Cadmium, removal

Colella, C., DeGennarao, M., Langella, A., and Pansini, M. (1995). Cadmium removal from wastewaters using chabazite and phillipsite. Natural zeolites 93 occurrence, properties, and use, D. W. Ming and F. A. Mumpton, eds., International Committee on Natural Zeolites, Brockport, NY, 377-384. 

Alonso,A.I., Urtiaga,A.M., Zamacona, S., Irabien, A. and Ortiz, I. (1997) Kinetic modelling of cadmium removal from phosphoric acid by non-dispersive solvent extraction. Journal of Membrane Science, 130, 193. 

A study of iron, cadmium and lead mobility in remote mountain streams of California by Erel et al. (1990) showed that the excess of atmospheric pollution-derived lead and cadmium is rapidly removed downstream. The comparison of truly dissolved, colloidal, and surface particle concentrations measured in the stream with the results of a model of equilibrium adsorption indicates that the mechanism of removal in this organic-poor environment is essentially by uptake onto hydrous iron oxides. The experimentally determined partition coefficients (Dzomback and Morel, 1990) explain the behavior of lead however, they fail to explain the cadmium removal. It is proposed by the authors that cadmium is taken up by surfaces other than hydrous iron oxides. 

Kontrec J, Kralj D, and Brechevich L. Cadmium removal from calcium sulphate suspension by liquid membrane extraction during recrystallization of calcium sulphate anhydrite. Colloids Surf A Physicochem Eng Aspects, 2003 223(1-3) 239-249. 

C. Venkobachar and A. K. Bhattacharya, Cadmium Removal from Domestic Waters by a Low Cost Sorbent, Water Supply, 3, 157-163 (1985). 

Cyanuric Acid. Organic cyanurates and isocyanurates have been prepared as pure materials and their use as metal precipitants has been reported in the literature (25-25). Diallylisocyanurate salts of cadmium, copper, and lead have been described and polyisocyanurates have been cited as precipitants for monovalent and divalent metal ions — including Cd, Hg and Pb —from waste streams (26). Initial tests with 10-34-0 (pH 6.8) indicated that ammonium cyanurate was soluble in the media however, no measurement of the solubility was made and no precipitate was observed. Addition of ammonium cyanurate to a 10-30-0 (pH 6.0) grade phosphate fluid fertilizer containing 40 ppm cadmium indicated low solubility of the reactant in the media and resulted in no cadmium removal at stoichiometries ranging from 25 to 480%. Confirmatory tests... 

Massaccesi, G., Romero, M. C., Cazau, M. C., and Bucsinszky, A. M. (2002). Cadmium removal capacities of filamentous soil fungi isolated from industrially polluted sediments, in La Plata (Argentina). World J. Microbiol. Biotechnol. 18, 817-820. 

Prabhukumar, G., Matsumoto, M., Mulchandani, A., and Chen, W. (2004). Cadmium removal from contaminated soil by tunable biopolymers. Environ. Sci. Technol. 38(11), 3148-3152. 

Sznejer, G. and Marmur, A. (1999). Cadmium removal from aqueous solutions by an emulsion liquid membrane. The effect of resistance to mass transfer at the outer oil-water interface. Colloids Surf. A, 151, 77-83. 

Summary of results for cadmium removal from a zinc sulphate liquor RCE diameter 22.9 cm RCE area 1630 cm2 rotation speed 540 rev min l zinc concentration 127 g dm-3 catholyte temperature 60°C... 

Benguella, B., Benaissa, H., 2002. Cadmium removal from aqueous solutions by chitin kinetic and equilibrium studies. Water Res. 36, 2463-2474. 

From the mixing chamber the dusts are entrained with the gas flow and are transported as a suspension through the cooler. The heat is recovered as high pressure steam. In the primary cyclone separation stage, the coarser dusts are returned to the mixing chamber. The process gases are then cleaned using two electrofilters. To maintain the amount of dust in circulation at the desired level, the system is equipped with a controllable outlet for dust. The precipitated flue dust removed form the FluxFlow system is fed back to the process after treatment for chlorine and cadmium removal. 

