Process Of Removing Aluminum From Light Rare Earth Mixed Solution By Naphthenic Acid

In this paper,the mixed light rare earth liquid is used as raw material,and the traditional naphthenic acid aluminum removal process has intermittent production,low processing capacity,low automation,continuous operation,low aluminum rare earth products,low equipment utilization,etc.problem.Through the study on the aluminoxane removal process of mixed light rare earth solution,under the premise of ensuring the quality of rare earth products.Aluminizing behavior of naphthenic acid in a rare earth solution containing cerium after grouping,provide qualified,low aluminum rare earth liquid before the grouping.Through laboratory processes optimizated,the separation of aluminum and rare earths was studied by acidity of the feed liquid,aluminum content of the feed liquid,degree of saponification of naphthenic acid,acidity of the washing liquid,temperature,and organic molar concentration.Finally,the molar concentration of naphthenic acid was determined to be 0.5mol/L,the degree of saponification of naphthenic acid was 0.3 mol/L,the pH of the feed liquid was 1-2,the content of aluminum in the feed liquid was 0.17-0.23 g/L,and the extraction reaction was compared with O:A（Organic phase:Water phase）=1:2,the temperature of the feed liquid is room temperature 20-30℃and the acidity of the washing liquid 0.1 mol/L is the best laboratory conditions.In order to verify its feasibility,expanding the experiment under the process conditions determined by the small test,and the process parameters were further optimized according to the site conditions:the saponification degree was 0.1 mol/L,the acidity of the washing liquid was 0.2 mol/L,and the organic molar concentration was 0.3 mol/L is the most ideal industrial control value,keeping other parameters the same as laboratory process conditions.Flow ratio selection,organic:lye:material liquid:washing liquid:anti-liquid:washing water=100:0.9:210:6.5:2.0:7.5,stable operation after removing aluminum,the remaining liquid index is qualified,Al₂O₃/REO are less than 0.01%The rare earth concentration is greater than 280g/L.Finally,compared with the traditional process,the naphthenic acid aluminum removal process of the mixed light rare earth solution can not only achieve automatic continuous production,reduce the labor intensity of the operator,but also greatly reduce the use of water.And wastewater discharge,while avoiding the use of oxalic acid,to achieve a significant reduction in production costs;compared with the traditional fractionation extraction and aluminum removal process,the types of low-aluminum rare earth products are increased,the utilization-rate of equipment and extensive of process are improved.