为活性炭应用于酚醛类化工废水深度处理,研究了活性炭对此类废水中有机物的动态吸附性能以及氮的去除。通过动态吸附试验,选出吸附效果最佳的活性炭,研究其对废水中有机物的等温吸附和动力学,并利用比表面积(BET)测试法和傅里叶红外光谱...为活性炭应用于酚醛类化工废水深度处理,研究了活性炭对此类废水中有机物的动态吸附性能以及氮的去除。通过动态吸附试验,选出吸附效果最佳的活性炭,研究其对废水中有机物的等温吸附和动力学,并利用比表面积(BET)测试法和傅里叶红外光谱(FTIR)表征技术分析活性炭表面特征,同时探讨不同因素对吸附的影响,再以床厚服务时间(Bed-Depth-Service Time, BDST)模型对动态试验数据进行线性拟合分析。结果表明:椰壳炭吸附效果最好,朗格缪尔(Langmuir)吸附等温线模型和拟二级动力学模型可以较好地描述其动态吸附行为;吸附过程中粒子内扩散并不是唯一的限速步骤,有机物的吸附主要发生在边界层扩散阶段;根据椰壳炭孔状结构的变化说明吸附主要发生在微孔区;—OH、—COOH、C=C等官能团能与有机物相互反应,主要涉及氢键、π-π相互作用、静电引力;含氮化合物会与有机物产生竞争吸附,影响其吸附量;BDST模型不仅可以有效描述吸附床高度与穿透时间之间的关系,而且能够准确地预测新的操作条件下的有机物穿透时间,误差均小于5%。展开更多
Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of ir...Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values.展开更多
采用β-环糊精对木屑改性用于吸附苯胺,通过固定床实验考察了吸附床高度（10～30 mm）、进水流速（2.7～8.1 m L·min-1）和苯胺初始浓度（50～200 mg·L-1）对穿透曲线的影响,同时使用BDST模型对吸附穿透曲线进行拟合。结果表...采用β-环糊精对木屑改性用于吸附苯胺,通过固定床实验考察了吸附床高度（10～30 mm）、进水流速（2.7～8.1 m L·min-1）和苯胺初始浓度（50～200 mg·L-1）对穿透曲线的影响,同时使用BDST模型对吸附穿透曲线进行拟合。结果表明,改性木屑可以有效吸附苯胺,随着高度的增加,穿透时间延长,固定床对苯胺的去除率增大;随着苯胺进水流速和初始浓度的增加,穿透时间缩短,固定床对苯胺的去除率降低;BDST模型对穿透曲线的拟合效果较好（Ct/C0=0.7,R2=0.999 0）,随着运行时间的增加,固定床的吸附速率常数（Ka）变小,对苯胺的吸附量（N0）增大;当改变流速时,运用该模型能较准确的预测吸附固定床的操作时间。展开更多
文摘为活性炭应用于酚醛类化工废水深度处理,研究了活性炭对此类废水中有机物的动态吸附性能以及氮的去除。通过动态吸附试验,选出吸附效果最佳的活性炭,研究其对废水中有机物的等温吸附和动力学,并利用比表面积(BET)测试法和傅里叶红外光谱(FTIR)表征技术分析活性炭表面特征,同时探讨不同因素对吸附的影响,再以床厚服务时间(Bed-Depth-Service Time, BDST)模型对动态试验数据进行线性拟合分析。结果表明:椰壳炭吸附效果最好,朗格缪尔(Langmuir)吸附等温线模型和拟二级动力学模型可以较好地描述其动态吸附行为;吸附过程中粒子内扩散并不是唯一的限速步骤,有机物的吸附主要发生在边界层扩散阶段;根据椰壳炭孔状结构的变化说明吸附主要发生在微孔区;—OH、—COOH、C=C等官能团能与有机物相互反应,主要涉及氢键、π-π相互作用、静电引力;含氮化合物会与有机物产生竞争吸附,影响其吸附量;BDST模型不仅可以有效描述吸附床高度与穿透时间之间的关系,而且能够准确地预测新的操作条件下的有机物穿透时间,误差均小于5%。
文摘Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values.
