The anthraquinone is 80%, in a widely available garden product, though this lot is at least ten years old, but has been sealed the entire time.
Solubilty of anthroquinone is <100mg/100mL in water at 23°C
I haven't been able to find solubility data for anthraquinone in other solvents, so I'm still searching for the right solvent.
The anthraquinone is mixed with anticaking agent(s) insoluble in ethanol or dichloromethane, which is easily filtered out with vacuum.
Results so far:
solubility 1.3g per 100g dichloromethane @ 25°C
Tried to dissolve and then recrystallize from ethanol, which was weird; some nice beige crystals crashed out during filtering, and a short stay in the fridge had about a gram of crystals collected from 50g of ethanol, but reducing the volume to about half by evaporation failed to produce any more crystals.
Adding water to the ethanolic solution caused some crystallization, but it was so rapid that crystals formed are so small they slip right through filter paper.
I've scoured the net for information on anthraquinone, but can't seem to find any solubility data. If anyone has any info regarding solubility in any solvent I'd be interested.
I'll keep working till I've got the requisite 30g of nice beige crystals required for a 1/10 scale of this (https://www.thevespiary.org/rhodium/Rhodium/chemistry/wacker.benzo-meoh.html)
(https://www.thevespiary.org/rhodium/Rhodium/chemistry/wacker.benzo-meoh.html).