Recovery of copper from industrial waste solution by cementation on reciprocating horizontal perforated zinc disc

Mass transfer correlation of simultaneous removal by cementation of nickel and cobalt from sulfate industrial solution containing copper

“…The slopes of these plots yield an activation energies of 24 and 60 kJ mol −1 for nickel and cobalt, respectively. Activation energies of these magnitudes are indica- tive that the reaction of nickel is diffusion-controlled and the cobalt deposition is chemically controlled [28][29][30][31][32]. These results are consistent which those found above (the rate of Ni cementation increases with increasing the rotation rate of the elec- trode while the rate of Co cementation is independent of the agitation).…”

Improving the rate of Cu+2 recovery from industrial wastewater using a vertical array of reciprocating perforated zinc discs

“…both diffusion and chemical reaction steps contributed to determining the rate of the reaction, the reaction under the present conditions is partially diffusion controlled. The discrepancy between the present finding and the other cementation studies which conclude that cementation of Cu +2 on Zn is diffusion controlled [9][10][11][12] may be attributed to the strong enhancing effect of the new system of pulsating array of perforated zinc discs compared to other enhancing means such as mechanical stirring and gas sparging. It seems that the turbulences generated by perforated disc pulsation eliminate a considerable part of the mass transfer resistance to the extent that the rate of mass transfer approaches in magnitude the rate of the chemical step.…”

“…Kalantary et al [8] studied the effect of vibratory agitation on the rate of metal deposition during electroplating in a cylindrical cell using perforated disc, the authors reported that vibratory agitation increases the rate of metal deposition by a factor ranging from 3 to 20 depending on the operating conditions. Mubarak et al [9] found that disc reciprocation has increased the rate of cementation of copper on reciprocating horizontal perforated zinc disc by a factor ranging from 2.8 to 5.5 compared to cementation on stagnant disc. Elshazly [10,11] in his investigations for the rate of copper recovery from industrial wastewater by cementation using pulsating zinc cylinders and pulsating vertical parallel plates, found that pulsation has increased the rate of cementation by a factor ranging from 2.5 to 5 and from 2.75 to 4.8, compared to stagnant cylinders and stagnant plates respectively.…”

“…Vertical oscillation was induced to the zinc layers by means of a mechanical vibrator connected to the upper end of the stem. The mechanical vibrator was described by the author in previous investigations [9][10][11][12]. The rate of cementation of copper on zinc was followed by measuring the change in concentration of Cu +2 with time.…”

Electrochemical recovery of silver from waste aqueous Ag(I)/Ag(II) redox mediator solution used in mediated electro oxidation process

“…Metal deposition is an electrochemical process that has been studied extensively and is widely used in the industry for the removal of heavy metal ions [8][9][10][11][12]; the recovery of valuable metal ions from waste and dilute solutions was reviewed by Mubarak et al, Choi and Kim [13,14]. The above processes were also applied to purification of solutions or electrolytes from impurities before electrolysis [15,16].…”