Treatment with nitric acid often works. Which metals are you working with?

Some rare earth oxides solve in dilute acid, some in hot acid, some solve better in alkali. Please consult the handbook of chemistry & physics for your particular oxide.

thanks 

i work with this metals Nd2O3, Gd2O3, Yb2O3, Eu2O3.

i try to solve Yb2O3 in HCl with pH

Hi Allouche,

Yb2O3 is normally only soluble in hot dilute acids.  I think you still have unsolvable Yb2O3 in the strong HCl solution. Try hot dilute HCl (pH = 3-5). If that does not work I would try hot dilute HNO3.

Check the handbook for specifics on the other oxides. If you dissolve oxides in dilute acids which are in the pH range 5-7 you might get a clear solution at first. If you let those solutions stand for a while they might get milky due to hydrolization (forming of Me-OH like compounds) or they might react with carbondioxide from the air leading to carbonates being deposited. So use the clear dilute acid solutions as fast as possible.

dear Peter

should i dilute HCl acid?? because i need this concentration in preparation of other catalyst my objectif is doping not only dissolve rare earth oxide..

i check Handbook of Chemistry and Physics 84th Edition i didn't find rare earth oxide??

i think use ultrasonic bath to dissolve this rare earth oxides?? what do you think??

thanks everybody 

In the inorganic part of the handbook you can find all inorganic compounds (including the oxides), their properties and what is the best way to dissolve them.

Dear Allouche

Do you solve the problem at last ? I have come across a similar problem. I want to do ICP tests with my material, however I cant dissolve it. The material consists of ZrO2, Y2O3, Yb2O3, Gd2O3. Especially Yb2O3 and Gd2O3.

Dear Allouche,

Allouche Sidali Please were you able to solve the problem? I also have a similar problem. i have Eu2O3 but i want to make the nitrate, in order to prepare some layered materials.

Thank you in anticipation of your prompt response.

I have try to dilute Y2O3 to acid nitrite. I add 10 g Y2O3 to 20 ml acid nitrite and water. Heat to acid nitrite boiling point (90-92 C). Originally the solution in white color. After reach the boiling point (90 C) the solution become very clear. That means, all the Y2O3 dissolve to acid nitrate. I do believe that, i have completely convert Y2O3 to Y(NO3)3.

Nd2O3 + 6HNO3 = 2Nd(NO3)3 + 3H2O

To Preparation of 100 gm of Neodymium nitrate 38.38 gm of oxide is required.

Most Lanthanide oxides give their nitrates when dissolved in conc. HNO3. Heat to dryness to obtain rare earth nitrate.

thank you to everyone for these clarifications.

See also: https://www.researchgate.net/post/Can_anyone_tell_me_how_to_prepare_Lanthanum_Nitrate_from_Lanthanum_III_oxide https://www.researchgate.net/post/How_to_convert_yttrium_oxide_Y2O3_to_yttrium_nitrate_or_nitride_And_what_safety_measure_to_be_taken_if_mixing_in_HNO3

can you tell me witch laboratory used the nitrate of rare earth in algeria?

Hello Professor, Can I know the process with calculations for Neodymium oxide to Neodymium nitrate conversion?