Red mud is an important secondary resource for scandium production.The red mud leaching solution containing scandium in this study was derived from environmentally friendly ammonium sulfate roasting and water leaching...Red mud is an important secondary resource for scandium production.The red mud leaching solution containing scandium in this study was derived from environmentally friendly ammonium sulfate roasting and water leaching process.A synergistic extraction with a mixture of di(2-ethylhexyl)phosphate acid(D2EHPA)and tributyl phosphate(TBP)for recovery of scandium from red mud leaching solution is proposed.The effects of D2EHPA concentration,H_(2)SO_(4)concentration,rare earth elements,dosage of TBP,phase ratio(A/O),contact time and H_(2)O_(2)concentration on scandium extraction were investigated.The results show that more than 99%scandium is extracted under the optimal conditions while Fe,Al,Ti,Ca and rare earth elements(Ce,Y,La,Nd,Er,etc.)are hardly extracted.The stripping efficiency of Sc reaches above 92.37%under the optimal stripping conditions of 5 mol/L NaOH with an A/O of 1 at 90℃for 30 min.The proposed technology could provide an effective method for extraction of scandium from red mud leaching solution.展开更多
直接焚烧核燃料后处理过程中产生的磷酸三丁酯(TBP)和煤油(OK)有机废液会产生磷酸,会对设备造成一定程度的腐蚀,因此在采用热解焚烧工艺处理该废液时,需掺入合适比例的中和剂和表面活性剂等添加剂,将废液配制成均匀稳定的悬浮液。中和...直接焚烧核燃料后处理过程中产生的磷酸三丁酯(TBP)和煤油(OK)有机废液会产生磷酸,会对设备造成一定程度的腐蚀,因此在采用热解焚烧工艺处理该废液时,需掺入合适比例的中和剂和表面活性剂等添加剂,将废液配制成均匀稳定的悬浮液。中和剂在热解过程中可以固定P2O5,避免磷酸生成后对设备的腐蚀。本文通过不同单因素实验研究以Ca(OH)_(2)和Mg(OH)_(2)为中和剂对配制成的TBP/OK悬浮液性能的影响,为后处理厂热解焚烧系统提供新的悬浮液配方思路。试验结果显示:当TBP含量为30%和60%时,Mg(OH)_(2)在相同TBP含量下配制成的悬浮液的最终表面黏度远大于Ca(OH)_(2),Mg(OH)_(2)和Ca(OH)_(2)在30%TBP时的最终表面黏度分别为90.36 m Pa·s和43.42 mPa·s,在60%TBP时的最终表面黏度分别为95.24 m Pa·s和75.09 m Pa·s,同时Mg(OH)_(2)的乳化速度明显优于Ca(OH)_(2),并具有更好的流动性。以Mg(OH)_(2)为中和剂的悬浮液在不同核素和DBP含量下整体稳定性更好。展开更多
基金Project supported by the National Natural Science Foundation of China(52064002)Guangxi Zhuang Autonomous Region Administration for Market Regulation(GSJKJZC2022-9)。
文摘Red mud is an important secondary resource for scandium production.The red mud leaching solution containing scandium in this study was derived from environmentally friendly ammonium sulfate roasting and water leaching process.A synergistic extraction with a mixture of di(2-ethylhexyl)phosphate acid(D2EHPA)and tributyl phosphate(TBP)for recovery of scandium from red mud leaching solution is proposed.The effects of D2EHPA concentration,H_(2)SO_(4)concentration,rare earth elements,dosage of TBP,phase ratio(A/O),contact time and H_(2)O_(2)concentration on scandium extraction were investigated.The results show that more than 99%scandium is extracted under the optimal conditions while Fe,Al,Ti,Ca and rare earth elements(Ce,Y,La,Nd,Er,etc.)are hardly extracted.The stripping efficiency of Sc reaches above 92.37%under the optimal stripping conditions of 5 mol/L NaOH with an A/O of 1 at 90℃for 30 min.The proposed technology could provide an effective method for extraction of scandium from red mud leaching solution.
文摘直接焚烧核燃料后处理过程中产生的磷酸三丁酯(TBP)和煤油(OK)有机废液会产生磷酸,会对设备造成一定程度的腐蚀,因此在采用热解焚烧工艺处理该废液时,需掺入合适比例的中和剂和表面活性剂等添加剂,将废液配制成均匀稳定的悬浮液。中和剂在热解过程中可以固定P2O5,避免磷酸生成后对设备的腐蚀。本文通过不同单因素实验研究以Ca(OH)_(2)和Mg(OH)_(2)为中和剂对配制成的TBP/OK悬浮液性能的影响,为后处理厂热解焚烧系统提供新的悬浮液配方思路。试验结果显示:当TBP含量为30%和60%时,Mg(OH)_(2)在相同TBP含量下配制成的悬浮液的最终表面黏度远大于Ca(OH)_(2),Mg(OH)_(2)和Ca(OH)_(2)在30%TBP时的最终表面黏度分别为90.36 m Pa·s和43.42 mPa·s,在60%TBP时的最终表面黏度分别为95.24 m Pa·s和75.09 m Pa·s,同时Mg(OH)_(2)的乳化速度明显优于Ca(OH)_(2),并具有更好的流动性。以Mg(OH)_(2)为中和剂的悬浮液在不同核素和DBP含量下整体稳定性更好。
