Preparation of acrylamide and carboxymethyl cellulose graft copolymers and the effect of molecular weight on the flocculation properties in simulated dyeing wastewater under different pH conditions.
Int J Biol Macromol
; 155: 1142-1156, 2020 Jul 15.
Article
en En
| MEDLINE
| ID: mdl-31726159
ABSTRACT
In this study, graft copolymers with different graft ratios (GRs) and molecular weights (MWs) were prepared by water bath polymerization using acrylamide (AM) and carboxymethyl cellulose (CMC) as substrates; additionally, the best preparation parameters were provided. The MW of the copolymer was inversely correlated with the GR (Râ¯=â¯-0.82). The obtained graft copolymer was characterized by FTIR, 1H NMR, XPS and DSC. The results showed that CMC and AM were successfully copolymerized and the thermal stability of the product is improved. The graft copolymers with different MWs were used to flocculate a simulated dyeing wastewater at pH values of 3, 5, 7, 9 and 11. The results showed that as the molecular weight of the graft copolymers increased, the average flocculation settling ratio decreased drastically from 61.2% to 19.4% at pHâ¯3, and the higher the MW, the better the flocculation settling performance. But the average settling ratio increased sharply at pHâ¯11, and the increase grew from 21.0% to 50.3%. The larger the MW, the more obvious the decrease in flocculation sedimentation performance. The supernatant turbidity was reduced from 13324 NTU to less than 150 NTU, and the turbidity removal ratio exceeded 99%. The flocculation mechanism was discussed.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
2_ODS3
Problema de salud:
2_quimicos_contaminacion
Asunto principal:
Polímeros
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Carboximetilcelulosa de Sodio
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Purificación del Agua
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Acrilamida
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Colorantes
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Aguas Residuales
Idioma:
En
Revista:
Int J Biol Macromol
Año:
2020
Tipo del documento:
Article