Chemistry Department, Faculty of Science, Damnhour University, Damnhour 22511,Egypt.
Chemistry Department, Faculty of Science, Alexandria University, Alexandria 21231, Egypt.
Int J Biol Macromol. 2020 Nov 15;163:2180-2188. doi: 10.1016/j.ijbiomac.2020.09.090. Epub 2020 Sep 15.
Two novel chitosan Schiff bases namely chitosan pyrazolo[3,4-b]quinoxaline Schiff base (Ch-PQ) and chitosan phenyl-1H-pyrazolo[3,4-b]quinoxaline Schiff base (Ch-PQ) were synthesized as a modification of chitosan in order to increase its ability in heavy metal removal from wastewater. Their structures were characterized by FT-IR spectroscopy, TGA analysis and X-ray diffraction. They were tested for the removal of hexavalent chromium from synthetic samples. In addition pH conditions, polymer dosage, Cr (VI) initial concentration and contact time were studied as a key factor for the adsorption process. Kinetic studies of the removal process were also clarified. Furthermore, experimental equilibrium data were fitted to Langmuir and Freundlich adsorption isotherms. Both chitosan Schiff bases showed high removal efficiency, the result indicated that Cr (VI) removal using Ch-PQ and Ch-PQ was 96.4% and 98.8% respectively.
两种新型壳聚糖席夫碱，即壳聚糖吡唑并[3,4-b]喹喔啉席夫碱（Ch-PQ）和壳聚糖苯基-1H-吡唑并[3,4-b]喹喔啉席夫碱（Ch-PQ），被合成作为壳聚糖的改性，以提高其从废水中去除重金属的能力。它们的结构通过傅里叶变换红外光谱（FT-IR）、热重分析（TGA）和 X 射线衍射（XRD）进行了表征。它们被测试用于去除合成样品中的六价铬。此外，还研究了 pH 值条件、聚合物用量、Cr(VI)初始浓度和接触时间等关键因素对吸附过程的影响。还澄清了去除过程的动力学研究。此外，实验平衡数据拟合了 Langmuir 和 Freundlich 吸附等温线。两种壳聚糖席夫碱都表现出很高的去除效率，结果表明，使用 Ch-PQ 和 Ch-PQ 去除 Cr(VI)的效率分别为 96.4%和 98.8%。
