Sorption recovery

Figure 12 Schematic diagram of module for sorption recovery of uranium using energy of waves for propogation of seawater through the sorbent bed.

Svanidze, A. G. Technological Schemes and Devices for Sorption Recovery of Microelements from Sea Water, Deponent VINITI USSR No. 8030-B85, Moscow, 1986. 

Inagaki, M., Kawahara, A., and Hayashi, T. (2001). Sorption, recovery and recycling of heavy oil by using carbonized fir fiben. Res. Rep. Aichi Inst. Technol, 36, 69-78 (in Japanese). 

Inagaki, M., Toyoda, M., Iwashita, N., et al. (2002). Sorption, recovery and recycle of spiUed heavy oils using carbon materials. TANSO, 16—25 (in Japanese). 

Sarkar, A.R., Datta, P.K., and Sarkar, M., Sorption recovery of metal ions using silica gel modified with salicylaldoxime, Talanta, 43, 1857, 1996. 

Keywords Exfoliated graphite, heavy oil, sorption, recovery, recycling... 

In January 1997, the oil tanker Nakhodka spilled almost 4.5 x 10 tons of oil near the coast of Japan Sea. This accident had a strong impact because the spilled oil moved along the coastline, extending over some 250 km, and it seriously contaminated the shoreline [3]. Actually, this particular tanker accident motivated the present series of investigations, that is, sorption, recovery, and recycling of spilled heavy oils using macroporous carbon materials. 

Multiple additions of phenolic acids were used because phenolic acid concentrations in soil decline rapidly after each addition of phenolic acids (Blum et al. 1987 Blum and Gerig 2006). This was due to microbial metabolism, physical breakdown, root uptake, and/or soil particle sorption. Recovery of seedling processes, although considerably slower than in nutrient culture, also occurred in seedling-soil systems (Blum et al. 1987 Blum and Gerig 2006). To maintain inhibition for extended time periods multiple additions of phenolic acids were required. 

To improve the rheological properties and extend the very short working time, a simple polyester is kicluded as thinner. Mixing is easy, and dimensional change ki ak is less than 0.1% over several hours. Elastic recovery and reproduction of detail are exceUent. The elastomeric cycHc imine impression materials have a higher modulus of elasticity than the condensation siHcone or polysulfide mbbers, and are more difficult to remove from the mouth. The materials have relatively low tear strength and an equUibrium water sorption of 14% thus, polyether impression materials tear readily. Because of thek poor dimensional stabUity ki water, they should be stored ki a dry environment. 

Two techniques for sorption-spectroscopic determination of ascorbic acid have been proposed. The first one is the recovery by silica modified with tetradecyl ammonium nitrate of blue form of molibdophosphoric HPA in the presence of vitamin C. And the second one is the interaction between the ascorbic acid in solution and immobilized on silica ion associate of molibdophosphoric acid with lucigenine. The detection limits of vitamin C are 0.07 and 2.6 mg respectively. The techniques were successfully applied to the determination of ascorbic acid in fmit juices. 

The capacity factors of SN-SiO, for metal ions were determined under a range of different conditions of pH, metal ions concentrations and time of interaction. Preconcentration of Cd ", Pb ", Zn " and CvS were used for their preliminary determination by flame atomic absorption spectroscopy. The optimum pH values for quantitative soi ption ai e 5.8, 6.2, 6.5, 7.0 for Pb, Cu, Cd and Zn, respectively. The sorption ability of SN-SiO, to metal ions decrease in line Pb>Cu> >Zn>Cd. The soi ption capacity of the sorbent is 2.7,7.19,11.12,28.49 mg-g Hor Cd, Zn, Pb, andCu, respectively. The sorbent distribution coefficient calculated from soi ption isotherms was 10 ml-g for studied cations. All these metal ions can be desorbed with 5 ml of O.lmole-k HCl (sorbent recovery average out 96-100%). 

