Environment-Friendly Synthesis of Feldspar-KH2PO4 Complexes by Mechanochemical Reaction

Abstract

Novel materials from Feldspar as clay material and KH2PO4 (KHP) are prepared by grinding in a planetary ball mill in a mechanochemical process, one of the most effective ways to synthesize slow-release fertilizers. In two paths, tests were carried out with (3) weight ratio of Feldspar: KH2PO4 contents, at mill The incorporation of KH2PO4 and the liberation of K+ and PO43− ions into solution were assessed at rotating speeds rangingfrom200to700rpmfortwohours,andatmillingperiodsrangingfrom1h,2h,and3h.Thermalgravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and ion chromatography (IC) were employed to analyze the produced materials. The results confirmed that the mechanochemistry process is a sustainable chemistry method to produce amorphous Feldspars containing KH2PO4. After dispersing Feldspar andKH2PO4 inwaterfor24h,K+ andPO43− ionsweremeasured.Basedonthesestudies,ithasbeendemonstrated that intercalated Feldspar could function as a carrier of K+ ions and release PO3− 4 ions as a slow fertilizer.