Title
Preparation of a hydrogel composite from recycled cellulose and its use urea release
Authors
KAMEL MOKHNACHE, KHAYERDDINE KHROUFI and SALIM MADANI

Received August 23, 2024
Published Volume 59 Issue 1-2 January-February
Keywords baby diapers, cellulose extraction, material composite, urea release, barley

Abstract
The aim of this study has been to develop a hydrogel composite based on recycled cellulose extracted from used baby diapers. The prepared composite was intended for agricultural applications, specifically for the controlled release of fertilizer (urea). To this end, used baby diapers were processed to extract cellulose, which was then sterilized and treated with acetic acid. The recycled cellulose was mixed with starch and citric acid, followed by precipitation with zinc ions to form the hydrogel composite. The resulting hydrogel composite had a heterogeneous structure due to the mixing of various components and exhibited a degree of thermal stability. The material demonstrated a very high water absorption capacity, achieving a swelling ratio of 260% within 4 hours, and released urea rapidly into the aqueous medium (40% after 2 hours). Urea release was governed by a simple diffusion mechanism. Growth tests on barley plants indicated that the urea-containing hydrogel promoted greater growth in both length and width, compared to the plants grown without the hydrogel, with more pronounced differences observed in length. The controlled release of urea from the hydrogel is crucial for optimizing barley plant growth. This study opens up promising avenues for waste recovery and the development of sustainable materials for agriculture.