Sudha et al. (2008) and Dinesh Karthik et al. (2009) reported on the removal of heavy metal cadmium and chrominm from industrial wastewater using chitosan-coated coconut charcoal and chitosan impregnated polyurethane foam, respectively. Adsorption and determination of metal ions such as zinc (11) and vanadium (II) onto chitosan from seawater have been studied (Muzzarelli et al. 1970, Muzzarelli and Sipos 1971, Muzzarelli and Rocchetti 1974). Adsorption of strontium (II), cobalt (11), zinc (11), and iron (III) on chitosan from sodium chloride solution have been reported (Nishimura et al. 1995). Adsorption behavior of Cu (II) (Minamisawa et al. 1996, Wu et al. 2000) and cobalt (11) (Minamisawa et al. 1999) were investigated. The amount of cadmium removed by chitin increases with increase of these parameters at a specific time. The application to experimental results of the Langmuir and Freundlich models shows that the Langmuir model gives a better correlation coefficient. 

Sousa Neto VO, Carvalho TV, Honorato SB, Gomes CL, Barros FCF, Araujo-Silva MA, Freire PTC, Nascimento RF. Coconut bagasse treated by thiourea/ammonia solution for cadmium removal kinetics and adsorption equilibrium. BioResources 2012 7 1504-1524. 

Gupta VK, Nayak A. Cadmium removal and recovery from aqueous solutions by novel adsorbents prepared from orange peel and Fe203 nanoparticles. Chem Eng J... 

Mahalakshmi M, Arabindoo B, Palanichamy M, Murugesan V (2007) Photocatalytic degradation of carbofuran using semiconductor oxides. J Hazard Mater 143(l-2) 240-245 MaUou E, Malamis M, Sakellarides PO (1992) Lead and cadmium removal by ion exchange. Water Sci Technol 25(1) 133-138... 

Metal biosorption-flotation, application to cadmium removal. Appl... 

Belhalfaoui, B., Aziz, A., Elandaloussi, E. H., Ouali, M. S., and L. C. Me norval. 2009. Succinate-bonded cellulose A regenerable and powerful sorbent for cadmium-removal from spiked high-hardness groundwater. J. Hazard. Mater. 169 831-837. 

Benguella and Benaissa (2002) studied the adsorption of cadmium from a 100 mg/L aqueous solution onto chitin at initial pH between 5.7 and 6.4. The maximum cadmium removal capacity of chitin was 12.5 mg/g at a load of 2 g/L. They followed this study by evaluating the effect of several ions (Na+, Mg +, Ca +, CL, SO , and CO ") on the kinetics of cadmium sorption onto chitin. The authors found that Ca and C03 had a large inhibitory effect over cadmium adsorption, while Mg + and had a weak inhibitory effect. At the same time, Na and CL were found to have no effect on cadmium adsorption. Most of these studies focused on either single metal removal or on the effect of competitive ions on metal removal. 

The kinetie and equilibrium studies were done on the removal of cadmium Ifom aqueous solutions using chitin as an adsorbent by Benguella and Benaissa (2002). The effect of particle size of chitin on the cadmium removal was studied using six particle size groups such as 0- 0.20 0.20-0.63 0.63-1.25 1.25-2.50 2.50-4.10 4.10-6.30 mm. The increase in cadmium sorption capacity at the equilibrium with the decrease of ehitin partiele sizes indicates that cadmium ion sorption occurs by a surface meehanism. Similar results have been reported for the sorption of metal ions by natural polymers and their derivatives [211]. 

The variation in particle size appears to have an influence on the time required for equilibrium. The observed results reported that the time required to reach equilibrium is about Ih for particle sizes of 0.2 mm, with a quantity of eadmium removed at an equilibrium of 13.57 mg/g ehitin while for partiele sizes 4.1-6.3 mm, the time neeessary is about 4 h with a weak eapaeity of cadmium removal of about 7.5 mg/g chitin. 

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