Nitro-oxidation process for fabrication of efficient bioadsorbent from lignocellulosic biomass by combined liquid-gas phase treatment
Nitro-oxidation process for fabrication of efficient bioadsorbent from lignocellulosic biomass by combined liquid-gas phase treatment
复制标题
DOI：
10.1016/j.carpta.2022.100219
复制
发表时间：
2022-05-26
影响因子：
5.5
通讯作者：
Hsiao, Benjamin S.
中科院分区：
文献类型：
--
作者：
Chen, Hui;Chi, Kai;Hsiao, Benjamin S.
采用液相HNO3脱木质素、气相no2诱导纤维素氧化的顺序处理方法对黄麻原纤维进行处理。系统地表征了每一步处理材料的结构、化学成分、形貌和表面性能。首先，在温和的HNO3条件下（30%,25℃，6 h），黄麻纤维可以发生脱木质素作用，能够在不改变天然纤维素I结构的情况下去除大部分木质素。随后，气相NO2处理可以氧化部分脱木质素的黄麻纤维，并在材料表面产生高浓度的羧基（1.31-1.45 mmol/g），与tempo介导的氧化相当。所得材料能有效去除带正电荷的污染物，如水中的铊(I)离子（去除率约为80%）。混合液气相氮氧化工艺（NOP）为木质纤维素生物质制备水修复吸附剂提供了更好的纤维素氧化控制，并且由于气相NO2处理后氧化纤维素不需要洗涤，进一步降低了能源和水的消耗。
A sequential treatment involving HNO3 delignification in liquid phase and NO2-induced cellulose oxidation in gas phase was applied to raw jute fibers. The structure, chemical compositions, morphology and surface properties of the treated materials in each step were systematically characterized. First, delignification of jute fibers could occur at a mild HNO3 condition (30%, 25 degrees C, 6 h), capable of removing a significant portion of lignin without changing the native cellulose I structure. Subsequently, gas-phase NO2 treatment can oxidize partially delignified jute fibers and produce high concentrations of carboxyl groups (1.31-1.45 mmol/g) on the material surface, comparable to TEMPO-mediated oxidation. The resultant material is effective in removing positively charged contaminants, such as Thallium(I) ions from water (the removal efficiency >80%). The mixed liquid-gas phase nitro-oxidation process (NOP) provides better control of cellulose oxidation for fabrication of water remediation adsorbents from lignocellulose biomass and further reduces the energy and water consumption since there is no requirement for washing the oxidized cellulose after gas-phase NO2 treatment.