#TITLE_ALTERNATIVE#

• Main Author: ELEFANI (NIM 13004070) dan WISNU WIJANARKO (NIM 13004005); Pembimbing : Dr. Sanggono Adisasmit, DINDA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/12911
• Institution: Institut Teknologi Bandung

Not all of fertilizers given by plants could be absorbed, while others are being degradated or leached by ground water so they will cause inefficient fertilizing and environmental pollution of N, P, and K. Because of that problem, slow release fertilizer was needed. Slow-release NPK fertilizer nutrition was released gradually and continuously so that it could reduce nutrition losses by leaching.<p>Nowadays, commercial tablet fertilizer use polymer as coating so that the nutrition can be released slowly. Polymer is unbiodegradable compound, so it is needed a biodegradable coating. Clay as coating is semi permeable and biodegradable. 16-gram slow-release NPK fertilizer (12-10-22 ratio) with 3 cm diameter and 1.5 cm thickness coated and uncoated by clay would be made. Tablet fertilizer was analyzed time release in water medium at 25 degrees C. The performance of slow release fertilizer was compared with commercial tablet fertilizer.<p>The result showed that released rate of nitrogen, phosphorus (as P2O5), and potassium (as K2O) which released from clay coated fertilizer were 0,12 ppm/min, 0,2 ppm/ min, and 0,01 ppm/min. The comparison between released rate of coated and uncoated NPK fertilizer were 1:275 for N, 1:158 for P, and 1:109 for K. Based on Trenkel's clasifications of slow release fertilizer, the coated NPK fertizer using clay as coating was not categorized as slow release fertilizer.