I follow the guides on here for washing spice with sodium carb and activated carbon and then re X but usually end up with around a 50% loss in yield.

The spice I'm washing is not super dirty but usually yellow. Obviously I haven't posted pictures with exact step by step of what I'm doing but I'll give you a brief run down of my last attempt.

Spice was yellow and white mixed together from last re X, so I thought I'd wash it to get it all white.

1. Dissolve spice in hot hexane
2. Add pinch of sodium carb to some warm water
3. Add small amount of that water to hexane and mix
4. Remove water and put in another container
5. Add another small amount of hexane to the water and mix to get any spice left in it
6. Add that hexane to the original hexane
7. Add a pinch of activated carbon to combined hexanes and mix
8. Filter out carbon
9. Pour some more solvent through the filter to get any bits left in the carbon
10. Put solvent in dish. At this point solvent looked very clear
11. Cover and leave out at room temperature for a few hours
12. Put in fridge for a few hours
13. Put in freezer overnight

After all this my spice was still a very light yellow, almost fluorescent and I lost around 50% in yield.

Am I doing something wrong or missing something?

I have never attempted the procedure you are planning to clean up with. One of the best clean ups I've found is a mini A/B with back salting. I am new to the nexus and am not sure how to quote from another thread, but I have copy and pasted the procedure below.


CLEAN UP STEPS
Step 1
In a glass bottle with a thin neck approx 1ltr in size , in this bottle place approx 500ml water with you're choice of acid to get a ph 2-3 as before !

Step 2
place into this acidic water you're naphtha pulls that has been pulled from the basic soup !


Important
Now rock or swirl this gently for as long as it takes to fully exchange the saturated naps to the acidic water
( roughly 10-15 mins ) important pls read below ... !
When mixing the dmt enriched nps with the acidic water the fat content and some minuet plant dust ( depending on how finely powdered the bark ) will seperate in between the two layers and if shaken violently or roughly it can break up the brown fatty substance into smaller pieces which will then get caught up and form a fatty emulsion which will be very hard to break and can trap valuable dmt enriched liquid so please mix cautiously !

Step 3
Now pipette or siphon out all the naphtha along with the brown fatty liquid that sits animated in between the two layers and discard this as it contains the plant fats and oils and no longer contains any alkaloids !!

Now the 500ml acidic water solution contains the dmt !

Step 4
Now get 200ml water add to this 50g of lye and add this to the acidic solution , it will turn white & milky straight away and dmt will crash out of the mix and flout around in the solution so we need to top off the bottle with a futher amount off water but just leave enough room for you're 50ml naphtha to fit !!



Step 5
Now just like with the extraction ....we need to mix and then let the solutions mix and separate upto 4 times with fresh hot naphtha .......now it will be very saturated and will turn white and thick as soon as it hits the cool pipette or syringe ) this is the dmt crashing out at a cooler temp .........now do this at least 4-5 times and this shaking won't cause an emulsion !
You will notice the pulls are crystal clear


You will notice there seems to be a white fatty layer between the water and new solvent , this is normal ! It is a mix of dmt particles and mostly of fat that seems to still make it through the Backsalting stage !
Now with every pull it will get thinner just don't suck any off it up !
Do this until the mix is no longer white or until the mix is not any longer giving any dmt , I usually do about 5x pulls and place all 5 pulls in one precip dish !



Step 6
Now pre evap with a fan or fresh air from a open window blowing air across the dish until half the liquid has evaporated or until naphtha turns milky ( but don't just go off the liquid turning milky as it will turn milky with any cool air blowing over the dish ) so go off the volume



Step 7
Now cover with plastic wrap or with anything that creates a air tight , watertight seal ! Large ziplock bags even if there's no other way and then freeze for 18+ hrs then once you get it out the freezer tip the naphtha of the top then place dish side on then fan dry
(please do this as quick as possible ) , after a couple of hours drying you then can scrape then smoke ! Good luck !

Later pulls can be done and I suggest to do as many pulls as is required until the bark is spent ! But later pulls done singly don't require a defat and this is a good way of seeing if you're bark is still putting out !q

Also I've been not doing any freeze precipes lately to get the most beautiful thick heavy diamond shapes crystals its not very ethical with having to reuse the naps but at least it's not going down the drain so it could be worse ,

Anyway good luck people's , and if there's any questions pls just. Ask !!



I'm pretty sure this clean up with help remove you're impruriries without losing any magic

Hear is what I do, super basic .
Take 20ml Hexane (+ 5ml for the Queen) for each gram of spice.

Pour boiling water into a baking tray , let it cool for a few mins, too hot will pull negative material. I think its about 70 degrees you want.

Place the Hexane in a beaker, standing in the warm water and place the spice in a beaker next to the Hexane.

Take a mini eye dropper thingy, start adding drops of warm Hexane to the spice whilst mixing. As if you want to make milk from powdered milk without any lumps.

Eventually add all the Hexane.

After mixing let it sit for a 5 mins. Take it out of the baking tray and leave for 10 more mins at room temp.

You can leave it to see if all the yellow falls out but some times that doesn't work, I wait 10 mins.

Slowly pour the top layer of Hexane into a glass baking tray. (the yellow slag will sit at the bottom of the beaker)

Leave to cool down to room temp, then into the fridge for a while then into the freezer overnight. I skip the fridge part.

The yellow slag holds untold spice so save it and after a few extractions and washes you can wash the slag.
Hope this helps.

(I can have 8g spice but walk away with 5g or less, white)