荆树皮栲胶/纤维素-聚乙烯亚胺气凝胶吸附阿散酸的研究

Study on Adsorption of p-Arsanilic Acid by Wattle Extract/Cellulose-Polyethylenimine Aerogel

中文关键词:  纤维素气凝胶  荆树皮栲胶  聚乙烯亚胺  吸附  阿散酸

Key Words:cellulose aerogel  wattle extract  polyethylenimine  adsorption  p-arsanilic acid

中文摘要:

      以纤维素为原料，采用NaOH/尿素/水混合溶液溶解纤维素，通过溶胶-凝胶法将荆树皮栲胶（BWT）和聚乙烯亚胺（PEI）接枝到纤维素上以制备荆树皮栲胶/纤维素-聚乙烯亚胺气凝胶（（Cell/BWT）@PEI），通过扫描电子显微镜（SEM）、比表面积（BET）分析、热分析（TG-DTG）等手段对其进行结构表征和性能分析，并且研究了其对阿散酸（p-ASA）的吸附性能。结果表明，（Cell/BWT）@ PEI比表面积为190.5 m²/g，孔径为15.2 nm，具有较好的热稳定性；当p-ASA初始质量浓度为100 mg/L、溶液pH值为5.0、吸附时间为360 min、吸附温度为25℃、（Cell/BWT）@PEI投加量为0.4 g/L时，（Cell/BWT）@PEI对p-ASA的平衡吸附容量（Q_e）为163.3 mg/g，去除率为65.3%；（Cell/BWT）@PEI对p-ASA的吸附为化学吸附，Freundlich等温吸附方程更适于描述（Cell/BWT）@PEI对p-ASA的吸附，且吸附过程自发进行；吸附再生实验结果表明，循环再生5次后，（Cell/BWT）@PEI对p-ASA的Q_e为107.2 mg/g、去除率为42.9%。

Abstract:

      A novel functionalized cellulose aerogel was successfully prepared by sol-gel method to graft wattle extract （BWT） and polyethylenimine （PEI） on cellulose using NaOH/urea/water as solvent. Scanning electron microscopy （SEM）， specific surface area （BET） analysis， thermal analysis （TG-DTG）， etc. were used to characterize the structure and properties of the as-prepared wattle extract/cellulose-PEI aerogel （（Cell/BWT）@PEI） and its adsorption performance on p-arsanilic acid （p-ASA） was studied as well. The results showed that the specific surface area of （Cell/BWT）@PEI was 190.6 m²/g， the pore diameter 15.2 nm， and it had good thermal stability. The equilibrium adsorption capacity （Q_e） of （Cell/BWT）@PEI for p-ASA was 163.3 mg/g and the removal rate was 65.3% when the initial mass concentration of p-ASA was 100 mg/L， pH value of solution 5.0， adsorption time 360 min， adsorption temperature 25℃， and dosage of （Cell/BWT）@PEI 0.4 g/L. Moreover， the adsorption of p-ASA by （Cell/BWT）@PEI was a chemical and spontaneous process， conforming more to the Freundlich isothermal adsorption equation. The results of adsorption regeneration experiments showed that after 5 cycles of regeneration， the Q_e of （Cell/BWT）@PEI for p-ASA was 107.2 mg/g and the removal rate was 42.9%.