摘要
以草酸/草酸盐沉淀法除杂是盐湖提锂极具发展前景的提锂工艺之一,但是因加入过量草酸/草酸盐会导致蒸发母液的总有机碳(TOC)过高进而对生产稳定性造成影响,所以需要降低TOC。以某大型化工企业的蒸发母液为原料,系统研究了硼掺杂的金刚石(BDD)电极电化学氧化降低TOC的最佳工艺参数,提出一种经济可行的组合方案。实验结果显示,在反应温度60℃、电流密度70 mA/cm^(2)条件下,BDD电化学氧化24 h可将母液TOC从1550 mg/L降到66.8 mg/L,氧化助剂H2O2的加入对降解效果没有增益作用。基于BDD电化学氧化在8 h内具有可观的TOC去除效果,为了进一步优化所需能耗,提出“XDA-1型大孔树脂吸附(2 BV/h,25℃,动态吸附)+BDD电化学氧化4 h(60℃,70 mA/cm^(2))+C1型活性炭(6 h,25℃,静态吸附)”的方案,可将母液TOC值从1550 mg/L降到52 mg/L。研究成果为实现蒸发母液TOC的高效降解探索出了一条可行的途径,具备显著的实用价值与推广意义。
Using the precipitation method with oxalic acid/oxalates for impurity removal in lithium extraction from salt lakes is a promising technology.However,excessive addition of oxalic acid/oxalates can lead to an elevated total organic carbon(TOC)levels in the evaporation mother liquor,which can adversely affect production stability.Consequently,reducing TOC is crucial.This study systematically investigates the optimal parameters for electrochemical oxidation to reduce TOC using boron-doped diamond(BDD)electrodes,utilizing evaporation mother liquor from a large chemical enterprise as a raw material,and presents a cost-effective combination solution.The experimental results indicated that BDD electrochemical oxidation at a reaction temperature of 60℃and a current density of 70 mA/cm^(2)for 24 hours can reduce the TOC from 1550 mg/L to 66.8 mg/L,with no additional benefit from the oxidant H2O2.Given the significant TOC removal observed within 8 hours,for the purpose of further reducing the energy consumption,a combined strategy is proposed:XDA-1 type macroporous resin adsorption(2 BV/h,25℃,dynamic adsorption)+BDD electrochemical oxidation for 4 hours(60℃,70 mA/cm^(2))+C1 type activated carbon(6 hours,25℃,static adsorption),which can reduce the TOC from 1550 mg/L to 52 mg/L.The research findings offer a feasible pathway for efficient TOC degradation in the evaporation mother liquor,demonstrating significant practical value and potential for widespread application.
作者
何志
赵聪
廖正江
何劲松
肖松林
王诗潇
费飚
张潇迪
唐田
HE Zhi;ZHAO Cong;LIAO Zhengjiang;HE Jinsong;XIAO Songlin;WANG Shixiao;FEI biao;ZHANG Xiaodi;TANG Tian(SCSDN Environmental Technology Co.,Ltd.,Chengdu,611731,China)
出处
《盐湖研究》
2025年第3期64-69,共6页
Journal of Salt Lake Research
关键词
BDD电极
电化学氧化
盐湖提锂
高TOC蒸发母液
工艺参数
BDD electrode
Electrochemical oxidation
Salt lake lithium extraction
High TOC evaporation mother liquor
Process parameters
作者简介
通信作者:何志(1970-),男,高级工程师,主要从事锂电新能源材料产业链清洁生产、节能环保技术的研发和推广。Email:hezhi@sdnenv.com。
