You have to give more information if you want us to help properly..
Is mimosa from reputed supplier? How much mimosa? A/B or STB? If A/B, how many boils and for how long? Is solution jet black when adding base? Do you have more info on your naphtha (MSDS or other more detailed info on content)? How much naphtha per pull? Did you do many thorough cycles of mixing/letting stand before pulling the naphtha each time? How much heat to evap? Nothing = literally nothing or small amounts of goo?
Is mimosa from reputed supplier? How much mimosa? A/B or STB? If A/B, how many boils and for how long? Is solution jet black when adding base? Do you have more info on your naphtha (MSDS or other more detailed info on content)? How much naphtha per pull? Did you do many thorough cycles of mixing/letting stand before pulling the naphtha each time? How much heat to evap? Nothing = literally nothing or small amounts of goo?