Supercritical fluid regeneration of activated carbon loaded with heavy molecular weight organics

Madras, Giridhar; Erkey, Can; Akgerman, Aydin

doi:10.1021/ie00018a022

Cited by 89 publications

(73 citation statements)

References 5 publications

(7 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Supercritical dioxide has been used to regenerate carbon loaded with organic compounds (Model1 et al, 1979;de Filippi et al, 1980;Liou, 1988, 1989a;Madras et al, 1993a) and soil loaded with heavy molecular weight organics (Dooley et al, 1987;Roop et al, 1989;Akgerman et al, 1992;Erkey et al, 1993). Other applications include purification of polymers (McHugh and Krukonis, 1986) and extraction of lignocellulosic material from wood (Li and Kiran, 1987;Goto et al, 1990).…”

Section: Introductionmentioning

confidence: 99%

Modeling of supercritical extraction of organics from solid matrices

et al. 1994

Self Cite

View full text Add to dashboard Cite

The desorption profiles of various organics from soil and activated carbon using dense liquid and supercritical carbon dioxide were modeled. The model accounts for effective diffusion of the organics in the solidpores, axial dispersion in the fluid phase, and external mass transfer to the fluid phase from the particle surface. This model, involving partial differential equations, is solved using the orthogonal collocation on finite elements. The model is able to predict the experimental data quite well without any adjustable parameters. The importance of each parameter depended on the system, although adsorption equilibrium and the effective pore diffusion of the organic were the most significant parameters in all the systems investigated.

show abstract

Section: Introductionmentioning

confidence: 99%

Modeling of supercritical extraction of organics from solid matrices

et al. 1994

Self Cite

View full text Add to dashboard Cite

show abstract

“…Both equations described the general shape of the experimental data quite well, but the Freundlich isotherm provided a superior fit. Previous supercritical adsorption studies have found that both the Langmuir (Tan and Liou 1990) and the Freundlich (Madras et al 1993) isotherm models were capable of describing the supercritical adsorption results. Kander and Paulaitis (1983) and Tomasko et al (1993) have applied the Toth isotherm for the description of the loadings of phenol and 2-chlorophenol, respectively, adsorbed from supercritical CO 2 on to activated carbons.…”

Section: Applications Of Liquid Subcritical and Supercritical Co 2 Amentioning

confidence: 99%

“…six-times more efficient than the use of supercritical CO 2 alone and about two-times more efficient than supercritical CO 2 modified with 10% methanol. Madras et al (1993) applied supercritical CO 2 without any modifier for the desorption of naphthalene, phenanthrene, hexachlorobenzene and pentachlorophenol from the activated carbon they studied (produced by Sigma Chemical Co.). Wright et al (1988) adsorbed 50 ppm samples of chrysene, benzanthrone, 1-nitropyrene, dibenzocarbazole and coronene on activated carbon and subjected 1 g of each sample to Soxhlet extraction with carbon disulphide for 16 h, followed by a second similar extraction using methylene chloride.…”

Section: Applications Of Liquid Subcritical and Supercritical Co 2 Amentioning

confidence: 99%

“…DeFilippi et al (1980), Madras et al (1993) and Tan and Liou (1989b) have used the equilibrium theory to describe supercritical adsorption processes, assuming that the mass-transfer resistances are negligible. The desorption profile is a function of the adsorption equilibrium relationship, being applied to isothermal, fixed-bed, piston flow desorption in this case.…”

Section: Local Equilibrium Theory Of Fixed-bed Desorptionmentioning

confidence: 99%

See 1 more Smart Citation

Regeneration of Adsorbents by the Use of Liquid, Subcritical and Supercritical Carbon Dioxide

Grajek

2000

Adsorption Science & Technology

View full text Add to dashboard Cite

ABSTRACT:The literature concerning the adsorption and desorption of environmental impurities from adsorbents by means of liquid, subcritical and supercritical carbon dioxide and the author's work on the subject have been reviewed. The influence of the adsorption and desorption temperature, the pressure and the density of the extraction solvent, the solubility of the adsorbate in the extraction solvent, the activation energy for adsorbate desorption and the particle size of the adsorbent on the adsorbate desorption efficiency by this method were discussed.

show abstract

“…The regeneration of ACs saturated with inorganic compounds is less usual and co-solvents must be used to efficiently extract these adsorbates [16]. The employment of SCCO 2 has also been studied to regenerate ACs saturated with low-volatile organic compounds, e.g., phenol [17][18][19], pesticides [20], herbicides [21], or insecticides [22]. Phenol is the most common model compound in the field of regeneration of ACs [3]: it is a pollutant frequently found in wastewater and drinking water that remains strongly retained on the carbon surface of ACs.…”

Section: Introductionmentioning

confidence: 99%

Supercritical Regeneration of an Activated Carbon Fiber Exhausted with Phenol

et al. 2018

View full text Add to dashboard Cite

Featured Application: Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory. Abstract:The properties of supercritical CO 2 (SCCO 2 ) and supercritical water (SCW) turn them into fluids with a great ability to remove organic adsorbates retained on solids. These properties were used herein to regenerate an activated carbon fiber (ACF) saturated with a pollutant usually contained in wastewater and drinking water, phenol. Severe regeneration conditions, up to 225 bar and 400 • C, had to be employed in SCCO 2 regeneration to break the strong interaction established between phenol and the ACF. Under suitable conditions (regeneration temperature, time, and pressure, and flow of SCCO 2 ) the adsorption capacity of the exhausted ACF was completely recovered, and even slightly increased. Most of the retained phenol was removed by thermal desorption, but the extra percentage removed by extraction allowed SCCO 2 regeneration to be significantly more efficient than the classical thermal regeneration methods. SCCO 2 regeneration and SCW regeneration were also compared for the first time. The use of SCW slightly improved regeneration, although SCW pressure was thrice SCCO 2 pressure. The pathways that controlled SCW regeneration were also investigated.

show abstract

Supercritical fluid regeneration of activated carbon loaded with heavy molecular weight organics

Cited by 89 publications

References 5 publications

Modeling of supercritical extraction of organics from solid matrices

Modeling of supercritical extraction of organics from solid matrices

Regeneration of Adsorbents by the Use of Liquid, Subcritical and Supercritical Carbon Dioxide

Supercritical Regeneration of an Activated Carbon Fiber Exhausted with Phenol

Contact Info

Product

Resources

About