Hi Phaedris,
I have two such scraping tools. As the fumarate is initially quite sticky it's useful to use them to repeatedly scrape each other clean. I used to use razors but I'm sure you know how hard this stuff gets if you don't catch it just in time. The second picture shows the evap dish standing vertically- I try to catch the fumarate at EXACTLY that stage where it can stand vertical without running. The material is still almost liquid beneath the surface but drys very quickly when worked around.
I didn't record the temperature. I'm afraid I didn't keep any 'lab notes' at all
The heat source I used was a commonly available cheap plastic heat-pad designed to keep home-brew warm in order to aid fermentation. It is advertised as maintaining temperature at around 26deg C above ambient so I would imagine temp. of solution to be approx 50deg C. (HDPE jugs were wrapped in bath towel).
The solution was allowed to sit for two months for several reasons- mostly due to work commitments but also I was curious of others' reports of continued yields over an extended period.
Yeah, the yield was good. I think I pretty much exhausted this batch (Pedro re-seller). I imagine also that the material is clean. For third and final recrystallisation the fumarate was dissolved in 100ml of water @ 25deg C. Wiki gives the solubility of fumaric acid as 0.63g per 100 mL so I don't see how I could have more than about half a gram of excess acid in there.
I would caution though ... the d-limonene had soon become 'dirty brown' looking. It appeared as though it had taken in some suspended particles of the base solution. This was removed by pouring the limo through a cotton ball filter several times. After the salting stage, the DMT/fumaric water also had to be filtered and a thick brown sludge was observed clogging up the filter.
I think that most people will not wish to bother with all the cleaning stages involved but I've been off the SNRIs for a couple of months now and I'm getting a bit OCD again
