Independent Study Cs-Gluconate Prodecure

Cesium -gluconate Preparation

Add 35 mL of stock CsOH to a clean beaker, while the solution is stirring add gluconic acid until the pH is 7.2, this will be around 65-95 mL and will take a while to stabilize ( this step is an exothermic reaction and you will be able to feel the beaker warm up) the solution will be light brown

Evaporate to approx. half of the total basic volume

Add methanol p.A.(~50-60 mL)slowly while stirring until you can see crystallization(they look like stringy clumps falling to the bottom)

Let it sit overnight at around 4 degrees C / put it in the fridge

Crystals should be white and about ¼ inch thick on the bottom and side of beaker. Use the ground frit to separate as much of the saline as possible from the crystals

Transfer crystals to a 600 mL beaker and clean the frit filter out, dissolve the crystals with as little H2O as possible ~ 30 mL ( solution should turn light brown)

Add 2 spatulas of activated carbon, stir and heat to 80 degrees C

Filter immediately with the filter for activated carbon, the filtered solution should be light brown again

Pour the filtered solution into a clean beaker and add methanol p.A. (~35 mL) slowly while stirring until you can see crystallization( this time it will take less methanol to crystalize)

Overnight at 4 degrees C

Use frit filter to separate crystals from saline

Transfer crystals to a 600 mL beaker and clean the frit filter out, dissolve the crystals with as little H2O as possible ~ 20 mL ( solution should turn light yellow/clear)

Again add methanol p.A. (~30 mL) slowly while stirring until crystallization

Overnight at 4 degrees C

Use frit filter to separate crystals from the saline

One may repeat this procedure once, but by now Cs-gluconate crystals of sufficient quality and bright white color should be obtained

If the solution before you add methanol is yellowish then do another round of precipitation. If the solution is more clear and barely yellow then go ahead to the drying process

To dry the precipitate put the Cs-Gluconate in a 10 cm petri dish, (weight the dish before) and put the dish in an exsiccator with the dish top slightly ajar

When the precipitate is fully dried take a mortar and pestle and crush the precipitate until it looks like flour

Now weigh the precipitate and record it on the petri dish