In my diploma thesis, the sorption of metals on three different biochar samples using SEM/EDS analysis was studied. The first two samples are of plant origin, the first (LS) obtained by pyrolysis of wood chips, and the second (CG) a commercially available biochar of Carbon Gold. The third biochar sample (ABC) is of animal origin, obtained by pyrolysis of animal bone meal. Biochar samples were determined by the content of hygroscopic moisture and ash content and the content of P, Ca, Mg, K, Na and Fe. The samples were embedded in a resin and by means of SEM analysis, observed the surface of both the prepared basic samples and the samples after exposure to solutions of Pb2+, Cd2+ and CrO42- ions. With the EDS analysis, I determined the elemental composition of individual components of biochar and evaluated the potential binding sites of individual metals. The results showed that the highest proportion of P, Ca, and Na contained the sample ABC, which is not too surprising given its origin. The lowest content of P and Ca were found in the sample CG and the lowest content of Na in the biochar LS. The highest proportion of Mg, Fe and K contains a sample of LS that is of plant origin and the least sample of animal origin ABC. SEM/EDS analysis showed that all three biochar samples have binding affinities for all three metal ion species, but sorption occurs only on the mineral particles of the biochar samples, while no sorption on organic part of biochar samples.
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