Browse

A detailed study has been conducted to investigate the leaching behavior of low-grade secondary type, uranium minerals under alkaline conditions. Uranium mapping analysis indicated the significance of each particle size to the leaching process. Owed to its significance, particle size effects were examined by two different experimental schemes: classical plate agita tion and bottle roll te sting. Other infl uencing variables such as agitation time and concentration of used lixiviants, were also considered. Results ...

In the world, over 18 million vehicles are rejected annually from operation. The spent catalysts are obtained from th e vehicles at the end of their life cycle as well as the vehicles which do not meet the prescribed st andards in the ECO test respected to the composition of exhaust gases. The basis of each catalyst is a ceramic monolith with deposited valuable platinum metals. The spent catalysts are solid waste and also the rich raw material for recovery of precious metals. The aim of this paper is a separation ...

In this study, the boric aci d extraction from colemanite in ammonium chloride was studied and the effects of parameters such as the leaching temperature, ammonium chloride concentration, solid/liquid ratio a nd leaching time were investigated on the boric acid extraction from colemanite. Statistical design of experiments and the analysis of variance were carried out. The experiments were performed in a 500-mL cylindrical glass reactor equipped with a mechanical stirrer, a thermostat for controlling the leaching t...

It is proposed to process gold mine man-made wastes through ultrasonic activation of source materials in water, then in an alkaline solution with subsequent cyanidation of gold-impregnated cakes, or direct cyan idation and sorption conditioning of gold multicomponent solutions with nano-structured anionite an av erage radius of pores of which is within 600-700 Ǻ that contains no more than 6-8% of strong-base groups. A preliminary withdrawal of elements accompanying gold ensures obtaining of good- quality target me...