Adsorption of volatile organic compounds on soil and prediction of desorption breakthroughs

1997-01-01
Yeo, SD
Tuncer, E
Akgerman, A
Vapor extraction of volatile organic compounds from soil was investigated by performing adsorption and desorption experiments of trichloroethylene, trichloroethane, and chlorobenzene on soil particles. The adsorption breakthrough curves were obtained using a dynamic response technique based on frontal analysis chromatography. The shape of the breakthrough curves indicated that the adsorption process was close to an ideal adsorption system of no mass transfer resistance, no axial dispersion, and infinitesimal width of mass transfer zone. The adsorption isotherms were BET Type I for trichloroethylene and trichloroethane, and BET Type II for chlorobenzene. Two types of desorption profiles were observed depending on the compounds, i.e., the continuously decreasing profiles of trichloroethylene and trichloroethane and the stepwise decreasing profiles of chlorobenzene. The desorption profiles of trichloroethylene and trichloroethane were simulated using a local equilibrium theory which indicated that desorption behavior was independent of the number of adsorption layers on soil. For chlorobenzene, the monolayer desorption was the rate-controlling step of the overall desorption process. The effect of moisture on desorption efficiency was significant for chlorobenzene, which showed more unfavorable desorption behavior than trichloroethylene and trichloroethane.
SEPARATION SCIENCE AND TECHNOLOGY

Suggestions

Phase transition of chemically synthesized FePt nanoparticles under high pressure
ŞİMŞEK, TELEM; Karci, Ozgur; ÖZCAN, ŞADAN (The Scientific and Technological Research Council of Turkey, 2018-01-01)
We present the results of a study related to phase transformation of chemically synthesized FePt nanoparticles under high pressure from face-centered cubic into face-centered tetragonal structure. As-synthesized nanoparticles are around 4.5 nm and show superparamagnetic behavior at 300 K. After annealing under 60 bar pressure of hydrogen at 400 degrees C for 2 h, nanoparticles exhibit strong ferromagnetic behavior with 5391 Oe coercivity. Results show that high-pressure annealing lowers the decomposition te...
Vulcan-Supported Pt Electrocatalysts for PEMFCs Prepared using Supercritical Carbon Dioxide Deposition
Bayrakceken, Ayse; Smirnova, Alevtina; Kitkamthorn, Usanee; Aindow, Mark; Tuerker, Lemi; Eroğlu, İnci; ERKEY, CAN (Informa UK Limited, 2009-01-01)
In this study, supercritical carbon dioxide (scCO(2)) deposition was used to prepare vulcan-supported Pt (Pt/Vulcan) electrocatalysts for proton exchange membrane fuel cells (PEMFCs), and the effects of process variables on the properties of the electrocatalysts were investigated. The two different methods used to reduce the organometallic precursor were thermal reduction in nitrogen at atmospheric pressure and thermal reduction in scCO(2). In the former method, the maximum Pt loading achieved was 9%, and t...
Experimental investigation of drag reduction effects of polymer additives on turbulent pipe flow using ultrasound Doppler velocimetry
Zeybek Vural, Serife; Bayram, Göknur; Uludağ, Yusuf (The Scientific and Technological Research Council of Turkey, 2014-01-01)
Drag reduction in fully developed turbulent pipe flow with 4 concentrations (200 to 500 wppm or mg/kg) of low molecular weight sodium carboxymethylcellulose (CMC) in aqueous solutions was investigated experimentally. Drag reduction was determined by pressure drop measurements. Maximum drag reduction achieved was 22% using 500 wppm CMC solution. To observe the impact of the presence of CMC on the flow, ultrasound Doppler velocimetry (UDV) was employed to monitor the instantaneous velocity distributions. Expe...
Nanofiltration and Reverse Osmosis for Reuse of Indigo Dye Rinsing Waters
Uzal, Nigmet; Yılmaz, Levent; Yetiş, Ülkü (Informa UK Limited, 2010-01-01)
A membrane based treatment strategy was developed for the possible recycling of rinsing wastewater from indigo dyeing to the process itself. Performances of three different nanofiltration (NF) (NF 270 and NF 90, Dow Film Tech, USA and NF 99, Alfa Laval, Denmark) and two different reverse osmosis (RO) (HR 98 PP and CA 995 PE, Alfa Laval, Denmark) membranes were investigated with wastewater collected from the first post-rinsing tank of indigo dyeing process of a denim manufacturing plant. Dead-end microfiltra...
Adsorption of dithiophosphate and dithiophosphinate on chalcopyrite
Guler, T; Hicyilmaz, C; Gokagac, G; Ekmeci, Z (Elsevier BV, 2006-01-01)
Electrochemical behavior of chalcopyrite was investigated in the absence and presence of dithiophosphate (DTP) and dithiophosphinate (DTPI), selective thiols against Fe-sulfides in the flotation of sulfide ores, in potentiostatically controlled electrochemical condition. Diffuse reflectance Fourier transformation (DRIFT) spectroscopy was applied to determine the type of adsorbed collector species, and Hallimond tube flotation tests were performed to clarify the role of polarization potential and thiol colle...
Citation Formats
S. Yeo, E. Tuncer, and A. Akgerman, “Adsorption of volatile organic compounds on soil and prediction of desorption breakthroughs,” SEPARATION SCIENCE AND TECHNOLOGY, pp. 2497–2512, 1997, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66484.