C. Vargas
University of Santiago, Chile
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by C. Vargas.
Hydrometallurgy | 2002
Patricio Navarro; C. Vargas; A. Villarroel; Francisco José Alguacil
Abstract The use of ammonium thiosulphate as leaching agent for gold from a flotation concentrate has been studied. The gold content in the concentrate was 95 g/t, whereas the main mineralogical species were chalcopyrite, pyrite, pyrrhotite, tennantite and sphalerite. The experimental variables studied were: (i) Cu(II) concentration (0–6.5 g Cu(II) (added) per liter of leaching solution), (ii) thiosulphate concentration (0.1–0.7 M), (iii) pH (9–10) and (iv) pulp density (10–40%). Best gold dissolution (94%) was obtained at 0.05 M Cu(II), 0.3 M S 2 O 3 2− , pH 10 and 10% pulp density after 15 h, whereas cyanidation gives the same yield but after about 46 h of reaction.
Gold Bulletin | 2006
Patricio Navarro; C. Vargas; Manuel Alonso; Francisco José Alguacil
The adsorption of gold on activated carbon in ammoniacal thiosulfate solution was studied. The variables affecting the adsorption of gold on the carbon included, among others, temperature, concentrations of ammonium hydroxide and thiosulfate, and those of accompanying cations and anions. The apparent activation energy for the adsorption process was estimated to be 19.4 kJ/mol, and this value indicates that the gold adsorption is film diffusion-controlled. It was also found that the rate of initial adsorption rate was fast, when compared to that of the overall adsorption process.
Revista Facultad De Ingenieria-universidad De Antioquia | 2016
Patricio Navarro; C. Vargas; Carlos Ramírez
The physical and chemical properties of a copper leaching solution were quantified and analyzed in presence of high concentrations of chlorine, aluminum and magnesium. The properties tested were the density, viscosity and dissolved oxygen. The effect of the viscosity over time of phase separation in solvent extraction was also evaluated. The concentrations used of chlorine were 20, 30 and 50 g/L, aluminum 7, 15 and 23 g/L and finally the magnesium of 6, 14 and 22 g/L. The temperatures tested were 25, 35 and45 °C. The results showed that the presence of impurities produces a significant impact on the viscosity and only small changes in density. Chlorine is the impurity with less impact, followed by magnesium, and aluminum producing the greatest impact. The temperature increase reduces the impact of these elements. The presence of impurities causes a decrease in dissolved oxygen concentration. In solvent extraction, an increase in viscosity produces longer times of phase separation.
Minerals Engineering | 2004
Patricio Navarro; R. Alvarez; C. Vargas; Francisco José Alguacil
Desalination | 2007
Patricio Navarro; C. Vargas; Manuel Alonso; Francisco José Alguacil
Revista De Metalurgia | 2009
Gerardo Cifuentes; C. Vargas; Jaime Simpson
Revista De Metalurgia | 2005
Patricio Navarro; C. Vargas; R. Alvarez; Francisco José Alguacil
Revista De Metalurgia | 2004
Patricio Navarro; C. Vargas; Eyleen Araya; I. Martin; Francisco José Alguacil
Revista De Metalurgia | 2006
C. Vargas; Patricio Navarro; Eyleen Araya; F. Pávez; Francisco José Alguacil
Revista De Metalurgia | 2006
Patricio Navarro; C. Vargas; V. Reveco; J. Orellana