The application of open sorption systems can provide dehumidification by the adsorption of water vapor and sensible cooling by adiabatic humidification (after a cold recovery for the dried air) at temperatures between 16 °C and 18 °C. Conventional systems have to reach temperature as low as 6 °C or lower in order to start dehumidification by condensation. For comfort reasons this cold air has to be heated up to about 18 °C before released into the building. This shows that open sorption systems can provide in general an energetically preferable solution. 

U.S. EPA defines MNA as the reliance on natural processes, within the context of a carefully controlled and monitored site cleanup approach, to achieve site-specific remediation objectives within a time frame that is reasonable compared to that offered by other more active methods. The natural processes include biodegradation, dispersion, dilution, sorption, volatilization, stabilization, and transformation. These processes reduce site risk by transforming contaminants to less toxic forms, reducing contaminant concentrations, and reducing contaminant mobility and bioavailability. Other terms for natural attenuation in the literature include intrinsic remediation, intrinsic bio-remediation, passive bioremediation natural recovery, and natural assimilation. 30... 

SH Gehrke, NR Vaid, JF McBride. Protein sorption and recovery by hydrogels using principles of two aqueous phase protein extraction. Biotech Bioeng 58 416-427, 1998. 

Navarro, R., Guzman, J., Saucedo, I., Revilla, J. and Guibal, E. (2003) Recovery of metal ions by chitosan sorption mechanisms and influence of metal speciation. Macromolecular Bioscience,... 

Selective ad(b)sorption of compounds from wastewater, focused on recovery... 

Hysteresis is observed not only in the sorption isotherms but also in calorimetric measurements of heat of wetting at different moisture contents, and it is thus a combined entropy and enthalpy phenomenon. A reliable explanation for this effect is not currently available, but there is speculation that it is due to the stresses which are induced as the cellulose swells. Since the swelling of cellulose is not completely reversible, mechanical recovery is incomplete and hysteresis will therefore be present both in the internal stress-strain curve of the sample, and also in the water adsorption isotherm. 

Brown, C.J. (1999) Mixed acid recovery with the APU acid sorption system - an update. Paper presented at the Cleaner Production Workshop, China Steel Corporation, Kaohsiung, Taiwan. 

The reversibility of sorption has considerable environmental relevance, because it permits the recovery of ecosystems after exposure to contamination, and makes possible the re-dissolution of chemicals that have been sorbed onto particulate material. For this reason, this aspect has been studied extensively, with results showing that sorption onto natural sediments is a reversible process for non-ionic [17] and anionic surfactants [8,20,30,45,46]. This desorption process, however, has not been confirmed by other authors [3,14]. 

Sorption. Any reduction in analyte recovery in the presence of solid media may be a reflection of losses through sorption or actual degradation, and in reality it is difficult to quantify degradation due to the unknown extent of the sorption processes. Sorption can be by intercalation (absorption), and/or electrostatic attraction and covalent... 

The results indicate that persistence of organosilicone surfactants in the parent molecule form will be limited on typical soil media and in aqueous environments. Reduced recovery was considered to be a result of abiotic degradation and/or strong sorption processes. Losses were most significant on solid media exhibiting extreme pH values and were also enhanced in the presence of clay substrates. Studies on clays indicated that pH, potential for intercalation and surface charges are important factors in the removal process. 

Surfactants are selected based primarily on the degree of solubilization. Other factors to be considered include toxicity, biodegradability, surfactant sorption, and surfactant solubility and compatibility with the separation process. Surfactants have the ability to lower the interfacial tension between water and the contaminant by as little as a factor of three to four orders of magnitude. Combined with a sufficient reduction in capillary forces, this allows pumped groundwater theoretically to move the DNAPL toward the recovery or extraction well. This is accomplished by injecting surfactant solution into the contaminated zone. Impacted groundwater characterized by an increase in the concentration of the contaminant is then recovered and treated. 

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