Your handy guide to charcoal, biochar, and activated charcoal
Step 1: Make charcoal. Then powder charcoal by smashing with a hammer or using mortar and pestle. Step 2: Be careful, this step generates heat. In a STAINLESS STEEL (not aluminum) bowl; Make a 25% solution of calcium chloride with water, at a 1:3 ratio. If you have 600 ml of water you want 200 grams of calcium chloride.