Sorbent applications

The number of publications involved with the recovery of rubidium from seawater is very limited. Most of the work in this field is by Russian scientists, who have proposed several schemes for the combined recovery of rubidium, strontium, and potassium with natural zeolites [15, 19, 250-253, 257]. A number of inorganic sorbents with high selectivity toward rubidium were also synthesized for the recovery of rubidium from natural hydromineral sources, including seawater. Ferrocyanides of the transition-metal ions were shown to exhibit the best properties for this purpose [258, 259]. Mordenite (another natural zeolite) has recently been proposed for selective recovery of rubidium from natural hydromineral sources as well [260]. A review of the properties of inorganic sorbents applicable for the recovery of rubidium from hydromineral sources has been published [261]. Studies of rubidium recovery fix>m seawater [15, 19, 250-253] have shown that the final processing of rubidium concentrates, especially the selective separation of Rb -K mixtures remains the major problem. A report was recently published showing that this problem can be successfully solved by countercurrent ion exchange on phenolic resins [262]. 

Filter discs (free and in syringes) reversed phase, normal phase, ion-exchange, and mixed-mode sorbents application examples available... 

Tests are presently underway to use jute and kenaf sorbents to remove heavy metals, pesticides, and oil from rain water run off in several cities in the United States. Medium-and high-density mats can also be used for oil spill clean up pillows. It has been shown that the core material from kenaf preferentially sorbs oil out of seawater when saturated with water. There are many other potential sorbent applications of agrofiber and core resources such as removal of dyes, trace chemicals in solvents, and in the purification of solvents. 

This chapter deals with the advancements in enhanced fuel conversion by sorbents. Particular attention will be devoted to sorbent application in power plants for H2 production and/or CO2 capture using both natural gas and coal as feedstock. 

Kocjan, R. Przeszlakowski, S. Calcon-modified sihca gel sorbent. Application to preconcentration or elimination of trace metals. Talanta 1992, 39 (1), 63-68. 

L., and Voilley, A. (1998) Trapping of gamma-decalactone by adsorption on hydrophobic sorbents application to the bioconversion of methyl ricinoleate by the yeast Sporidiobolus salmonicolor. Biotechnol. Tech., 12, 109-113. 

Although there are many practical applications for which the sorbent is discarded after one use, most applications of interest to chemical engineers involve the removal of adsorbates from the sorbent (i.e., regeneration). This allows the adsorbent to be reused and the adsorbates to be recovered. 

Application of a modified sorbent is preferable, since in this case the intensity luminescence (/) of Ln, as well as the rate of its determination is higher about 6-7 times. The comparison of luminescence intensity of Ln -ligand complex solution before the soi ption with results of I after soi ption by both non-modified and modified PMMA showed that I increased in 30 and about 200 times, respectively. 

Having wide and increasing quantity of RP HPLC sorbents in disposal the main question in RP HPLC is their interchangeability. Column chai acteristics that ai e usually described by their manufacturers are not full enough for the analytic to choose a suitable column for the specified resolutions or he ought to choose other similar column used before. In fact, nomenclature of reversed-phase stationai y phases is too unsophisticated and is a source of confusion in their application. 

The opportunity of application of filters, solid sorbents and absorbing solutions has been investigated for synthetic pyrethroids concentrating from air. Silicagel KSK and polysorb are provided quantitative sorbption and desorbption pyrethroids. In case of aerosol formulations application of paper filters is possible. 

Theoretical and applied aspects of microwave heating, as well as the advantages of its application are discussed for the individual analytical processes and also for the sample preparation procedures. Special attention is paid to the various preconcentration techniques, in part, sorption and extraction. Improvement of microwave-assisted solution preconcentration is shown on the example of separation of noble metals from matrix components by complexing sorbents. Advantages of microwave-assisted extraction and principles of choice of appropriate solvent are considered for the extraction of organic contaminants from solutions and solid samples by alcohols and room-temperature ionic liquids (RTILs). 

Thus, possibility of application of Cartridges Packed DIAPAK for concentrating different antibiotics and analyzing them by RP HPLC was shown. Maximum sorbated quantity of Cefazoline is 1.2 tg on 1 g sorbent. 

Volume 46 Zeolires as Catalysts, Sorbents and Detergent Builders. Applications and... 

Desorption The removal of adsorbed materials from a solid sorbent by the use of a solvent or the application of heat. Desulfurization The removal of sulfur from flue or other sulfur-containing gases. 

Size exclusion chromatography (SEC, also known as GPC and GFC) has become a very well accepted separation method since its introduction in the late-1950s by works of Porath and Flodin (1) and Moore (2). Polymers Standards Service (PSS) packings for SEC/SEC columns share this long-standing tradition as universal and stable sorbents for all types of polymer applications. In general, PSS SEC columns are filled with spherical, macroporous cross-linked, pressure-stable, and pH-resistant polymeric gels. 

Table 9.3 also shows that there have been some improvements in SEC sorbents for aqueous applications since the early 1990s with the availability of PSS HEMA and PSS SUPREMA columns. Table 9.4 gives an overview of available packings and their major use (this table is not complete and is intended for showing the major features and uses in SEC applications). 

Projects in the CCT program demonstrated innovative applications for both wet and dry or seniidry FGD systems. The wet FGD systems, which use limestone as an absorber, have met or exceeded the 90 percent SO, removal efficiency required to meet air quality standards when burning high-sulfur coal. The di"y or semidry systems use lime and recycled fly ash as a sorbent to achieve the required removal. 

We believe that better understanding of the behavior of macromolecules at the solid surfaces will facilitate further progress in chemical design of the composite sorbents as well as other bioseparation media such as membranes, fibers etc. and their application in various fields. 

The consideration made above allows us to predict good chromatographic properties of the bonded phases composed of the adsorbed macromolecules. On the one hand, steric repulsion of the macromolecular solute by the loops and tails of the modifying polymer ensures the suppressed nonspecific adsorptivity of a carrier. On the other hand, the extended structure of the bonded phase may improve the adaptivity of the grafted functions and facilitate thereby the complex formation between the adsorbent and solute. The examples listed below illustrate the applicability of the composite sorbents to the different modes of liquid chromatography of biopolymers. 

For chromatographic sorbents it is necessary that the polymeric cover be uniformly distributed over the silica surface and chemically coupled to it. The appropriate introduction of the initiator is one of the decisive steps of this task. The first method (binding to the surface) increases the yield of grafted polymer. However in this case a large amount of homopolymer is formed. This disadvantage could be prevented by the application of hydroperoxide initiators in combination with the proper redox-agents [78-81],... 

The above results prove the potential of the graft polymerization technique for the preparation of composite sorbents. The next section will be devoted to the application of such materials in the chromatography of biopolymers. 

Recently, new approaches of sorbent construction for reversed-phase chromatography have been developed. Silicas modified with hydrocarbon chains have been investigated the most and broadly utilized for these aims. Silica-based materials possess sufficient stability only in the pH 2-8 range. Polymeric HPLC sorbents remove these limitations. Tweeten et al. [108] demonstrated the application of stroongly crosslinked styrene-divinylbenzene resins for reversed-phase chromatography of peptides. 

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