Synthesis of EPAN and applications in the encapsulation of potassium humate

Abstract

Abstract This article provides information on the synthesis of esterified derivatives of hydrolyzed polyacrylonitrile (EPAN) based on the polymer waste “Nitron” for use as an encapsulating reagent. The elemental and structural compositions of potassium humate and the organic polymer were determined using a scanning electron microscope (Jeol JSM-6490l V) and an IR Fourier spectrometer (Zhimadzu IR Prestige-21). A method is presented for determining the strength of the encapsulated granules of potassium humates using an IPG-1M device and a TAXTplus texture analyzer (Stable Microsystems). The scientific novelty of the article lies in the synthesis of EPAN from “Nitron” polymer waste using sodium hydroxide in the presence of ethylene glycol at a temperature of 370 K for 4 h, followed by the use of 0.5% synthesized solution for encapsulating the granular potassium humate produced from humic acid to give a strength of up to 17.3 kg and prolonged action to the granules. The effect of EPAN concentration on the encapsulation process of granular potassium humates was investigated and studied. The mechanism for the formation of a protective layer of granular potassium humates in the form of a transparent film has been established. The results of the experimental work were processed using the integrated program Statistica-10, which showed a 3D simulation of the process. Microscopic, IR spectral, X-ray phase and thermogravimetric analyses of the encapsulated potassium humate were carried out using modern instrumental devices (MicroXRF Analysis Report, monochromator D878-PC75-17.0, TGA/DSC 1HT/319). The encapsulated durable potassium humate granules provide longer-term nutrition, i.e., a slow, gradual release of plant nutrients in the soil. The use of the produced high-strength encapsulated potassium humate granules allows for restoring soil fertility and increasing the yield of agricultural plants. The encapsulated granules can withstand numerous transshipments and long-term transportation while maintaining the commercial and consumer properties of the product.