47.09 % and 75.74 % respectively. Surface charge of modified activated carbons is significantly altered as compared to unmodified GAC which provided an enhanced net available driving potential for the positive cetrimonium ions to reach the surface much faster as compared to the bulky chlorhexidine gluconate molecules. Cetrimide then undergoes pure physical adsorption through pore diffusion. However, chlorhexidine gluconate forms surface complexes with the functional groups as confirmed by the relative quantities of oxygenated surface functional groups and Fourier Transform Infrared (FT-IR) analysis. Intraparticle diffusion and Boyd plots show that film diffusion and not intraparticle diffusion is the rate controlling step.[url=https://www.granular-activated-carbon.com/]granular activated carbon suppliers uk[/url]

Mesoporous high-surface-area activated carbon (MHSA-AC)

Mesoporous high-surface-area activated carbon (MHSA-AC), which has a honeycomb structure, was produced from [url=https://www.activated-carbon-pellets.com/]coconut shell activated carbon pellets[/url]coconut shells by simultaneous chemical and physical activation and used for the rapid adsorption of an anionic dye, namely acid orange 10 (AO10), from water. Owing to its porosity and high Brunauer-Emmett-Teller surface area (2283.91 m2g-1), MHSA-AC is a highly efficient adsorbent. It also has good biocompatibility and is a good immobilization carrier; the grooves on the MHSA-AC surface facilitate immobilization. Here, a new, highly efficient, and environmentally friendly simultaneous adsorption and biodegradation (SAB) process was developed. Highly concentrated AO10 (6000 mg L-1, 20 mL) was removed with an efficiency of 100% (pH = 7, 35 °C) by SAB using cells immobilized on MHSA-AC (500 mg).[url=https://www.coconutactivatedcarbon.com/]coconut husk activated carbon[/url] The immobilized cells were used directly, without pretreatment; the SAB process is therefore simple and has good potential for application in the treatment of dyes in industrial wastewater.

The performance of a supercapacitor (SCs) fabricated from coal-based activated carbon was studied in terms of its specific capacitance (C), life cycle and rate performance. In this work, a low cost modified nitrogen-doped coal-based activated carbon (MACN

The performance of a supercapacitor (SCs) fabricated from [url=https://www.coalactivatedcarbon.com/]www.coalactivatedcarbon.com[/url]coal-based activated carbon was studied in terms of its specific capacitance (C), life cycle and rate performance. In this work, a low cost modified nitrogen-doped coal-based activated carbon (MACN) was prepared by KOH/H2O co-activation from lignite. Experimental results and density functional theory (DFT) calculations showed that introducing nitrogen atoms into the coal-based activated carbon leads to a rearrangement of the carbon skeleton structure and changes the surface chemical environment. Leading to the MACN internal disorder increases (ID/IG is up to 0.99), structural stability improves (TGA curves shift right), and various nitrogen functional groups (N-5, N-6, N-Q) are formed on the carbon surface. In addition, the MACN possesses high specific surface area (SBET: 2129 m2/g), abundant micropores (Vmic: 0.62 cm3/g), appropriate mesopores (Vmes: 0.39 cm3/g, Vmes ratio: 38.6%), low impurity content, and highly N-doping (9.59 wt%). These characteristics of the MACN provide for a high C of 323 F/g at a current density of 0.5 A/g. The enhanced MACN is 64.8% higher than the undoped MAC.[url=https://www.granular-activated-carbon.com/]wholesale activated carbon[/url] Furthermore, a high energy density of 10 Wh/kg can be achieved with a MACN-assembled symmetrical cell when the power density of 250 W/kg in 6 M KOH.

Physical and chemical properties and adsorption type of activated carbon

[url=https://www.wyactivatedcarbon.com/products/granular-activated-carbon/activated-carbon-gold-extraction.html]activated carbon extracting gold[/url]Activated carbon was prepared from plum kernels by NaOH activation at six different NaOH/char ratios. The physical properties including the BET surface area, the total pore volume, the micropore ratio, the pore diameter, the burn-off, and the scanning electron microscope (SEM) observation as well as the chemical properties, namely elemental analysis and temperature programmed desorption (TPD), were measured. The results revealed a two-stage activation process: stage 1 activated carbons were obtained at NaOH/char ratios of 0-1, surface pyrolysis being the main reaction; stage 2 activated carbons were obtained at NaOH/char ratios of 2-4, etching and swelling being the main reactions. The physical properties of stage 2 activated carbons were similar, and specific area was from 1478 to 1887m(2)g(-1). The results of reaction mechanism of NaOH activation revealed that it was apparently because of the loss ratio of elements C, H, and O in the activated carbon, and the variations in the surface functional groups and the physical properties. The adsorption of the above activated carbons on phenol and three kinds of dyes (MB, BB1, and AB74) were used for an isotherm equilibrium adsorption study. The data fitted the Langmuir isotherm equation. Various kinds of adsorbents showed different adsorption types; separation factor (R(L)) was used to determine the level of favorability of the adsorption type. In this work, activated carbons prepared by NaOH activation were evaluated in terms of their physical properties, chemical properties, and adsorption type; [url=https://www.wyactivatedcarbon.com/]activated carbon supplier[/url]and activated carbon PKN2 was found to have most application potential.

