R2: Crystal structure, crystal chemistry, physical properties of minerals, crystal growth and applied mineralogy

[R2-12] Mineralogical property of a silica potassium fertilizer, “Keisankari” and its dissolution process in soil

*Hiroaki Ohfuji¹, Hiroki Takeuchi², Yo Toma³, Tomoji Hanyu² (1. Tohoku Univ. Sci., 2. Kaihatsuhiryou Co Ltd., 3. Hokkaido Univ. Agr.)

Keywords:Silica potassium fertilizer, Kaliophilite, Akermanite, Dissolution

In this study, we studied the mineralogical property of a silica potassium fertilizer, “Keisankari” composed of a mixture of kaliophilite and akermanite, and its dissolution process in soil by means of XRD and electron microscopy. Detailed SEM-EDS observation of Keisankari samples collected from the soil in the cultivation experiments suggests that the dissolution of akermanite proceeds faster and would complete in the early stage of the cultivation period, while that of kaliophilite is much slower, supplying nutrients to soil for a longer period.