Production of activated biochar from coconut fiber for the removal of organic compounds from phenolic

Abstract The biochar is characterized by low surface area and, in order to their use as adsorbent it is possible to use the activation process that allows to liberate and to increase the pores of the surface, increasing its sorption capacity. In the present work the activation of the biochar produced in the pyrolysis of agroindustrial residue (fiber) of the green coconut was studied, being done with sodium carbonate (Na 2 CO 3 ) at high temperature. Biochar (BC) and activated biochar (ABC) were characterized and ABC was tested for use in the extraction of organic compounds present in the phenolic liquor, produced during the same pyrolysis process. The determination of the textural characteristics was done by N 2 adsorption-desorption isotherms, obtaining an area of 1130 m 2  g −1 for the ABC, being superior to the area of commercial activated coals, with a total volume of pores of 0.55 cm 3  g −1 . For the solid phase extraction (SPE) test, 500 mg of ABC were used in cartridges (equal to the commercial ones) obtaining a retention of about 100% of the organic compounds pre-existing in the sample, demonstrating the high adsorptive capacity of the activated biochar produced in this work. Desorption, as expected, had a lower performance than adsorption, being improved using ultrasonic bath, reaching values of the order of 40% recovery.