Ni-doped activated carbon nanofibers for storing hydrogen at ambient temperature: Experiments and computations

[url=https://www.wyactivatedcarbon.com/products/granular-activated-carbon/activated-carbon-gold-extraction.html]activated carbon extracting gold[/url]Activated carbon nanofibers (ACNF*) prepared by carbonization and chemical activation of polyacrylonitrile (PAN)-polyvinylpyrrolidone (PVP) electrospun nanofibers and doped with 5–20 wt% Ni are proposed for hydrogen adsorption at 25 °C. The best hydrogen adsorption capacities up to 2.12 wt% H2 (p(H2) = 100 bar) together with cycling stability upon 10 ad/desorption cycles with average capacity of 1.17 wt% H2 (p(H2) = 50 bar) are obtained from 5 wt% Ni-doped ACNF*. Excellent ad/desorption and reversibility are benefited from small particle sizes (5–10 nm) and uniform distribution of Ni nanoparticles. The latter is due to not only suitable Ni loading content (5 wt%) but also strong interaction between Ni nanoparticles and N atoms in ACNF*, confirmed by both experiments and first-principles computations. Both experiments and computations indicate that hydrogen adsorption mechanisms are not only chemisorption of adsorbed hydrogen atoms onto Ni nanoparticles but also physisorption and spillover of hydrogen[url=https://www.wyactivatedcarbon.com/]activated carbon supplier[/url]

Batch adsorption of phenol onto physiochemical-activated coconut shell

The liquid-phase adsorption of phenol onto coconut shell-based activated carbon, CS850A was investigated for its equilibrium studies and kinetic modeling.[url=https://www.coconutactivatedcarbon.com/]coconut husk activated carbon[/url]Coconut shell was converted into high quality activated carbon through physiochemical activation at 850 degrees C under the influence of CO(2) flow. Beforehand, the coconut shell was carbonized at 700 degrees C and the resulted char was impregnated with KOH at 1:1 weight ratio. In order to evaluate the performance of CS850A, a series of batch adsorption experiments were conducted with initial phenol concentrations ranging from 100 to 500 mg l(-1), adsorbent loading of 0.2g and the adsorption process was maintained at 30+/-1 degrees C. The adsorption isotherms were in conformation to both Langmuir and Freundlich isotherm models. Chemical reaction was found to be a rate-controlling parameter to this phenol-CS850A batch adsorption system due to strong agreement with the pseudo-second-order kinetic model.[url=https://www.activated-carbon-pellets.com/]coconut shell activated carbon pellets[/url] Adsorption capacity for CS850A was found to be 205.8 mg g(-1).

Simultaneous catalytic hydrolysis of HCN, COS and CS2 over metal-modified microwave coal-based activated carbon

In this work, a series of metal oxides modified microwave coal-based activated carbon[url=https://www.coalactivatedcarbon.com/]www.coalactivatedcarbon.com[/url] (MCAC) catalysts were prepared for simultaneously catalytic hydrolysis of hydrogen cyanide (HCN), carbonyl sulfide (COS) and carbon disulfide (CS2). The influences of metal species, precursor, metal oxides amount and calcination temperature were investigated. The interaction between Al2O3 and MCAC improved the dispersion of Al and enhanced the removal efficiency of catalyst. Al2O3 was the main active component and it provided the adsorption and hydrolysis abilities. The alkaline and strong oxidation sites were responsible for removing HCN, COS and CS2. Meanwhile, the adsorbed water was beneficial to the catalytic hydrolysis reactions. Al2O3 was attributed to the decomposition of aluminum salt. Under excessive high calcination temperature, Al2O3 reacted with surface functional groups.[url=https://www.granular-activated-carbon.com/]wholesale activated carbon[/url] The formation of Al2(SO4)3 and Al(NO3)3 resulted in the deactivation of catalyst.

