{"id":{"repo_id":"must-thes","oai_identifier":"oai:scholarsmine.mst.edu:doctoral_dissertations-3775"},"canonical_url":"https://search.dev.ndltd.org/etd/must-thes/oai:scholarsmine.mst.edu:doctoral_dissertations-3775","repository":{"repo_id":"must-thes","name":"Missouri University of Science and Technology","base_url":"https://scholarsmine.mst.edu/do/oai/"},"display":{"title":"Improving base metal electrowinning","abstract":"<p>\"In zinc electrowinning, Mn oxidizes to form MnO<sub>2</sub> on Pb-Ag anodes, cell walls and pipes. MnO<sub>2</sub> reduces anode corrosion but also leads to short circuits and maintenance issues. MnO<sub>2</sub> is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl<sup>-</sup> ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl<sup>-</sup> ratios at or above 11:1 contained some &gamma;-MnO<sub>2</sub> while scales formed with ratios less than 11:1 did not.</p><p>In copper electrowinning, the effects of temperature, power outages and concentrations of cobalt and manganese on anode corrosion and current efficiency have not been well investigated. Benchscale tests were used to investigate these effects. Anode corrosion in all experiments was minimal probably due to the presence of at least 150 mg/L Co in each electrolyte. Cathode current efficiency typically ranged between 90 and 95% for the experiments. The range of power outage, temperature and concentrations of Mn and Co tested did not produce a significant effect on current efficiency.</p><p>Anode potential estimation equations for industrial tankhouse operations where cobalt is added after solvent extraction and where cobalt concentration is naturally high due to the ores being processed were developed using lab scale tests. These models have been combined with other reported equations to calculate the energy consumption of electrowinning systems for Pb-Ca-Sn anodes in synthetic sulfuric acid electrolytes\"--Abstract, page iv.</p>","abstract_html":"&lt;p&gt;&quot;In zinc electrowinning, Mn oxidizes to form MnO&lt;sub&gt;2&lt;/sub&gt; on Pb-Ag anodes, cell walls and pipes. MnO&lt;sub&gt;2&lt;/sub&gt; reduces anode corrosion but also leads to short circuits and maintenance issues. MnO&lt;sub&gt;2&lt;/sub&gt; is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl&lt;sup&gt;-&lt;/sup&gt; ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl&lt;sup&gt;-&lt;/sup&gt; ratios at or above 11:1 contained some &amp;gamma;-MnO&lt;sub&gt;2&lt;/sub&gt; while scales formed with ratios less than 11:1 did not.&lt;/p&gt;&lt;p&gt;In copper electrowinning, the effects of temperature, power outages and concentrations of cobalt and manganese on anode corrosion and current efficiency have not been well investigated. Benchscale tests were used to investigate these effects. Anode corrosion in all experiments was minimal probably due to the presence of at least 150 mg/L Co in each electrolyte. Cathode current efficiency typically ranged between 90 and 95% for the experiments. The range of power outage, temperature and concentrations of Mn and Co tested did not produce a significant effect on current efficiency.&lt;/p&gt;&lt;p&gt;Anode potential estimation equations for industrial tankhouse operations where cobalt is added after solvent extraction and where cobalt concentration is naturally high due to the ores being processed were developed using lab scale tests. These models have been combined with other reported equations to calculate the energy consumption of electrowinning systems for Pb-Ca-Sn anodes in synthetic sulfuric acid electrolytes&quot;--Abstract, page iv.&lt;/p&gt;","abstract_has_math":false,"creators":["Abbey, Charles Ebenezer"],"institution":"Missouri University of Science and Technology","degree_name":"Ph. D. in Materials Science and Engineering","degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T03:18:26Z","subjects":["Anode corrosion","Anode potential","Anode scale","Copper","Energy optimization","Zinc","Materials Science and Engineering","Mining Engineering"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsmine.mst.edu/doctoral_dissertations/2770","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Abbey, Charles Ebenezer"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:type","label":"Dc Type","values":["Dissertation - Open Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph. D. in Materials Science and Engineering"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Missouri University of Science and Technology"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Anode corrosion","Anode potential","Anode scale","Copper","Energy optimization","Zinc","Materials Science and Engineering","Mining Engineering"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsmine.mst.edu/doctoral_dissertations/2770"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["<p>\"In zinc electrowinning, Mn oxidizes to form MnO<sub>2</sub> on Pb-Ag anodes, cell walls and pipes. MnO<sub>2</sub> reduces anode corrosion but also leads to short circuits and maintenance issues. MnO<sub>2</sub> is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl<sup>-</sup> ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl<sup>-</sup> ratios at or above 11:1 contained some &gamma;-MnO<sub>2</sub> while scales formed with ratios less than 11:1 did not.</p><p>In copper electrowinning, the effects of temperature, power outages and concentrations of cobalt and manganese on anode corrosion and current efficiency have not been well investigated. Benchscale tests were used to investigate these effects. Anode corrosion in all experiments was minimal probably due to the presence of at least 150 mg/L Co in each electrolyte. Cathode current efficiency typically ranged between 90 and 95% for the experiments. The range of power outage, temperature and concentrations of Mn and Co tested did not produce a significant effect on current efficiency.</p><p>Anode potential estimation equations for industrial tankhouse operations where cobalt is added after solvent extraction and where cobalt concentration is naturally high due to the ores being processed were developed using lab scale tests. These models have been combined with other reported equations to calculate the energy consumption of electrowinning systems for Pb-Ca-Sn anodes in synthetic sulfuric acid electrolytes\"--Abstract, page iv.</p>"]},{"key":"dc:title","label":"Title","values":["Improving base metal electrowinning"]}]}],"canonical_facts":{"dc:creator":["Abbey, Charles Ebenezer"],"dc:description.abstract":["<p>\"In zinc electrowinning, Mn oxidizes to form MnO<sub>2</sub> on Pb-Ag anodes, cell walls and pipes. MnO<sub>2</sub> reduces anode corrosion but also leads to short circuits and maintenance issues. MnO<sub>2</sub> is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl<sup>-</sup> ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl<sup>-</sup> ratios at or above 11:1 contained some &gamma;-MnO<sub>2</sub> while scales formed with ratios less than 11:1 did not.</p><p>In copper electrowinning, the effects of temperature, power outages and concentrations of cobalt and manganese on anode corrosion and current efficiency have not been well investigated. Benchscale tests were used to investigate these effects. Anode corrosion in all experiments was minimal probably due to the presence of at least 150 mg/L Co in each electrolyte. Cathode current efficiency typically ranged between 90 and 95% for the experiments. The range of power outage, temperature and concentrations of Mn and Co tested did not produce a significant effect on current efficiency.</p><p>Anode potential estimation equations for industrial tankhouse operations where cobalt is added after solvent extraction and where cobalt concentration is naturally high due to the ores being processed were developed using lab scale tests. These models have been combined with other reported equations to calculate the energy consumption of electrowinning systems for Pb-Ca-Sn anodes in synthetic sulfuric acid electrolytes\"--Abstract, page iv.</p>"],"dc:identifier":["https://scholarsmine.mst.edu/doctoral_dissertations/2770"],"dc:subject":["Anode corrosion","Anode potential","Anode scale","Copper","Energy optimization","Zinc","Materials Science and Engineering","Mining Engineering"],"dc:title":["Improving base metal electrowinning"],"dc:type":["Dissertation - Open Access"],"thesis:degree_name":["Ph. D. in Materials Science and Engineering"],"thesis:institution_name":["Missouri University of Science and Technology"]},"updated_at":"2026-07-24T03:18:26Z"}