He,
How much naphtha did you use per pull? and 1,5 kilo is really excessive.
The best thing to do is freeze x everything then do a re-extraction if the product is not clean enough.
For a re-extraction just dissolve all your product in vinegar then re-base (you don't need that much lye

) and then re-pull with naphtha.
And by the way, why do kilo extractions. Your product is illegal when purified (you should end up with 15 grams or more, almost a lifetime supply !) in MRHB state its just some natural dye you have laying around.
Good luck,
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