The Influence of ZnCl2 Activation on Macronutrient NPK Adsorption Simultaneously Using Coconut Shell Biochar for Soil Fertility Improvement

The influence of ZnCl 2  activation on macronutrient Nitrogen, Phosphor, Potassium (NPK) adsorption simultaneously using Coconut Shell Biochar for soil fertility improvement has been conducted.  Biochar formation is carried out at temperature up to 500  o C using variation in the concentration of ZnCl 2  0,5; 1,0; 1,5; 2,0; dan 2,5 M.  The biochar formed was characterized using  Fourier Transform InfraRed  (FTIR)  spectroscopy  and  Surface Area Analyzer  (SAA). Whereas NPK analysis has used the Indonesian standard method (SNI 7763: 2018). Based on this research, it was concluded that the greater the concentration of ZnCl 2  activator, indicated that the higher intensity of the spectra of –OH and –NH 2  at wave number 3400 cm -1  and 1600 cm -1 . It showed that biochar activation was higher and a more active functional group was opened. Increasing the concentration of ZnCl 2  activator has increased Biochar adsorption of NPK macronutrients. The optimum condition for activation of coconut shell Biochar was activation with ZnCl 2  2.5 M. The addition of activated Biochar was increased soil adsorption on NPK macronutrients. Biochar addition had increased Nitrogen (N) adsorption up to 23.53%, Phosphor (P) up to 200%, and Potassium (K) up to 41.24%.