The coconut shell activated carbon (CSAC) prepared using KOH

Adsorptive removal of parachlorophenol (PCP) and 2,4,6-trichlorophenol (TCP) from aqueous solutions by activated carbon prepared from coconut shell was studied and compared with activated carbon of commercial grade (CAC). Various chemical agents in different concentrations were used (KOH, NaOH, CaCO(3), H(3)PO(4) and ZnCl(2)) for the preparation of coconut shell activated carbon. The coconut shell activated carbon[url=https://www.coconutactivatedcarbon.com/]coconut carbon[/url](CSAC) prepared using KOH as chemical agent showed high surface area and best adsorption capacity and was chosen for further studies. Batch adsorption studies were conducted to evaluate the effect of various parameters such as pH, adsorbent dose, contact time and initial PCP and TCP concentration. Adsorption equilibrium reached earlier for CSAC than CAC for both PCP and TCP concentrations. Under optimized conditions the prepared activated carbon showed 99.9% and 99.8% removal efficiency for PCP and TCP, respectively, where as the commercially activated carbon had 97.7% and 95.5% removal for PCP and TCP, respectively, for a solution concentration of 50mg/L. Adsorption followed pseudo-second-order kinetics. The equilibrium adsorption data were analysed by Langmuir, Freundlich, Redlich-Peterson and Sips model using non-linear regression technique. Freundlich isotherms best fitted the data for adsorption equilibrium for both the compounds (PCP and TCP). Similarly, acidic pH was favorable for the adsorption of both PCP and TCP. Studies on pH effect and desorption revealed that chemisorption was involved in the adsorption process. The efficiency of the activated carbon prepared was also tested with real pulp and paper mill effluent. [url=https://www.activated-carbon-pellets.com/]bulk activated carbon[/url]The removal efficiency using both the carbons were found highly satisfactory and was about 98.7% and 96.9% as phenol removal and 97.9% and 93.5% as AOX using CSAC and CAC, respectively.

Effect of granular activated carbon pore-size distribution on biological activated carbon filter performance

Proper granular activated carbon (GAC[url=https://www.granular-activated-carbon.com/]granular carbon[/url]selection could improve the performance of biological activated carbon (BAC) filters through a combination of adsorption and biodegradation, while the GACs used in BAC filters are now mainly selected according to adsorption function, ignoring biodegradation. In this study, sand filter effluent obtained from a drinking water treatment plant was fed into continuous-flow bench-scale BAC columns operated in parallel over 245 days to examine the effects of GAC pore-size distribution on BAC filter performance, in terms of the dissolved organic carbon (DOC) and disinfection byproduct (DBP) precursors. A metagenomic analysis indicated that bacterial community structure played an important role in BAC filter performance. A significant correlation was found between metabolism-related proteins and the volume of micro-level macropores based on metaproteomic analysis. It is suggested that the adsorption saturation was dynamic and that adsorption played a role in the performance of the BAC filters throughout the 245-day operating period. Renewed adsorption capacity, or bioregeneration, was driven by bacterial metabolic activity. Such activity largely depended on the organic matter adsorbed by the GAC, in which micro-level macropores, especially those with diameters of 0.2–10 μm, played an important but previously unrecognized role.[url=https://www.coalactivatedcarbon.com/]coal carbon manufacturer[/url] The results suggest that more attention should be paid to well-developed pores and pore-size distribution in the production and selection of GAC used for full-scale drinking water biofilters.

Activated carbons prepared by indirect and direct CO2 activation of lignocellulosic biomass for supercapacitor electrodes

Lignocellulosic biomass was converted into hierarchical porous carbon by using a physical activation technique under a carbon dioxide environment.[url=https://www.wyactivatedcarbon.com/]https://www.wyactivatedcarbon.com[/url] Both direct and indirect CO2 activation routes were utilized to investigate the effect of processing parameters and the kinetics of the activation. The porosity, surface chemistry, and morphology of the activated carbons were characterized in addition to their proximate and ultimate analyses. This was followed by the preparation of the activated carbon electrodes and the fabrication and electrochemical testing of these electrodes within a symmetrical supercapacitor cell. The results showed a dominant microporous structure along with the limited content of larger pores for the activated carbons prepared via both direct and indirect activation. Along with the preserved natural pore structure of the biomass, an engineered pore structure was achieved which is highly beneficial for the supercapacitors with respect to the transport and storage of ions. The morphological analysis also revealed their tortuous porous structure. The maximum specific capacitances of 80.9 and 92.7 F/g at the current density of 100 mA/g were achieved after direct and indirect activation routes, respectively. The surface functional groups were also found to play a significant role in the resultant electrochemical performance of the supercapacitors.[url=https://www.wyactivatedcarbon.com/products/granular-activated-carbon/activated-carbon-gold-extraction.html]activated carbon gold recovery[/url]


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