The Flotation Separation of Magnesite and Limonite Using an Amine Collector

In order to reduce the iron impurities in magnesite ore and improve the purity of magnesium products, the difference in floatability between magnesite and limonite has been studied by using mixtures with a collecting agent—KD (cationic amine collectors, containing soluble components). Sodium hexametaphosphate, pH, sodium silicate, and sodium carboxymethyl cellulose were used as regulators. Adsorption mechanisms of the reagents on minerals were analyzed by a zeta potential analyzer and infrared spectroscopy. Sodium silicate increased the floatability of both minerals at 11.6. All the three regulators reduced the zeta potential of both minerals, while KD increased the zeta potential of magnesite and decreased the zeta potential of limonite. All the three regulators were likely chemically adsorbed on the surface of both minerals; KD has electrostatic adsorption on the surface of the minerals.

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Kaolinite-Magnesite Based Ceramics. Part I: Surface Charge and Rheological Properties Optimization of the Suspensions for the Processing of Cordierite-mullite Tapes

10.20944/preprints201911.0304.v1 ◽

2019 ◽

Author(s):

Aghiles Hammas ◽

Gisèle Laure Lecomte-Nana ◽

Nadjet Azril ◽

Imane Daou ◽

Claire Peyratout ◽

...

Keyword(s):

Zeta Potential ◽

Sodium Silicate ◽

Ph Value ◽

Tape Casting ◽

Casting Process ◽

Sodium Hexametaphosphate ◽

Cohesion Energy ◽

Limit Values ◽

Clay Slurry ◽

Kaolinitic Clay

The present study aimed at investigating the influence of the concentration of sodium silicate and sodium hexametaphosphate on the dispersion of an aqueous kaolinitic clay slurry regarding further use for the tape casting process. The zeta potential of the kaolinitic clay slurry matched the requirements for tape casting. The addition of magnesite in the kaolinitic slurries tended to increase the zeta potential towards the required limit values. Despite, the further addition of surfactants allowed improving the zeta potential in agreement with the tape casting conditions. Accordingly, the rheological behavior, under continuous and oscillatory flow conditions, of various mixtures of magnesite and a kaolinitic clay was studied. Regarding the pH and the zeta potential measurements, the E–F attraction prevailed at low pH value, and F–F or E–E attraction was predominant at high pH value. All slurries exhibited a shear thinning behavior, which was well-correlated by Herschel–Bulkley model. It appeared that the best stability for the kaolinitic clay slurries was obtained while using 0.4 mass% and 1.2 mass% of sodium hexametaphosphate and sodium silicate respectively. An increase in the magnesite concentration above 6 mass% led to a complex behavior with low cohesion energy due to the occurrence of soluble complexes.

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Kaolinite-Magnesite Based Ceramics. Part I: Surface Charge and Rheological Properties Optimization of the Suspensions for the Processing of Cordierite-Mullite Tapes

Minerals ◽

10.3390/min9120757 ◽

2019 ◽

Vol 9 (12) ◽

pp. 757 ◽

Cited By ~ 1

Author(s):

Aghiles Hammas ◽

Gisèle Lecomte-Nana ◽

Nadjet Azril ◽

Imane Daou ◽

Claire Peyratout ◽

...

Keyword(s):

Zeta Potential ◽

Sodium Silicate ◽

Ph Value ◽

Tape Casting ◽

Casting Process ◽

Sodium Hexametaphosphate ◽

Cohesion Energy ◽

Limit Values ◽

Clay Slurry ◽

Kaolinitic Clay

The present study aimed at investigating the influence of the concentration of sodium silicate and sodium hexametaphosphate on the dispersion of an aqueous kaolinitic clay slurry regarding further use for the tape casting process. The zeta potential of the kaolinitic clay slurry matched the requirements for tape casting. The addition of magnesite in the kaolinitic slurries tended to increase the zeta potential towards the required limit values. Despite this, the further addition of surfactants allowed improving the zeta potential in agreement with the tape casting conditions. Accordingly, the rheological behavior, under continuous and oscillatory flow conditions, of various mixtures of magnesite and a kaolinitic clay was studied. Regarding the pH and the zeta potential measurements, the E–F attraction prevailed at low pH value, and F–F or E–E attraction was predominant at high pH value. All slurries exhibited a shear thinning behavior, which was well-correlated by the Herschel–Bulkley model. It appeared that the best stability for the kaolinitic clay slurries was obtained while using 0.4 mass% and 1.2 mass% of sodium hexametaphosphate and sodium silicate, respectively. An increase in the magnesite concentration above 6 mass% led to a complex behavior with low cohesion energy due to the occurrence of soluble complexes.

