Removal of chromium (Ⅵ) from aqueous solutions using quaternized chitosan microspheres

来源 :Chinese Journal of Chemical Engineering | 被引量 : 0次 | 上传用户:2km
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
In this study, quaternized chitosan microspheres(QCMS) were prepared and its Cr(VI) removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, p H effect,and thermodynamic parameters. Equilibrium was attained within 50 min and maximum removal of 97.34%was achieved under the optimum conditions at p H 5. Adsorption data for Cr(VI) uptake by the QCMS were analyzed according to Langmuir, Freundlich, and Temkin adsorption models. The maximum uptake of Cr(VI)was 39.1 mg·g~(-1). Thermodynamic parameters for the adsorption system were determinated at 293 K, 303 K,313 K and 323 K.(ΔH° = 16.08 k J·mol~(-1);ΔG° =- 5.84 to- 8.08 k J·mol~(-1)and ΔS° = 74.81 J·K~(-1)·mol~(-1)).So the positive values of both ΔH° and ΔS° suggest an endothermic reaction and increase in randomness at the solid–liquid interface during the adsorption. ΔG° values obtained were negative indicating a spontaneous adsorption process. The kinetic process was described by a pseudo-second-order rate equation very well. The results of the present study indicated that the QCMS could be considered as a potential adsorbent for Cr(VI) in aqueous solutions. In this study, quaternized chitosan microspheres (QCMS) were prepared and its Cr (VI) removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, p H effect, and thermodynamic parameters. Equilibrium was attained within 50 min and maximum The maximum uptake of Cr (VI) was 39.1 mg · G ~ (-1). Thermodynamic parameters for the adsorption system were determined at 293 K, 303 K, 313 K and 323 K. (ΔH ° = 16.08 kJ · mol -1; ΔG ° = - 5.84 to - 8.08 kJ · mol -1 and ΔS ° = 74.81 J · K -1 · mol -1). So the positive values ​​of both ΔH ° and ΔS ° suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. ΔG ° values ​​obtained were negative indicating a spontaneous adsorption process. The kinetic process was described by a pseudo-second-order rate equation very well. The results of the present study indicate that the QCMS could be considered as a potential adsorbent for Cr (VI) in aqueous solutions.
其他文献
2000年12月1日(以下简称)正式施行,2001年2月26日,农业部发布了等5个配套规章,对进行细化,大大增加了的可操作性.及其配套规章对种子选育、生产、经营、使用行为进行严格规范
This work was focused on the measurement of the solubility of hydrogen(H_2) in anthraquinone working solution at temperatures of 30.0–80.0 °C and pressures of
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
期刊
两间总共不到30平方米的屋子里,安设了几张桌子,桌上摆放几件工器具,墙上几张组织机构图,门外再挂几块牌子,既可以是职工创新工作室,也可以是劳模技师工作室,只要换块牌子,还
期刊
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
期刊
农业部第49号令第四条规定:农作物种子标签应当标注作物种类、种子类别、品种名称、产地、种子经营许可证编号、质量指标、检疫证明编号、生产年月、生产商名称、生产商地址
A preparation process of 2-methylnaphthalene(2-MN) was proposed by isomerization, side-stream distillation and extractive distillation. The isomerization of alk
“我们都是追梦人”,历史会记得,2019年的中国,全民追梦的起点.rn“飞雪迎春到”.雨雪过后,兆丰年的愿景稍远了点,但仅仅是洗车涨价,就让忙活的洗车店“小老板”们高兴得合不
期刊
1我省种业的现状及其发展的制约因素分析rn改革开放以来,我省种业在一些方面得到了一定的发展.截至2000年,全省有国有种子公司86家,良(原)种场105个,种子科研院所42个,年繁制
如水的眷恋终是阻挡不了岁月的脚步,当日历撕下最后一页,新的一年又走来了.rn从三月初芽的一点新绿,秋天的落叶凋零,再到寒风中的凭栏看落雪,匆匆一年,便辗转而过,如清风吹过
期刊