454
I. Thoming et al.
this is definitely a suitable argument for convincing the gold prospectors to treat
their residues.
In order to improve the space-time yield of the electrolysis cell, it is necessary
to increase the surface area of the cathode where the deposition takes place.
Therefore, several configurations of electrochemical reactors have been proposed
(Robertson 1978). Technical feasibility of removing traces of mercury by using
extended surface area electrodes was shown. Robertson et al. (1978) reduced the
level of mercury to below the accepted concentration of 0.01 ppm in waste water
by employing the Swiss-roll cell with a cadmium-coated stainless steel cathode.
The use of graphite felt as an efficient porous electrode for the removal of traces
of mercury ions from aqueous electrolyte solutions was investigated by Oren and
Soffer (1983). Matlosz and Newman (1986) investigated a flow-through porous
electrode, made of reticulated vitreous carbon, for removal of mercury from
contaminated brine.
The final leaching solution should not be discharged, since it contains not only
high salinity but also some remaining soluble mercury species in concentration
not suitable for discharging. The recycling of this solution is advisable, using the
residue treatment process.
Acknowledgements This work was supported by the bilateral Brazilian-German cooperation program,
the International Bureau at GKSS and the Federal Ministry of Education, Scientific Research and
Technology (BMBF).
References
Bailey SM, Churney KL, Nuttall RL (1982) The NBS tables of chemical thermodynamic properties,
selected values for inorganic and CI and C2 organic substances in SI units. J Phys Chern Ref Data II,
Suppl 2
Balej I (1985) Mercury. In: Bard AI, Parsons R, lordan I (eds) Standard Potentials in aqueous
solutions. Marcel Dekker, New York, pp 265~285
Barin I (1993) Thermochemical data of pure substances. VCH, Weinheim
Bromley LA (1973) Thermodynamic properties of strong electrolytes in aqueous solutions. AIChE I 19:
313~320
Hansen H (1958) Constitution of binary alloys. McGraw-Hill, London
Haung HH, Cuentas L (1989) Construction of Eh-pH and other stability diagrams of uranium in a
multicomponent system with a microcomputer. I. Domains of predominance diagrams. Can
Metallurg Q 28. (3) 225~234
Knacke 0, Kubaschewski 0, Hesselmann K (1991) Thermochemical properties of inorganic
substances. Springer, Berlin Heidelberg New York
Lindsay WL (1979) Chemical equilibria in soils. lohn Wiley, New York
Matlosz M, Newman I (1986) Experimental investigation of a porous carbon electrode for the removal
of mercury from contaminated brine. I Electrochem Soc 133:1850~1859
Oren Y, Soffer A (1983) Graphite felt as an efficient porous electrode for impurity removal and
recovery of metals. Electrochim Acta 28:1649~1654
Rastogi A, Tassios D (1980) Estimation of thermodynamic properties of binary aqueous electrolytic
solutions in the range 25~100o C. Ind Eng Chern Process Des Dev 19:477~482
Robertson PM, Scholder B, Theis G, Ibl N (1978) Construction and properties of the Swiss-Roll
electrolysis cell and its application to waste water treatment. Chem Ind (Lond), I luly, pp 459~465
I. Thoming et al.
this is definitely a suitable argument for convincing the gold prospectors to treat
their residues.
In order to improve the space-time yield of the electrolysis cell, it is necessary
to increase the surface area of the cathode where the deposition takes place.
Therefore, several configurations of electrochemical reactors have been proposed
(Robertson 1978). Technical feasibility of removing traces of mercury by using
extended surface area electrodes was shown. Robertson et al. (1978) reduced the
level of mercury to below the accepted concentration of 0.01 ppm in waste water
by employing the Swiss-roll cell with a cadmium-coated stainless steel cathode.
The use of graphite felt as an efficient porous electrode for the removal of traces
of mercury ions from aqueous electrolyte solutions was investigated by Oren and
Soffer (1983). Matlosz and Newman (1986) investigated a flow-through porous
electrode, made of reticulated vitreous carbon, for removal of mercury from
contaminated brine.
The final leaching solution should not be discharged, since it contains not only
high salinity but also some remaining soluble mercury species in concentration
not suitable for discharging. The recycling of this solution is advisable, using the
residue treatment process.
Acknowledgements This work was supported by the bilateral Brazilian-German cooperation program,
the International Bureau at GKSS and the Federal Ministry of Education, Scientific Research and
Technology (BMBF).
References
Bailey SM, Churney KL, Nuttall RL (1982) The NBS tables of chemical thermodynamic properties,
selected values for inorganic and CI and C2 organic substances in SI units. J Phys Chern Ref Data II,
Suppl 2
Balej I (1985) Mercury. In: Bard AI, Parsons R, lordan I (eds) Standard Potentials in aqueous
solutions. Marcel Dekker, New York, pp 265~285
Barin I (1993) Thermochemical data of pure substances. VCH, Weinheim
Bromley LA (1973) Thermodynamic properties of strong electrolytes in aqueous solutions. AIChE I 19:
313~320
Hansen H (1958) Constitution of binary alloys. McGraw-Hill, London
Haung HH, Cuentas L (1989) Construction of Eh-pH and other stability diagrams of uranium in a
multicomponent system with a microcomputer. I. Domains of predominance diagrams. Can
Metallurg Q 28. (3) 225~234
Knacke 0, Kubaschewski 0, Hesselmann K (1991) Thermochemical properties of inorganic
substances. Springer, Berlin Heidelberg New York
Lindsay WL (1979) Chemical equilibria in soils. lohn Wiley, New York
Matlosz M, Newman I (1986) Experimental investigation of a porous carbon electrode for the removal
of mercury from contaminated brine. I Electrochem Soc 133:1850~1859
Oren Y, Soffer A (1983) Graphite felt as an efficient porous electrode for impurity removal and
recovery of metals. Electrochim Acta 28:1649~1654
Rastogi A, Tassios D (1980) Estimation of thermodynamic properties of binary aqueous electrolytic
solutions in the range 25~100o C. Ind Eng Chern Process Des Dev 19:477~482
Robertson PM, Scholder B, Theis G, Ibl N (1978) Construction and properties of the Swiss-Roll
electrolysis cell and its application to waste water treatment. Chem Ind (Lond), I luly, pp 459~465