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Synthesis of Fine Particles by Precipitation Stripping using Liftrasound and Monitoring of their Morphology

使用 Liftrasound 通过沉淀剥离合成细颗粒并监测其形态

基本信息

批准号：
10555349
负责人：
NIINAE Masakazu
金额：
$ 7.23万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

Solvent extraction is a widely used process for recovery, separation and purification of metals from minerals or other metal-bearing materials. In conventional solvent extraction, metals are stripped from loaded organic phase into an aqueous phase with mineral acids, then recovered in a following step. Recently, applicability of integrating stripping and metal recovery (as powder) into a single process step has been investigated. Therefore, the direct production of metal powder from metal-loaded organic phase is of interest as a new production method of metal powder. In the precipitation stripping, the droplet size and the reaction rate have a significant effect on the precipitate size and morphology In such a system, ultrasound, because of its compression and expansion, can tear the liquid droplets, increasing the contact area between the immiscible organic and aqueous phases through emulsion and dramatically increasing the rate of stripping. In addition to its emulsifying effect, ultrasonic energy further increases precipitation stripping through enbanced agitation and the removal of stagnant liquid near the interface between the organic and aqueous phases. Therefore, we investigated the utilization of ultrasound for the purpose of controlling the size ad morphology of the powders.In the present study, we found that the possibility of controlling the size and morphology of the powders by using ultrasonic energy ; furthermore, the effect of various conditions of organic and aqueous phases, such as metal concentration in an organic phase, stripping agent concentration and acidity in an aqueous phase, on the size and morphology of the powders was also investigated, Also, we investigated the fundamental process of precipitation stripping and the synthesis of mixed oxalate powders for transition metal and rare earth metal.

溶剂萃取是一种广泛使用的从矿物或其他含金属材料中回收、分离和纯化金属的方法。在传统的溶剂萃取中，金属从负载的有机相中用无机酸汽提到水相中，然后在下一步骤中回收。最近，已经研究了将剥离和金属回收（作为粉末）整合到单个工艺步骤中的适用性。因此，从负载金属的有机相直接生产金属粉末作为一种新的金属粉末生产方法是令人感兴趣的。在沉淀反萃取中，液滴尺寸和反应速率对沉淀物的尺寸和形态有显著影响。在这样的体系中，超声波由于其压缩和膨胀，可以撕裂液滴，通过乳化增加不混溶的有机相和水相之间的接触面积，并显著提高反萃取速率。除了其乳化作用外，超声波能量还通过增强搅拌和去除有机相和水相之间界面附近的停滞液体来进一步增加沉淀汽提。因此，我们研究了利用超声来控制粉体的尺寸和形貌，发现利用超声能量控制粉体的尺寸和形貌的可能性;此外，有机相和水相的各种条件，如有机相中的金属浓度，反萃取剂浓度和水相中的酸度，研究了沉淀反萃法的基本工艺以及过渡金属和稀土金属混合草酸盐粉体的合成。