Physical and Chemical Properties of Silver-Containing Nanosorbent Obtained from Rice Straw Biochar

Abstract

Improving the quality of natural water purification is one of the priority areas in the research conducted by scientific communities in the field of ecology. At the same time, the task is to achieve the optimal efficiency of the technological process at a low cost. The solution, in this case, is the use of materials necessary for cleaning, in particular, sorbents from natural raw materials, including agricultural waste. At present, a sufficient number of research results have been published confirming the effectiveness of the sorbent from biochar from various types of agricultural waste, as well as from rice straw biochar (RSB). This article proposes an innovative method for modifying biochar from rice straw, which allows the use of the material as a sorbent with a disinfecting effect. The method consists of processing biochar in a process activation plant (PAP) using a solution of silver nitrate, which is released in the form of a carbon nanomaterial with attached metallic silver ions on the surface of biochar particles. The biochar impregnated with a solution of silver nitrate was contacted with ferromagnetic particles under electromagnetic influence, followed by thermal treatment of the sample. The resulting silver-containing sorbent was subjected to a physicochemical analysis of its properties; photographs of electron microscopy were also obtained, and a bacteriological analysis of the effectiveness of the sorbent on natural water was carried out. The analysis was carried out on three indicators—total microbial count (TMC), total number of coliform bacteria (TCB), and thermotolerant coliform bacteria (TCB). According to the research results, the sorbent showed its disinfecting properties and confirmed its high efficiency (90.48–100%).