摘要
电解锰行业面临电效低、SeO_(2)添加剂剧毒且沉积产物形貌难控制等问题.为了提高电流效率以降低能耗、改善锰电沉积形貌及降低添加剂SeO_(2)的使用量,本文根据电解锰行业标准,配制MnSO_(4)–(NH_(4))_(2)SO_(4)电解液体系,通过添加聚丙烯酸、甘氨酸、乙二胺四乙酸(EDTA)、葡萄糖酸等分别作辅助添加剂,探究其对锰沉积的影响以降低剧毒性主添加剂SeO_(2)的用量.采用场发射扫描电子显微镜(SEM)、X射线衍射分析(XRD)、恒电流阴极极化曲线测试方法(LSV)等表征手段,研究金属锰沉积形貌、晶体结构、阴极电化学极化行为与添加剂之间的关系.结果表明:四种添加剂均可以促进α-Mn的形成,且最优晶型取向为(330)晶面,其中葡萄糖酸最适宜作为辅助添加剂.当以葡萄糖酸为辅助添加剂,质量浓度为1.84 g·L^(-1)时,阴极电流密度明显提高,降低了阴极极化,产品形貌更加致密光滑.最优条件下,SeO_(2)的质量浓度可由工业上常规用量0.03~0.06 g·L^(-1)降低至0.015 g·L^(-1),电流效率可由70%提高至89.73%,能耗由6500 kW·h·t^(-1)降至4990.58 kW·h·t^(-1).研究结果有望为电解锰行业绿色生产和高效电沉积提供借鉴,有助于推动电解锰行业的可持续发展.
Electrolytic manganese is an important metal material that is widely employed in batteries,electronics,steel,and other fields.However,there are many issues regarding the production process of electrolytic manganese,such as low current efficiency,high-content toxic SeO_(2) additives in the electrolyte,and difficulty in controlling the product morphology.These issues not only impact the production efficiency and quality of electrolytic manganese but also result in severe environmental pollution.To address these issues,a MnSO_(4)-(NH_(4))_(2)SO_(4) electrolyte system was prepared based on the electrolytic manganese industry standard.The effects of polyacrylic acid,glycine,ethylenediaminetetraacetic acid(EDTA),and gluconic acid were explored as auxiliary additives under neutral electrolysis conditions to lower the SeO_(2) content,which is a highly toxic main additive.The effects of the different additives on the metal manganese morphology,crystal structure,and cathodic electrochemical polarization behavior were examined by field-emission scanning electron microscopy,X-ray diffraction,and constant current cathodic polarization curve tests.The findings reveal that the main orientation of the metal manganese crystal form deposited by the four auxiliary additives is the(330)crystal plane,and all of them can promote the formation ofα-Mn,enhance the electrolysis efficiency,and lower the energy consumption.In particular,the optimized amount of polyacrylic acid of 0.08 g·L^(-1) contributes to an energy consumption of 5735.34 kW·h·t^(-1).Correspondingly,the addition of 10 g·L^(-1) glycine is the most favorable amount,leading to an energy consumption of 5518.56 kW·h·t^(-1).For EDTA,the lowest energy consumption of 5168.26 kW·h·t^(-1) is measured at an added amount of 0.5 g·L^(-1).Note that among the four investigated candidates,gluconic acid is the most favorable auxiliary additive,contributing to the increased cathode current density and reduced cathodic polarization as well as denser metal manganese products.Moreover,gluconic acid addition can lower the concentration of toxic SeO_(2) from 0.03–0.06 to 0.015 g·L^(-1),significantly increase the cathode current density,reduce the cathodic polarization,and result in a more dense and smooth product morphology,with the current efficiency being increased from approximately 70%to 89.73%and energy consumption being reduced from 6500 to 4990.58 kW·h·t^(-1) at the same time.Gluconic acid,as the auxiliary additive,not only contributes to the best electrolysis indexes for electrolytic manganese but also facilitates the formation of metal manganese with the most desirable crystal structure.This work offers novel insights into the environmentally friendly production and cheap electrodeposition of metal manganese for the electrolytic manganese industry.
作者
迟晓鹏
张瑞莹
翁威
苏国晖
谭文
衷水平
CHI Xiaopeng;ZHANG Ruiying;WENG Wei;SU Guohui;TAN Wen;ZHONG Shuiping(Zijin School of Geology and Mining,Fuzhou University,Fuzhou,350108,China;Fujian Provincial Key Laboratory of Green Extraction and High-value Utilization of New Energy Metals,Fuzhou,350108,China;Zijin Mining Group Co.,Ltd.,Shanghang 364200,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2024年第5期835-843,共9页
Chinese Journal of Engineering
基金
国家重点研发计划资助项目(2022YFC3900804)
国家自然科学基金面上资助项目(52274349)
福建省自然科学基金资助项目(2023J05024)。
关键词
电解锰
添加剂
有机物
电流效率
极化行为
electrolytic manganese
additive
organic matter
current efficiency
polarization behavior
