Removal of Lead ions

Zhu, X., Jyo, A., Column-mode removal of lead ion with macroreticular glycidyl methacrylate-divinylbenzene copolymer-based phosphoric acid resins, J. Ion Exchange 11, 2000,68-77. 

Entezari, M.H. and T.R. Bastami. 2006. Sono-sorption as a new method for the removal of lead ion from aqueous solution. J. Hazard. Mater B 137 959-964. 

Makhloufi L, Saidani B, Hammache H. Removal of lead ions from acidic aqueous solutions by cementation on iron. Water Res 2000 34 2517-2524. 

Hajdu, I., Bodnar, M., Csikos, Z., Wei, S., Daroczi, L., Kovacs, B., Gyori, Z., Tamas, J. Borbely, J. (2012) Combined nano-membrane technology for removal of lead ions. Journal of Membrane Science, 409,44-53. 

THE PHOTOCATALYSED REMOVAL OF LEAD IONS FROM SOLUTION When the photocatalyst anatase is suspended in lead(Il) acetate solution and the suspension is irradiated by a u.v. source, it is expected that the photoexcited electrons in the conduction band of the catalyst would reduce lead ions in solution, whereas the holes generated in the valence band would react at the surface forming OH radicals. These are likely to oxidise the acetate ions to CO2. 

Scott, J., Guang, D., Naeramitmamsuk, K., Thabuot, M., Amal, R. Zeolite synthesis liom coal fly ash for the removal of lead ions from aqueous solution. J. Chem. TechnoL BiotechnoL 77, 63-69 (2001)... 

Scott et al. [18] have established that the synthesized fly ash zeolites can be a suitable material for the removal of lead ions from aqueous solution within 24 h of application. They have reported that type of zeolites (viz., zeolites X, Na-Pl, Sodalite and Phillipsite) synthesized in the hydrothermal method can depend on the treatment time, concentration of NaOH solution and the type of fly ash employed in the process. It has been concluded that the type of zeolites and their morphology can influence the rate of lead ion removal. 

Leading Examples Electrodialysis has its greatest use in removing salts from brackish water, where feed salinity is around 0.05-0.5 percent. For producing high-purity water, ED can economically reduce solute levels to extremely low levels as a hybrid process in combination with an ion-exchange bed. ED is not economical for the produc tion of potable water from seawater. Paradoxically, it is also used for the concentration of seawater from 3.5 to 20 percent salt. The concentration of monovalent ions and selective removal of divalent ions from seawater uses special membranes. This process is unique to Japan, where by law it is used to produce essentially all of its domestic table salt. ED is very widely used for deashing whey, where the desalted product is a useful food additive, especially for baby food. 

Ion exchange resins are also useful for demineralising biochemical preparations such as proteins. Removal of metal ions from protein solutions using polystyrene-based resins, however, may lead to protein denaturation. This difficulty may be avoided by using a weakly acidic cation exchanger such as Bio-Rex 70. 

Chemical precipitation is used in porcelain enameling to precipitate dissolved metals and phosphates. Chemical precipitation can be utilized to permit removal of metal ions such as iron, lead, tin, copper, zinc, cadmium, aluminum, mercury, manganese, cobalt, antimony, arsenic, beryllium, molybdenum, and trivalent chromium. Removal efficiency can approach 100% for the reduction of heavy metal ions. Porcelain enameling plants commonly use lime, caustic, and carbonate for chemical precipitation and pH adjustment. Coagulants used in the industry include alum, ferric chloride, ferric sulfate, and polymers.10-12... 

At the O/S interface, for each molecule of alumina formed inside the oxide layer, i.e., three O2- ions transferred across the O/S interface, six hydrogen ions are formed. Thus, the acidity at the interface tends to rise to an extent which depends on the rate removal of these ions by some mechanism. In view of Eqs. (13) to (15), this should lead to oxide dissolution and a further decrease... 

Of special interest was the removal of lead. Most lead was removed during the loading and first washing cycle, which indicates lead is being complexed by the chloride ion. This complex is currently being used to aid in the decontamination of lead in the oxalate precipitation process. 

MALDI is relatively less sensitive to contamination by salts, buffers, detergents, and so on in comparison with other ionization techniques [41], The analyte must be incorporated into the matrix crystals. This process may generally serve to separate in solid phase the analyte from contaminants. However, high concentrations of buffers and other contaminants commonly found in analyte solutions can interfere with the desorption and ionization process of samples. Prior purification to remove the contaminants leads to improvements in the quality of mass spectra. For instance, the removal of alkali ions has proven to be very important for achieving high desorption efficiency and mass resolution. 

Removal of free ions occurs by two mechanisms ion-ion recombination (essentially saturated ternary ion-ion recombination effective binary coefficient a = 2 10 cm s ) and ion-attachment to aerosol particles. The latter process leads to so-called large ions which are, in fact, electrically-charged aerosols rather than ions in a strictly physical sense [60]. Usually, ion-attachment is the most important sink for free ions throughout the troposphere as the tropospheric aerosol content is relatively large (Fig. 2). In this respect, the tropospheric ionization-deionization balance differs greatly from the stratospheric one. 

MEK, 2-butanone, methyl ethyl ketone MEMO, 2-methoxyethoxymethylchloride Mercurochrome, mercury dibromofluorescein MES, 2-(7V-morpholino)-ethanesulfonic acid MESNA, Na 2-mercaptoethanesulfonate Metal impurities, by complexation by ion exchange resins by precipitation removal by extraction removal from reagents removal of lead removal of iron Methylarenes... 

Srivastava S.K., R, Tyagi, N. Pant, and N. Pal. 1989. Studies on the removal of some toxic metal ions. Part II. Removal of lead and cadmium by montmorillonite and kaolinite. Environ. Technol, Lett. 10 275-282. 

The former can reduce lead and mercury ions from 18-19.5 ppm to 0.005 and 0.05 ppm, respectively, in 7 h. The latter can take mercury ion from 20 ppm to less than 10 ppb in 2 h. Unless much shorter times can be used, these may be impractical for commercial use. Microspheres of poly(hy-droxyethyl methacrylate-co-ethylene glycol dimethacrylate) containing the aminoazosulfonate dye Congo red, have been used for removal of cadmium ion from water.63 The beads can be used repeatedly. They have not yet been tried on other metal ions. 

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