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Influence of polymers on the grinding and rheology of ultrafine Egyptian calcium carbonate suspension

Mourad Sabreen H, Khalil Mostafa M. H., Abdel-Khalek N. A., Abdel-Khalek M. A., Selim K. A., Hassan El-Sayed R. E.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 152163

EN

The investigation of surface modification of Egyptian calcium carbonate via polymers was achieved with simultaneous ultra-fine grinding. Attrition mill and planetary mill were used for wet and dry grinding, respectively. The parameters affecting the grinding were studied such as ball number, speed and grinding time. The rheological characteristics of the aqueous calcium carbonate suspensions were studied in the presence of different types of polymers. The results indicated that the mechanical force could clearly affect the modification characteristics of calcium carbonate due to its mechanochemical effects. The viscosity of calcium carbonate suspension depends on the volume percentage or weight percentage. The dispersing agent increases the solid concentration for a given particle fineness.

2

Mineralogical study and enhanced gravity separation of gold-bearing mineral, South Eastern Desert, Egypt

El-Sayed Samah, Abdel-Khalek N. A., El-Shatoury E. H., Abdel-Motelib A., Hassan M. S., Abdel-Khalek M.A.

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 5

839--848

EN

El-Hudi gold deposit, located in the South Eastern Desert of Egypt, represent large vein- type gold occurrence. The representative sample revealed the abundance of quartz as main constituent with minor amounts of mineral impurities. Gold was detectable (12 g/t) as determined using atomic absorption. The petrographic study revealed that the gold grains ranged from 10-40 μm. The grain boundaries of quartz are highly stained with iron minerals as hematite and limonite. Sericite mineral is common in discrete gold-bearing veins. Eroded pyrite was detected with high alteration leaving only cubic-shaped cavities behind. Different techniques for gravity separation were used to separate gold from the quartz mineral. After crushing and grinding of the sample, shaking table was used to upgrade the coarser fractions while Falcon concentrator was employed to upgrade the fine fraction. The best concentrate was obtained through grinding the whole sample to less than 0.2 mm, followed by cleaning steps. The gold content is increased from 12 to 145 g/t with total recovery of 78%.

3

Physicochemical study of dye removal using electro-coagulation-flotation process

El-Hosiny F. I., Abdel-Khalek M. A., Selim K. A., Osama I.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

321--333

EN

The performance of electro-flotation with aluminum electrodes for the removal of different dyes from synthetic aqueous solutions and real wastewater was studied. Parameters affecting the electro-coagulation-flotation process, such as pH, initial dye concentration, treatment time and temperature were investigated. The maximum dye removal from synthetic solutions was achieved at pH 7. The order of the dye removals is nonionic>cationic>anionic. The removal process follows pseudo first-order kinetics and the adsorption follows both physical and chemical adsorptions which is exothermic. Negative values of entropy change, ΔS°, and Gibbs free energy change, ΔG°, indicate that this adsorption process is spontaneous and less favorable at high temperatures. Treatment of a real wastewater from textile dyeing factory showed that the removal efficiency was ranging between 92-99% for all constituents. The energy consumption is 0.0167 kWh/dm3.