Experimental Procedure for the Determination of the Critical Coalescence Concentration (CCC) of Simple Frothers

In this study, the critical coalescence concentrations (CCC) of selected commercial frother solutions, namely polypropylene glycols (PPG 200, 400, and 600), tri propylene glycol (BTPG), triethylene glycol (BTEG), dipropylene glycol (BDPG), and as a reference, methyl isobutyl carbinol (MIBC), were determined using a bubble column based on light absorption. The results for all seven frothers showed that BTEG has the worst bubble inhibiting performance, and PPG 600 has the best bubble inhibiting performance. While critical coalescence concentration (CCC) was found as 3 ppm for PPG 600, it increased to 25 ppm for BTEG. In the case of MIBC, which was the reference point, the CCC value was found as 10 ppm, which was consistent with the literature. The surface tension isotherms of the frothers were determined and analyzed with one of the latest adsorption models. The results indicated that the polypropylene glycol frothers showed more surface activity compared to alcohol or other frothers investigated. This is due to the additional reorganization of the PPG molecules on the air/water interface, thus boosting its surface activity.

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Adsorption Kinetics of Various Frothers on Rising Bubbles of Different Sizes under Flotation Conditions

Minerals ◽

10.3390/min11030304 ◽

2021 ◽

Vol 11 (3) ◽

pp. 304

Author(s):

Khandjamts Batjargal ◽

Onur Guven ◽

Orhan Ozdemir ◽

Stoyan I. Karakashev ◽

Nikolay A. Grozev ◽

...

Keyword(s):

Pore Size ◽

Triethylene Glycol ◽

Major Effect ◽

Methyl Isobutyl ◽

Sauter Mean Diameter ◽

Flotation Cell ◽

Resident Time ◽

Bubble Sizes ◽

Kinetics Of

This paper studies the effect of the type and concentration of selected frothers, the gas flowrate, and the pore size of the porous frit on the bubble sizes (Sauter mean diameter, SMD) of bubbling flow produced in a micro-flotation cell, and the determination of bubble size distribution (BSD) in the presence of the frothers. The commercial frothers polypropylene glycols (PPG 200, 400, and 600), tri propylene glycol (BTPG), triethylene glycol (BTEG), dipropylene glycol (BDPG), and Methyl Isobutyl Carbinol (MIBC) were used in the present investigation. The frother concentration varied from 1 to 1000 ppm. The flow rate varied in the range of 25 to 100 cm3/min. The pore sizes of the frit were selected as 10–16 μm, 16–40 μm, and 40–100 μm. Each frother exhibited its own unique ability in preventing coalescence of the bubbles in the order of BTEG < BDPG < PPG 200 < MIBC < BTPG < PPG 400 < PPG 600. The factorial experiments established that the type of the frother and its concentration have a major effect on the size of the bubbles. The bubbles decreased twice their size when the frother concentration was increased from 1 ppm to 1000 ppm. The pore size of the frit is a significant factor as well. The size of the bubbles can be reduced from about 10% to about 40% by decreasing the pores from 40–100 μm to 10–16 μm but the level of this decrease depends on the type of the frother. The increase of the flowrate from 25 cm3/min to 100 cm3/min produced bubbles smaller by 25% to 50% for the case of BTEG, BDPG, PPG 200, MIBC, BTPG, while a minimum of the bubble sizes was reached for the case of PPG 400 and PPG 600, beyond which the bubbles enlarged their size. The BSD in the presence of PPG 600 varied around 0.3 mm, whereas BTEG gave a wider BSD which indicated that the type of frother affected the bubble production. Our analysis shows that the first group of frothers adsorbs instantly on the bubbles, once they leave the porous frit, thus reaching equilibrium. PPG 400 and PPG 600 adsorb significantly slower on the bubbles, possibly not reaching equilibrium during their resident time.

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Surface Activity of Newly Nonionic Surfactants at Air/Water Interface and their Interaction with Clay and Teflon

Tenside Surfactants Detergents ◽

10.3139/113.100371 ◽

2008 ◽

Vol 45 (3) ◽

pp. 137-143 ◽

Cited By ~ 2

Author(s):

R. Abdel-Rahem ◽

A. S. Ayesh

Keyword(s):

Surface Activity ◽

Nonionic Surfactants ◽

Water Interface ◽

Air Water Interface

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Determination of Some Nitrophenols by Atomic Absorption Spectrometry (AAS) After Extraction of Ionic Associates Involving the Bipyridylocopper(II) or Phenanthrolinocopper(II) Complex

