This study addresses the feasibility of removing Cu and Ni from sludges of printed circuit board (PCB) plants by acidic extraction. Citric acid, acetic acid, hydrochloric acid, nitric acid, and sulfuric acid at various concentrations were experimentally examined to determine preferred conditions for removing Cu and Ni. Experimental results indicate that the removal ratios of Cu were 57% (citric...

  Abstract   The effect of mechanical activation using an attrition mill on the particle size of an ilmenite concentrate and its effect on the ability of the concentrate for Iron separation during hydrochloric acid leaching and the kinetics of the dissolution process have been investigated. It was observed that mechanical activation in an attritor significantly enhances the dissolution of iron ...

1. The reaction of the sunfish, Eupomotis gibbosus, to different concentrations of hydrochloric acid and of the first six members of the N aliphatic acids has been studied. 2. The stimulating efficiency of hydrochloric acid may best be related to the concentration of hydrogen ions produced by that acid. 3. The stimulating efficiency of the N aliphatic acids may best be correlated with the non-p...

Demineralization of bone for collagen extraction is most commonly performed using dilute hydrochloric acid (HCl) despite the fact that little data exists on the effects of differing acid concentration or treatment time on the quantity and quality of collagen extracts and that hydrochloric acid is extremely effective at hydrolyzing peptide bonds. Data on yield, elemental composition, and isotopi...

In a previous article (1)) on the secretion of gastric juice in fever, it was reported that the concentration of’ chlorides in gastric juice was constant or slightly reduced. In this present paper I wish to emphasize the relation between the secretion of total chlorides in gastric juice and the secretion of free hydrochloric acid. Most of the data for this paper were obtained at that time but u...