Adsorption of Ions Dilute Aqueous Solutions on Glass and Plastic Surfaces.

Eichholz, Geoffrey G.; Nagel, Alessandro; Hughes, R.B.

doi:10.1021/ac60226a020

Cited by 54 publications

(7 citation statements)

References 18 publications

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“…In a study using radioactive tracers, Robertson ( I ) analyzed the adsorption of 11 elements in sea water on various containers and indicated that optimum conditions for storing sea water were achieved by acidifying to pH 1.5 immediately after collec- tion and storing in polyethylene containers. After studying somewhat different ions in hard water, Eicholz et al (2) reported that it was preferable to use borosilicate glass, rather than polyethylene, to minimize container ion adsorption. Adsorption of silver by containers appears to vary with concentration, pH, contact time with the container, composition of dissolved salts, type of containers, and complexing agents (3)(4)(5)(6)(7).…”

Section: Resultsmentioning

confidence: 99%

Thermometric titration determination of hydroxide and alumina in Bayer process solutions

VanDalen¹,

Ward²

1973

Anal. Chem.

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The apparatus determines from 10 to 600 grams/l. hydroxide and from 3 to 120 grams/l. alumina in Bayer Process streams. Essential components include a constant rate buret, a glass enclosed thermistor, and a specially designed operational amplifier circuit which by generating the first derivative' of the thermistor signal, detects the end point and stops the titration. The sample is diluted with sodium tartrate and titrated with 1 . 3 N HCI in a thermos jar. The first titration volume is equivalent to hydroxide; after the addition of potassium fluoride, the second titration volume is equivalent to alumina. The complete titration takes 4 minutes. Suspended solids do not interfere, neither do other constituents in Bayer liquors. The relative standard deviation is 0.32% for hydroxide at the 180 grams/l. level, and 0.17% for alumina at the 120 grams/l. level.Good analytical values for hydroxide and alumina are needed to efficiently operate the Bayer Process, in which hot sodium hydroxide is used to dissolve the alumina from bauxite to give a concentrated solution of alumina. Impurities such as iron oxide, titania, and sand are left behind as insolubles, commonly referred to as red mud. After filtering off the red mud, the dissolved alumina is recovered from the filtrate by allowing it to cool, and then seeding it with aluminum hydroxide. About one half of the alumina precipitates out by this procedure. The Bayer Process control strategy involves constant measurement of the concentrations of hydroxide, which in North America is traditionally ( I ) expressed as grams/l. NaZC03, and of alumina, which is expressed as grams/l. A1203. In some cases the ratio of the alumina to hydroxide concentrations is used for process control. This ratio is related to the degree of saturation of the solution; it has values of less than 0.5 for saturated solutions, and values up to 0.7 for supersaturated solutions, which are fed to the precipitators.Thermometric titrations have been used to determine caustic ( 2 ) and alumina (3) in 2-or 3-component solutions. These methods are not well suited for routine, process control analyses, since the titration must be continued beyond the equivalence point, and a strip chart recording of the titration curve must be inspected to locate the end point. Zenchelsky and Segatto ( 4 ) were the first to point out that thermometric titration curves can be differentiated. They demonstrated this by mechanical amplification of the bridge signal followed by differentiation of the amplified signal in a resistance-capacitance network. Later, a much simpler operational amplifier circuit ( 5 ) was used to generate the first and second derivatives 1 Present address, Aluminum Company of Canada, Limited, Kitimat, British Columbia, Canada.

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Section: Resultsmentioning

confidence: 99%

Thermometric titration determination of hydroxide and alumina in Bayer process solutions

VanDalen¹,

Ward²

1973

Anal. Chem.

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“…Contamination, interferences, and adsorption phenomena are special worries of the microanalyst. Therefore, the study by Eichholz, Nagel, and Hughes on the adsorption of ions on glass and plastic surfaces is of interest (37). Likewise, the phosphate studies by Heron are significant.…”

Section: Reviews and General Discussionmentioning

confidence: 99%

Inorganic Microchemistry

West¹

1966

Anal. Chem.

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The be view of inorganic microchemistry is contiguous with the previous review (160) and extends through December 1965. Because many techniques such as chromatography, ion exchange, extraction, nucleonics, spectroscopy, and microscopy, which are of importance in inorganic microchemistry, are reviewed as separate topics, only brief mention will be made of them in this discussion and the reader is referred to the accompanying specialized reviews for more complete orientation.It is obvious from the previous reviews of inorganic microchemistry that no real distinction is made between trace analysis and microchemistry, although many specialists feel that there is a great difference between these fields. This reviewer feels that the problems of trace studies and microanalysis are often so

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“…Procedures have been developed to monitor the different species of phenol generated such that they are below toxic levels in a variety of matrices (Fichnolz et al, 1965;West et al, 1966;. Generally, the sample which is thought to contain phenol has its pH changed to non-neutral pH values to minimize microbial degradation and stored in brown glass vials to decrease the loss to adsorption and photodecomposition, respectively (Afghan et al, 1974).…”

Section: Sampling and Cleanupmentioning

confidence: 99%

New Perspectives in Biosensors Technology and Applications

Serra¹

2011

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Adsorption of Ions Dilute Aqueous Solutions on Glass and Plastic Surfaces.

Cited by 54 publications

References 18 publications

Thermometric titration determination of hydroxide and alumina in Bayer process solutions

Thermometric titration determination of hydroxide and alumina in Bayer process solutions

Inorganic Microchemistry

New Perspectives in Biosensors Technology and Applications

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