*2.3. Lauric Acid Coating of Biochar*

The biochar surface was modified by taking 24 g biochar, adding 2.4 g SA-CC and 2.4 g lauric acid, and dry milling this mixture with an SFM-1 (model QM-3SP2) planetary ball mill (MTI Corporation, Richmond, CA, USA). The optimum quantity of lauric acid to use was a matter of investigation and is described in Section 3.2. The milling media used was yttrium-stabilized zirconia spheres (3 mm diameter) supplied by the Inframat Corporation (Manchester, CT, USA). A 50:1 weight ratio of milling media:biochar was used with 500 mL capacity stainless steel jars and lids. Ball milling was done at 500 rpm for 30 min, the samples decelerated to zero rpm and rested for 6 min, then were increased to 500 rpm for 30 min in the opposite direction.