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19942227 ◽

1994 ◽

Vol 59 (10) ◽

pp. 2227-2234 ◽

Cited By ~ 2

Author(s):

Václav Stužka ◽

Jaromír Souček

Keyword(s):

Molecular Weight ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Methyl Isobutyl Ketone ◽

Absorption Spectrometry ◽

Methyl Isobutyl ◽

Isobutyl Ketone ◽

Indirect Determination ◽

Ionic Associates

A new method has been developed for the indirect determination of nitroso- and nitrophenols by atomic absorption spectrometry (AAS) after extraction of ionic associates involving bipyridylocopper(II) (CuDP) or phenanthrolinocopper(II) (CuPH) complexes. Nitrobenzene and methyl isobutyl ketone appeared to be suitable for the extraction. It was possible to determine several tenths to hundredths of a milligram of nitrophenol in a litre. Extractable associates with CuDP and CuPH are formed by phenols possessing two substituents or by higher molecular weight phenols such as naphthol or hydroxyquinoline. Monosubstituted phenols fail to form associates of this kind.

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Migration of mineral oil in elastomers

Journal of Rubber Research ◽

10.1007/s42464-021-00087-7 ◽

2021 ◽

Author(s):

Tobias Förster ◽

Artur Blivernitz

Keyword(s):

Diffusion Coefficients ◽

Mineral Oil ◽

Activation Energies ◽

Concentration Profiles ◽

Small Reservoir ◽

Experimental Procedure ◽

Mineral Oils ◽

The Absolute ◽

Suitable Measure

AbstractThis work describes a newly introduced experimental procedure to quantify the diffusion progress of mineral oils locally resolved in NBR. Diffusion of reference oils IRM 901, IRM 902 and IRM 903 in NBR with various acrylonitrile contents was investigated. Classical sorption experiments were performed as a basic characterization and compared to the newly introduced method. Here, elastomer specimens are only being dipped with the bottom in a relatively small reservoir of mineral oil. This provides a determination of locally resolved concentration profiles of mineral oils, and the calculation of diffusion coefficients. These diffusion coefficients follow the same trends like those determined via sorption experiments. Despite differences in the absolute numbers, activation energies of diffusion can be applied as a suitable measure for the compatibility of elastomers and fluids.

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On factors affecting surface free energy of carbon black for reinforcing rubber

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0015 ◽

2020 ◽

Vol 9 (1) ◽

pp. 170-181 ◽

Cited By ~ 2

Author(s):

Shangyong Zhang ◽

Ruipeng Zhong ◽

Ruoyu Hong ◽

David Hui

Keyword(s):

Free Energy ◽

Carbon Black ◽

Surface Free Energy ◽

Surface Activity ◽

Gas Flow ◽

Influential Factors ◽

Chromatographic Column ◽

Factors Affecting ◽

Carrier Gas Flow

AbstractThe surface activity of carbon black (CB) is an important factor affecting the reinforcement of rubber. The quantitative determination of the surface activity (surface free energy) of CB is of great significance. A simplified formula is obtained to determine the free energy of CB surface through theoretical analysis and mathematical derivation. The surface free energy for four kinds of industrial CBs were measured by inverse gas chromatography, and the influential factors were studied. The results showed that the aging time of the chromatographic column plays an important role in accurate measurement of the surface free energy of CB, in comparison with the influences from the inlet pressure and carrier gas flow rate of the chromatographic column filled with CB. Several kinds of industrial CB were treated at high temperature, and the surface free energy of CB had a significant increase. With the increase of surface free energy, the maximum torque was decreased significantly, the elongation at break tended to increase, the heat generation of vulcanizates was increased, and the wear resistance was decreased.

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Determination of the pore size of woven structures through image analysis

Open Engineering ◽

10.2478/s13531-011-0045-2 ◽

2012 ◽

Vol 2 (1) ◽

Cited By ~ 5

Author(s):

R. Angelova

Keyword(s):

Pore Size ◽

Single Layer ◽

Woven Fabric ◽

Virtual Model ◽

Experimental Procedure ◽

Porosity And Permeability ◽

Woven Structures ◽

Woven Structure ◽

Non Destructive

AbstractThe paper presents an experimental procedure developed for determination of the pore size, shape and distribution in a single layer woven fabric, for the construction of a virtual model to be incorporated in a future CFD software package. The procedure is based on non-destructive observation and analysis of woven samples. 14 different samples of gray fabrics of 100 % cotton in plain and twill weaves are investigated. The results obtained allow the creation of reality more realistic virtual model of the woven structure, and theoretical investigation of its porosity and permeability through computer simulation.

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