TY - THES N1 - Priyagung Dhemi Widiakongko, M. Sc. ID - digilib71796 UR - https://digilib.uin-suka.ac.id/id/eprint/71796/ A1 - Riska Diani, NIM.: 21106030055 Y1 - 2025/06/05/ N2 - Slow release fertilizer has a slow release mechanism where micro and macronutrients will be released gradually according to plant needs so that nutrients that are not absorbed by plants do not cause residue or side waste from fertilization into the environment. This study aims to determine the characteristics of the constituent groups, surface area, pore width, and pore volume of natural zeolite and synthetic zeolite as a slow release fertilizer matrix. In addition, this study also aims to determine the mechanism of Feł? release and the effect of Feł? concentration on the zeolite-chitosan composite system on the absorption and release of Feł?. This study was conducted in 4 stages, namely the synthesis of a slow release fertilizer matrix in the form of synthetic zeolite, characterization of the slow release fertilizer matrix, manufacture of slow release fertilizer composites and adsorption and desorption tests of slow release fertilizer composites. The results obtained are that the infrared spectrum of natural zeolite shows absorption peaks at 437, 465, 694, 778, 796, 1039, 3435, and 3580 cm?ą, while synthetic zeolite at 433, 459, 662, 687, 994, 1104, 1653, and 3473 cm?ą. Synthetic zeolite has a higher surface area, pore volume, and porosity than natural zeolite, making it more effective as a slow-release fertilizer matrix. The most stable release of Feł? occurs at a concentration of 40 ppm, and the higher the concentration of Feł? in the composite, the greater the absorption and release capacity. PB - UIN SUNAN KALIJAGA YOGYAKARTA KW - Pupuk Slow Release KW - Zeolit KW - Feł? M1 - skripsi TI - PENGARUH VARIASI KONSENTRASI BESI (Fe3+) DALAM KOMPOSIT ZEOLIT ALAM-KITOSAN DAN ZEOLIT SINTESIS-KITOSAN TERHADAP PERFORMANYA SEBAGAI PUPUK SLOW RELEASE AV - restricted EP - 96 ER -