Abstract: The present invention discloses a method for preparing Erdite rod-shaped particles for water treatment by utilizing iron-containing waste mud in an underground water plant. In the method, aqueous iron mud is subjected to mechanical dehydration to obtain a first aqueous iron mud; sodium sulfide is added to the first aqueous iron mud to obtain a first mixture, wherein the ratio of the weight of the first aqueous iron mud to the volume of sodium sulfide is between 3% and 15%; water of an equal volume is added to the first mixture, and the obtained solution is heated in an airtight manner to 140° C.-270° C.; centrifugal treatment is performed to obtain a supernatant and a solid, and the solid is subjected to vacuum drying at 40° C.-60° C. for 24 h to obtain Erdite rod-shaped particles.

Abstract: The present invention discloses a method of removing iron ions from a solution containing neodymium, praseodymium, dysprosium and iron, in which glucose is added into an acid solution containing neodymium, praseodymium, dysprosium and iron, at a molar ratio of iron/glucose at 0.2-2, and mixed evenly, and the solution is then hydrothermal treated, and after that an iron-containing precipitate is formed at the bottom, and the residual concentration of iron in the supernatant is less than 20 mg/L, and the retention rate of the rare earth elements is more than 97%.

Abstract: The present invention discloses a method for preparing Erdite rod-shaped particles for water treatment by utilizing iron-containing waste mud in an underground water plant. In the method, aqueous iron mud is subjected to mechanical dehydration to obtain a first aqueous iron mud; sodium sulfide is added to the first aqueous iron mud to obtain a first mixture, wherein the ratio of the weight of the first aqueous iron mud to the volume of sodium sulfide is between 3% and 15%; water of an equal volume is added to the first mixture, and the obtained solution is heated in an airtight manner to 140° C.-270° C.; centrifugal treatment is performed to obtain a supernatant and a solid, and the solid is subjected to vacuum drying at 40° C.-60° C. for 24h to obtain Erdite rod-shaped particles.