Chitosan coated mesoporous nano-silica gel as a soil amendment material
S. Hasan, A. Vats, R. Shende, T. Ghosh
South Dakota School of Mines & Technology, US
Keywords: chitosan, silica gel, mesoporous, soil amendment
Abstract:The active soil amendment in certain geographical areas often demands retention of higher moisture content in order to maintain physical conditions of the soil for crop production, and thus, immobilization of top soil nutrients onto the material is essential. Therefore, effective soil amendment using conventional techniques usually require a large supply of nutrients to maintain suitable soil conditions. Several researchers have been investigated different organic materials and inorganic polymers as water manageable material for soil amendment with some success. In this present work, chitosan coated hybrid organic-inorganic mesoporous silica gel was synthesized as a potential soil amendment material. The performance of this material for higher moisture retention for a relatively longer period of time and nutrient adsorption capacity has been investigated. The main objective of this work was to prepare a mesoporous material with 30-50% moisture and nutrient adsorption capacity at the temperature range of 25-50°C. It is expected that the adsorbed moisture or nutrient will retain in the mesopores of the material and release slowly at adverse environmental conditions. In the synthesis approach, modified sol-gel technique was used to prepare mesoporous silica gel using tetramethyl orthosilicate (TMOS), Pluronic-123, and methanol as precursor, surfactant, and continuous phase, respectively, whereas, chitosan used as a binder. Chitosan is a non-toxic, biodegradable, and biocompatible cationic polymer. The approach used to prepare hybrid organic-inorganic nanosilica gel relies on the principle of nucleation, growth, and subsequent aggregation of nanoparticles in solution-phase.