According to a trial in nicaragua, from memory (google it), 25%-50% salt solution; soak the charcoal (which is crushed to the point of not filtering too much th

According to a trial in nicaragua, from memory (google it), 25%-50% salt solution; soak the charcoal (which is crushed to the point of not filtering too much through whatever filtering mechanism you're going to use) for 24 hours; let dry in the sun (plenty of sun in their trial, i assume baking is the same). (Can't remember if they rinsed).