synopsisThe chelating polymer-bearing triazolylazophenol moiety as the functional group was synthesized, its metal adsorption properties for 6 divalent heavy metal ions; Co2+, Ni2+, Cuz+, Zn2+, Cd2+, and Pb2+ were investigated. The capacity of the polymer for Cu2+ achieved 8.7 m&/g in pH 5.3 solution. The polymer showed remarkable color changes from orange to red violet or blue violet with its chelations to the heavy metal ions. The metal adsorption rates of the polymer were rapid in performing complete capacity saturation of heavy metal ions in about 30 min. The capacities varied little the presence of alkali or alkaline earth metal ions in solutions. The perfect elimination of metals from the polymer-M2+ chelates were performed with mineral acid solutions. The metal ions; Cu2+ and Ni2+ in plating-process solutions were effectively removed by the chelating polymer, and the polymer can be practically used for the removal of these ions from waste water.
The substituent effect on the ozone decoloration reactions of 1-(m-substituted phenylazo)-2-naphthol-6-sulfonic acids (PANSA) in aqueous solutions was investigated. Both the acidities of PANSA and the variation of the ozone decoloration rates of them increased compared to those of the corresponding 1-(m-substituted phenylazo)-2-naphthol-3,6-disulfonic acids (PANDSA). The relationships between the decoloration rates and the indexes(pKOH and σm values) of the basicities of the dyes, however, indicated nearly the same characteristics between the data of these two series of dyes, and the ozone decoloration reactions of PANSA appeared to proceed by nearly the same mechanism as those of PANDSA. The changes of the keto–enol ratios of the dyes with their ozone decolorations suggested that the decoloration rates might rise as the reduction rates of their keto–enol ratios increased. It seems likely that the chief organic product that was finally produced in these reactions is oxalic acid.
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