The aluminium electrolytic plants generate PAH and fluoride contaminated wastes which are usually classified as hazardous material. These residues are generally disposed in secure landfill sites. A flotation cell process was previously developed to remove PAH from these aluminium industry wastes. The tests were done on composite samples made of particle size fractions under 50mm. The efficiency...

Solid/liquid separations are commonly the first step in any wastewater treatment. Such technologies are mature and new developments are rare. However, in the last decade some significant improvements in separation techniques for industrial wastewater pretreatment have been implemented. Advances in the technology include more efficient, faster centrifugal mixing of treatment chemicals and wastew...

Traditional nanostructured design of cerium oxide catalysts typically focuses on their shape, size, and elemental composition. We report a different approach to enhance the catalytic activity of cerium oxide nanostructures through engineering high density of oxygen vacancy defects in these catalysts without dopants. The defect engineering was accomplished by a low pressure thermal activation pr...

The present investigation deals with the recovery of iron values from the screw classifier overflow slimes from an iron ore washing plant by means of reverse cationic flotation as an alternate to direct anionic flotation. Selectivity index, an indicator of separation efficiency, was chosen as the response parameter for optimizing the quantity and evaluating a series of generically same but chem...

Flotation is one of the most important mineral concentration techniques. It is known that the appearance of the froth in the flotation cells tells much about the state of the flotation process. A machine vision measurement device was used to compute dynamical, morphological and colour variables of the froth on the top of a flotation cell during a set of experiments. In order to examine the depe...

Treatment of Ce[N(SiHMe(2))(2)](3)(thf)(2) with the chlorinating agents PhICl(2), Ph(3)CCl or C(2)Cl(6) gave the homoleptic Ce(IV) silylamide Ce[N(SiHMe(2))(2)](4). When performed in the absence of donating (solvent) molecules, the trivalent cluster Ce(5)[N(SiHMe(2))(2)](8)Cl(7) was isolated.

The restricted environmental stimulation technique or REST is a method of relaxation where the level of environmental sensory inputs is kept very low. A particular REST technique called tank flotation, or flotation REST, consists of 1 h sessions in a tank containing water with a high salt content and maintained at 35.5 degrees C. In this protocol, five normal subjects were studied before and du...

Time-of-flight ~TOF! inelastic neutron-scattering spectra were measured on b-cerium ~double hcp! and g-cerium ~fcc! near the phase-transition temperature. Phonon densities of states ~DOS! and crystal-field levels were extracted from the TOF spectra. A softening of the phonon DOS occurs in the transition from bto g-cerium, accounting for an increase in vibrational entropy of DSvib 5(0.0960.05)kB...

-This paper studies several kinetic aspects of semi-batch flotation of celestite and calcite in a mechanical or subaeration cell with sodium oleate as the collector agent, using pure minerals ranging in size between 177 and 74 pm, respectively, with a constant pH = 9 in the flotation bath in all experiments. The results obtained indicate that both minerals float rapidly and that the flotation r...

A flotation pre-treatment study for the separation of enargite (Cu3AsS4) from chalcopyrite (CuFeS2) ores of different origins was investigated in this work. The copper ore bearing enargite mineral contained 5.87mass% As and 16.50mass% Cu while the chalcopyrite bearing ore contained 0.32mass% As and 21.63mass% Cu. The two ore samples were mixed at 7 : 3 (enargite : chalcopyrite) by weight ratio ...