摘要
风化壳淋积型稀土矿中富含中重稀土,是中国十分重要的矿产资源,在国际市场上也具有很强的竞争力。但在稀土原地浸出过程中存在浸取剂渗透速度慢的问题,导致稀土的回收率降低,因此迫切需要提高浸取剂溶液在矿体中的浸取渗透能力。本文选用腐殖酸为助浸剂,研究腐殖酸复配硫酸铵对风化壳淋积型稀土矿浸取渗透过程的影响,并通过黏土表面吸附水层厚度和黏附功的分析探究腐殖酸复配硫酸铵浸取稀土矿时的协同增效机制。结果表明,腐殖酸复配硫酸铵的最佳浸取条件为腐殖酸复配浓度0.2 g·L^(-1),pH=6.5,装矿高度为20 cm,此时浸取剂的渗透速度为5.02×10^(-3) cm·min^(-1)。加入腐殖酸后,黏土矿物表面的吸附水层厚度减小,当腐殖酸浓度为0.2 g·L^(-1),吸附水层厚度到达最小值,而吸附水层厚度越小,水化作用越弱,渗透液更易渗透进入颗粒内部。复配溶液的黏附功及黏附功降低因子均随腐殖酸浓度的增大而减小,当腐殖酸浓度为0.2 g·L^(-1)时达到最小值,黏附功及黏附功降低因子越小,渗透系数越大,对稀土的浸出越有利。
Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earths,and are very important mineral resources in China,which also have a strong competitiveness in the international market.However,there exists a problem of slowseepage velocity of leaching agent during in situ leaching of rare earths,which can lead to a low recovery of rare earths.Therefore,it is urgent to improve the seepage velocity of leaching agent in the ore body.In this paper,humic acid was chosen as leaching aid to study the effect of humic acid compounded with ammonium sulfate on the seepage process of leaching rare earth.The synergistic mechanism of humic acid compounded with ammonium sulfate was investigated by analyzing the adhesion work and the thickness of adsorbed water layer on the clay surface.The results show that the optimal leaching conditions for humic acid compounded with ammonium sulfate are as follows:humic acid concentration of 0.2 g·L^(-1),pH=6.5,and loading height of 20 cm,at which time the seepage velocity of leaching agent is 5.02×10^(-3) cm·min^(-1).After adding humic acid,the thickness of adsorbed water layer on clay surface decreased,and the thickness of adsorbed water layer reached the minimum value when the concentration of humic acid is 0.2 g·L^(-1).The smaller the thickness of the adsorbed water layer is,the weaker the hydration is.And it is easier for the leaching agent to permeate into the interior of the particles.Both the adhesion work and the adhesion work reduction factor of the compounded solutions decrease with the increase of humic acid concentration.The minimum value is reached when the humic acid concentration is 0.2 g·L^(-1).The smaller the adhesion work and the adhesion work reduction factor are,the larger the permeability coefficient is,which is more beneficial to the leaching of rare earths.
作者
周芳
张丹丹
马晨伟
董世鼎
张瞿天
池汝安
Zhou Fang;Zhang Dandan;Ma Chenwei;Dong Shiding;Zhang Qutian;Chi Ruan(School of Resources and Safety Engineering,Wuhan Institute of Technology,Wuhan 430000,China;Hubei Three Gorges Laboratory,Key Laboratory for Green Chemical Process of Ministry of Education,Yichang 443000,China)
出处
《中国稀土学报》
北大核心
2025年第6期1340-1352,共13页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金面上项目(52274266,22078252)
武汉工程大学研究生教育创新基金(CX2023175)资助。
关键词
腐殖酸
风化壳淋积型稀土矿
渗透速度
吸附水层厚度
黏附功
humic acid
weathered crust elution-deposited rare earth ore
seepage velocity
thickness of absorbed water layer
adhesion work