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Adsorption behavior and corrosion rate model of sodium carboxymethyl cellulose (Na-CMC) polymer on aluminium in HCl solution

Nigerian Journal of Technology ◽

10.4314/njt.v39i2.7 ◽

2020 ◽

Vol 39 (2) ◽

pp. 369-378

Author(s):

O.M. Egbuhuzor ◽

I.C. Madufor ◽

S.C. Nwanonenyi ◽

J.O. Bokolo

Keyword(s):

Weight Loss ◽

Corrosion Rate ◽

Carboxymethyl Cellulose ◽

Water Bath ◽

Sodium Carboxymethyl Cellulose ◽

Time Interval ◽

Adsorption Behaviour ◽

Before And After ◽

The Difference ◽

Cr Concentration

Adsorption behaviour and corrosion rate of Sodium carboxymethyl cellulose on aluminium was studied. Different concentration levels of Sodium carboxymethyl cellulose (Na-CMC) solution were applied on several prepared and polished aluminium coupons for a corrosion experiment. These coupons were totally immersed in 100ml of 0.5M solution of Hydrochloric acid (HCl) in an open beaker placed in a water bath at varying temperatures for 2-8hrs respectively. At every specified temperature and time interval, the immersed coupon specimen was withdrawn from the test solution, washed, dried and reweighed. The weight loss being the difference in weight of the specimen before and after immersion in the water bath was recorded for every coupon sample. The effects of concentration, temperature and time on corrosion rate were studied and from the various plots, it was observed that increase in the concentration of the inhibitor decreases the corrosion rate. The study of the adsorption behaviour showed that Na-CMC was physically adsorbed on the aluminium coupons and obeyed Freundlich adsorption isotherm with an activation energy of 32K.83j/mol and heat of adsorption of -18.21Kj/mol . The study also established a relationship between the corrosion rate, CR; concentration, C; temperature, T; and time t, through a mathematical model: CR = 3.8-5*T1.1617 - 0.00052t0.6176 - 0.0013C0.8012, the proportion of variance explained (R2) = 0.8658 (86.58%), From the Results of the experiment and the model, Na-CMC was found to be an active corrosion inhibitor of Aluminium in acidic environment. Keywords: Adsorption, Aluminium, concentration, Corrosion Rate, Weight Loss

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EFFECT OF PH CONDITIONS ON GOETHITE BEHAVIOR IN THE PRESENCE/ABSENCE OF DIFFERENT DISPERSANTS

Contemporary Materials ◽

10.7251/comen2101091s ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Svjetlana Sredić ◽

Ljiljana Tankosić

Keyword(s):

Zeta Potential ◽

Surface Charge ◽

Sodium Silicate ◽

Ph Value ◽

Sodium Hexametaphosphate ◽

Surface Charges ◽

Effect Of Ph ◽

Ph Values ◽

Ph Conditions ◽

Settling Behavior

Dispersion and settling behavior of goethite has been studied and effect of pH values on surface properties of goethite particles with /without dispersants has been discussed. A prerequisite for the successful flocculation is the stabilization of the system which is achieved by the good dispersion of particles. The effect of pH, sodium silicate (Na2SiO3), sodium hexametaphosphate (Na6P6O18) and sodium pyrophosphate (Na4P2O7), on the surface charges of goethite was studied. The IEP of natural goethite was found by measuring zeta potential at pH value of 6.6. With the use of sodium silicate the IEP of goethite moves to pH 4.95. An IEP could not be detected when the poly-phosphates were used and the surface charge is negative from pH 2 to pH 12. The relatively high zeta potential values indicate a fairly stable dispersion, especially when the sodium hexametaphosphate were used as dispersant.

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