A STUDY ON KINETICS OF LEAD, ZINC, IRON, COPPER AND NICKEL SORPTION ONTO IMMOBILIZED HUMIC SUBSTANCES

The rates of oxidative rancidity of peanut oil in contact with iron, copper, zinc, aluminum, tin, polyethylene (PE), glass and magnesium were studied. The rancidity of the oil in the surfaces made of these materials decreased in the order Mg>Fe>Cu>Sn>Glass>Zn>Al>PE. The order obtained showed that the rancidity process does not depend on the activity of these surfaces, but has a possible link with surface passivity. The values for the rate of rancidity in Mg and Fe surfaces where the process was fastest were 2.08 × 10-5 and 1.39 × 10-5 mmolkg-1hr-1 respectively, while values for the lowest rates of rancidity obtained for Al and PE surfaces were 2.78 × 10-6 and 1.07 × 10-6 mmolkg-1hr-1 respectively. The use of aluminum and PE vessels for the storage of peanut oil would increase its shelf-life by keeping the oil in its original state for a longer period of time.

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Kinetics of barite reduction from refractory barite-sulphide ore

Metallurgical and Materials Engineering ◽

10.30544/237 ◽

2016 ◽

Vol 22 (4) ◽

pp. 261-268 ◽

Cited By ~ 1

Author(s):

Miroslav D Sokić ◽

Vladislav Matković ◽

Jovica Stojanović ◽

Branislav Marković ◽

Vaso Manojlović

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Kinetic Model ◽

Copper Sulphide ◽

Influence Of Temperature ◽

Sulphide Ore ◽

Lead Zinc ◽

Complex Structural ◽

Kinetics Of ◽

Maximum Removal

Refractory sulphide–barite ore was reduced with carbon in order to release lead, zinc, and copper sulphide from barite-pyrite base. Mineralogical investigations showed that due to the complex structural-textural relationships of lead, copper and zinc minerals with gangue minerals, it is not possible to enrich the ore using the conventional methods of mineral processing. The influence of temperature and time was studied to optimize the conditions, and to determine the kinetics of the barite reduction. The maximum removal of barite from ore was 96.7% at 900oC after 180 min. Chemically controlled kinetic model showed the best compliance with the experimental data. An activation energy of 142 kJ/mol was found.

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Desulfurization kinetics of high lead and zinc sulfide containing slag with oxygen blowing

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb190121026y ◽

2019 ◽

Vol 55 (2) ◽

pp. 187-196

Author(s):

K. Ouyang ◽

Z.-H. Dou ◽

T.-A. Zhang ◽

Y. Liu ◽

L.-P. Niu

Keyword(s):

Zinc Sulfide ◽

Spinel Phase ◽

Xrd Analysis ◽

Smelting Process ◽

Experimental Conditions ◽

Lead And Zinc ◽

Desulfurization Process ◽

Lead Zinc ◽

Kinetics Of ◽

High Lead

The desulfurization process of lead and zinc slag is an important smelting process to obtain lead and zinc. The aim of this paper is to study the desulfurization process of high lead and zinc sulfide containing slag with oxygen blowing. The predominance area diagrams of the Pb-Zn-Fe-S-O system (Pb/(Fe+Pb+Zn)=0.176, Zn/(Fe+Pb+Zn)=0.56) at various temperature were thermodynamically constructed. The physical properties, the chemical composition and the phase transformation of the desulfurization slag were investigated. The thermodynamic results indicated that lead, zinc, and iron can be oxidized to form high lead and zinc slag. The experimental results illustrated that the sulfur content in the oxidation slag can be reduced to less than 1% as temperature increased up to 1573 K. The XRD analysis of as-quenched slag shows the PbS and ZnS phase decreased, while zincite and spinel phase (ZnxFe3-xO4+y) emerged and increased as the reaction time increased. The desulfurization process of molten slag were considered to be the first-order reaction and the apparent activation energy was estimated to be 44.46 kJ/mol. Under the experimental conditions, the mass transfer in the gas and liquid phase was likely to be the restrictive step.

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KINETICS OF SINGLE AND MULTIPLE METAL ION SORPTION PROCESSES ON HUMIC SUBSTANCES

Soil Science ◽

10.1097/00010694-199608000-00006 ◽

1996 ◽

Vol 161 (8) ◽

pp. 509-520 ◽

Cited By ~ 29

Author(s):

X. Jin ◽

G. W. Bailey ◽

Y. S. Yu ◽

A. T. Lynch

Keyword(s):

Humic Substances ◽

Metal Ion ◽

Ion Sorption ◽

Kinetics Of

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Interactive Effects of Metals in Mixtures on Biomass Production Kinetics of Freshwater Copepods

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f80-165 ◽

1980 ◽

Vol 37 (8) ◽

pp. 1295-1302 ◽

Cited By ~ 22

Author(s):

Uwe Borgmann

Keyword(s):

Binary Mixtures ◽

Biomass Production ◽

Metal Toxicity ◽

Interactive Effects ◽

Growth Time ◽

Metal Mixtures ◽

Metal Interactions ◽

Lead Zinc ◽

Freshwater Copepods ◽

Kinetics Of

The effect of metal mixtures on the biomass production rates of natural assemblages of copepods was predicted by assuming that metal-induced increases in the inverse of the growth rate (i.e. the growth time) are additive. The average observed growth time increase, ΔGTobs in 14 binary mixtures of the metals Cd, Cu, Hg, Pb, Zn, and As was 17% larger than the average calculated growth time increases, ΔGTcal (assuming additivity), indicating a slight but statistically significant synergism. Synergism in multimetal mixtures appears to be cumulative, since the average ΔGTobs was 53% greater than the average ΔGTcal in mixtures containing five metals simultaneously. One of the 15 possible binary mixtures (Zn:As) of the six metals tested demonstrated a large divergence between ΔGTobs and ΔGTcal. For all other metal mixtures studied, most of the toxicity is accounted for by the summation of noninteractive, single, metal effects.Key words: copepods, metal toxicity, metal interactions, biomass production, cadmium, copper, mercury, lead, zinc, arsenic

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