The leaching and stabilizing characteristics of synthetic copperdiethyl dithiocarbamate (Cu-DDTC) under 1 N acetic acid solution werecharacterized using semi-dynamic leaching test (SDLT),ultraviolet-visible spectrophotometer (UV-visible), X-raydiffractometer (XRD), Fourier transform infrared spectrophotometer(FTIR), and scanning electron microscopy (SEM) techniques. Theanalyses of leached species of leaching solution by SDLT andUV-visible indicated that the degree of degradation of variouselements from the Cu-DDTC complex could be classified as: N (25/100)>S (20/100) > Cu(0.7/100) and no dithiocarbamate species in the liquidphase were detected. The copper species of insoluble Cu-DDTCcomplexes were much more stable than those of copper solidificationin cementitious matrix. The investigation of crystallinity showedthat there were two unidentifiable peaks present in the XRD patternof the leached Cu-DDTC complex that might be attributed to newchemical interactions. The spectra obtained by FTIR analysesobviously showed that the major functional groups, such as C-N, S-C,C=S, Cu-S and C-H groups, were both present in the unleached andleached Cu-DDTC complex. Microstructural analyses by SEM revealedthat the unleached and leached Cu-DDTC complexes had the samemorphologies, but the grain size of the leached Cu-DDTC complex ismuch larger and compact than that of the unleached complex. Thus, itwas suggested that the leaching and stabilizing characteristics ofthe insoluble Cu-DDTC complexes consisted of the dissolution anddecomposition of Cu-DDTC and the chelatin
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