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<p>Kraft cellulose from mesquite wood (unbleached, bleached, bleached–refined, and bleached–refined–oxidized) was used at concentrations of 0.1 and 1.0 wt% to synthesize poly (acrylamide-<i>co</i>-potassium acrylate) hydrogels. The fibers were characterized by means of its Kappa number; alpha, beta and gamma cellulose; degree of polymerization; viscometry; optical microscopy and infrared spectroscopy. The alpha cellulose content was 88.3% and 92.9% for the unbleached and bleached pulp, respectively. The degree of polymerization of the unbleached pulp was 679, and after the bleaching, refining, and TEMPO (2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation processes, it was 116. The synthesized hydrogels were characterized via scanning electron microscopy, infrared spectroscopy, swelling kinetics and mechanical and thermal properties. Dried hydrogels (xerogels) were prepared in an oven at 30&#xa0;°C for 3&#xa0;days. The gel fraction (GF) of the synthesized hydrogels was greater than 90.1, and the swelling degree of the hydrogel without fiber was 68.8 ± 3.75. When cellulosic fiber was added, it decreased. The swelling kinetics followed the second-order model proposed by Schott. Young’s modulus increased with the presence of cellulosic fibers. The cellulose treatment significantly influenced the thermal decomposition of the hydrogels. Bleaching, refining, and oxidation improved the thermal stability of the hydrogel, causing decomposition to occur at higher temperatures and more gradually. The hydrogels were used for the removal of Cu<sup>2+</sup> ions from aqueous media, achieving absorption capacities ranging from 90.48 to 98.11&#xa0;mg Cu<sup>2+</sup>/g of xerogel.</p>

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Effect of bleaching, refining and TEMPO oxidation of Prosopis laevigata (mesquite) cellulose pulps on the properties of poly(acrylamide-co-potassium acrylate)/cellulose hydrogels and their use in removing Cu2+

  • 期刊论文

  • 发表日期：

    2025年4月18日

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  • Esteban Vera-Mar,
  • Rosa María Jiménez-Amezcua,
  • Maite Renteria-Urquiza,
  • Jorge Alberto Cortes-Ortega,
  • Eulogio Orozco-Guareño,
  • Ilse Paulina Verduzco-Navarro,
  • Eduardo Gil-Trujillo,
  • José Anzaldo-Hernández,
  • José Antonio Silva-Guzmán,
  • María Guadalupe Lomelí-Ramírez,
  • José Guillermo Torres-Rendón,
  • Salvador García-Enriquez

摘要

Kraft cellulose from mesquite wood (unbleached, bleached, bleached–refined, and bleached–refined–oxidized) was used at concentrations of 0.1 and 1.0 wt% to synthesize poly (acrylamide-co-potassium acrylate) hydrogels. The fibers were characterized by means of its Kappa number; alpha, beta and gamma cellulose; degree of polymerization; viscometry; optical microscopy and infrared spectroscopy. The alpha cellulose content was 88.3% and 92.9% for the unbleached and bleached pulp, respectively. The degree of polymerization of the unbleached pulp was 679, and after the bleaching, refining, and TEMPO (2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation processes, it was 116. The synthesized hydrogels were characterized via scanning electron microscopy, infrared spectroscopy, swelling kinetics and mechanical and thermal properties. Dried hydrogels (xerogels) were prepared in an oven at 30 °C for 3 days. The gel fraction (GF) of the synthesized hydrogels was greater than 90.1, and the swelling degree of the hydrogel without fiber was 68.8 ± 3.75. When cellulosic fiber was added, it decreased. The swelling kinetics followed the second-order model proposed by Schott. Young’s modulus increased with the presence of cellulosic fibers. The cellulose treatment significantly influenced the thermal decomposition of the hydrogels. Bleaching, refining, and oxidation improved the thermal stability of the hydrogel, causing decomposition to occur at higher temperatures and more gradually. The hydrogels were used for the removal of Cu2+ ions from aqueous media, achieving absorption capacities ranging from 90.48 to 98.11 mg Cu2+/g of xerogel.