Engineering Commons^™

The Effect Of Mass Transport On Deposit Quality In Copper Electrowinning, Joseph Bauer

Doctoral Dissertations

"Roughness and nodulation of copper electrodeposits depend strongly on mass transfer conditions of copper ions to the electrode surface. Mass transfer properties in electrowinning electrolytes were first characterized. The effective diffusivity of cupric ion was measured with a rotating disk electrode in CuSO₄-H₂SO₄ electrolytes at temperatures relevant to electrowinning, with and without additives. Adding 20 mg L^-1 of chloride ion increased the measured diffusion coefficient, but commercial smoothing additives had little effect. An empirical formula to predict cupric diffusivity was generated for later use in mass transport modeling.

Boundary layer thickness information for commercial …

Studying The Effects Of New Additive Materials For The Improvement Of The Capacity And Cycle Life Performance Of The Lead-Acid Battery, Julian Kosacki

Doctoral Dissertations

"Lead-acid batteries are an established technology with nearly 99% recyclability; however, lead-acid batteries produce only 40% of their theoretical capacity due to poor active mass utilization and PbSO4 pore blockage, and the longevity of the batteries is hampered by secondary reactions during the cycle life such as corrosion and gassing.

Lead-acid batteries were investigated and improved through several different approaches: an alternative electrolyte to mitigate secondary reactions, graphite additives to improve positive active mass (PAM) utilization, and dispersant additives to help the industrial pasting process.

The thermodynamics and chemical reactions of a commercial electrolyte replacement called Tydrolyte^TM were investigated …