共查询到20条相似文献,搜索用时 31 毫秒
1.
姚春才 《中国化学工程学报》2004,12(2):297-301
Three adsorption rate models are derived for multicomponent adsorption systems under either pore diffusion or surface diffusion control. The linear driving force (LDF) model is obtained by assuming a parabolic intraparticle concentration profile. Models I and Ⅱ are obtained from the parabolic concentration layer approximation. Examples are presented to demonstrate the usage and accuracy of these models. It is shown that Model I is suitable for batch adsorption calculations and Model Ⅱ provides a good approximation in fixed-bed adsorption processes while the LDF model should not be used in batch adsorption and may be considered acceptable in fixed-bed adsorption where the parameter Ti is relatively large. 相似文献
2.
3.
4.
固体吸附式制冷因具有环保和节能两大优势,成为国内外竞相开发的热点,尤其是将其用于新型空调系统和太阳能应用产品方面的开发研究备受关注.但从实用化研究成果来看,还远不满足工业化条件,其主要原因之一是受吸附制冷工质对(吸附剂-制冷剂)的性能制约.目前,国内外关于吸附制冷工质对的研究报道比较多,所采用的吸附(工)质仍然以水、甲醇、乙醇和氨为主,对于吸附剂的研究进展比较快,已从当初单一组分吸附剂的选用发展到目前多组分、复合吸附剂的研制.研制性能优良的吸附剂被认为是推动固体吸附式制冷工业化的关键之一. 相似文献
5.
生物吸附剂BAP对Cu^2+的吸附研究 总被引:11,自引:0,他引:11
本文研究了溶液PH和混合程度对生物吸附剂BAP的Cu^2+记吸附性能的影响,及相应的静态吸附动力学吸附方程,以及吸附剂的再生情况。与文献报道的其他中附剂相比,该吸附剂有较好的吸附和操作稳定性 相似文献
6.
通过静态吸附和动态吸附法研究了水杨酸修饰的超高交联吸附树脂(SYS树脂)对苯酚的吸附行为,实验静态数据分别用Langmuir、Freundlich和Dubinin-Radushkevich等温方程拟合,动态数据用准一级动力学和准二级动力学模式拟合。结果表明,SYS树脂在一定的温度下对苯酚既存在物理吸附又存在化学吸附,吸附过程为一级动力学吸附过程。 相似文献
7.
Four models for the rate of adsorption in an adsorbent(slab-like,cylindrical or spherical)arepresented.The parabolic profile(PP)model is obtained by assuming a parabolic intraparticle concentrationprofile.The shell-core(SC)model is based on a shell-core type profile.The modified shell-core(MSC)medel isan extension of the SC model.And the general driving force(GDF)model is a weighted average of the PP andMSC models.Sample calculations show that the GDF model provides the best approximation. 相似文献
8.
10.
环保型吸附制冷工质对及其制冷性能 总被引:2,自引:0,他引:2
选取13X分子筛、凹凸棒土和氯化锶等为主要吸附材料,制备了一系列有着优良吸附性能的复合吸附剂(M4-0132、M1-9906、M1-0001和M2-0003)。测定了水、乙醇在自制复合吸附剂上的吸附等温线。根据吸附等温线拟合参数对水、乙醇与自制复合吸附剂组成的吸附工质对的特征吸附功计算表明:复合吸附剂-水吸附工质对的特征吸附功约为13X分子筛-水的12%-29%;复合吸附剂-乙醇吸附工质对的特征吸附功约为活性炭-乙醇的10%-20%。采用吸附制冷体系(液体-气体-吸附剂)的稳态平衡方程,对水和乙醇与复合吸附剂组成的吸附工质对适合的制冷场合分析表明:M4-0132-水和M1-0001-水工质对可用于大循环量的制冷体系,例如空调系统的场合:M1-9906-乙醇和M2-0003-乙醇工质对可用于低温制冷体系,例如制冰和冷冻系统的场合。M1-9906-水工质对的吸附制冷量是13X-水的2.0~2.5倍;在60~120℃再生条件下,M4-0132-水工质对的吸附制冷量为441~924kJ.kg^-1。40~100℃再生条件下,M1-0001-乙醇工质对的吸附制冷量315~909kJ.kg^-1,是活性炭-乙醇的2.2~5.9倍。 相似文献
11.
12.
13.
Ali Kara 《应用聚合物科学杂志》2009,114(2):948-955
Poly(ethylene glycol dimethacrylate‐1‐vinyl‐1,2,4‐triazole) [poly(EGDMA‐VTAZ)] beads (average diameter = 150–200 μm) were prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with 1‐vinyl‐1,2,4‐triazole (VTAZ). Poly(EGDMA‐VTAZ) beads were characterized by swelling studies and scanning electron microscope (SEM). The adsorption of Cr(VI) from solutions was carried at different contact times, Cr(VI) concentrations, pH, and temperatures. High adsorption rates were achieved in about 240 min. The amount of Cr(VI) adsorbed increased with increasing concentration and decreasing pH and temperature. The intraparticle diffusion rate constants at various temperatures were calculated. Adsorption isotherms of Cr(VI) onto poly(EGDMA‐VTAZ) have been determined and correlated with common isotherm equations such as Langmuir and Freundlich isotherm models. The Langmuir isotherm model appeared to fit the isotherm data better than the Freundlich isotherm model. The pseudo first‐order kinetic model was used to describe the kinetic data. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. The dimensionless separation factor (RL) showed that the adsorption of metal ions onto poly(EGDMA‐VTAZ) was favorable. It was seen that values of distribution coefficient (KD) decreasing with Cr(VI) concentration in solution at equilibrium (Ce) indicated that the occupation of activate surface sites of adsorbent increased with Cr(VI). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
14.
15.
16.
17.
18.
通过溶液聚合法来制取功能高分子材料,并研究了引发剂、交联剂、单体用量等对材料吸附性能的影响,研究结果表明:交联剂用量在0.3%时,材料的吸附水和铅离子或铜离子的性能相对较好,对溶液中铜离子的吸附率达到95.2%,吸附量为143 mg/g,对铅离子的吸附率达到84.8%,吸附量为85 mg/g;引发剂用量在0.5%时,材料的吸附水和铅离子或铜离子的性能相对较好,对溶液中铜离子的吸附率达到94.8%,吸附量为142 mg/g,对铅离子的吸附率达到87.9%,吸附量为88 mg/g;当SAS用量为20%时,材料的材料的吸附水和铅离子或铜离子的性能相对较好,对溶液中铜离子的吸附率达到94.7%,吸附量为142 mg/g,对铅离子的吸附率达到87.8%,吸附量为88 mg/g. 相似文献
19.
为评价活性焦脱硫特性,选取现有活性焦,在微分反应装置上考察烟气组分对吸附硫容的影响及SO2浓度对吸附量、吸附速度的影响。试验结果表明:烟气组分中SO2、氧、水蒸汽体积分数增加有利于提高活性焦吸附硫容,而随床层温度的升高,活性焦吸附硫容降低。活性焦吸附符合Bangham吸附速率模型,采用较高SO2体积分数的模拟试验气体,吸附速度衰减很快,将商用大颗粒活性焦破碎至2~3 mm,在SO2为10000×10-6的模拟试验气体工况的条件下吸附,吸附4 h后,其吸附硫容增量小于5%,可将其4 h吸附SO2量作为活性焦的吸附硫容。 相似文献
20.
本文通过在120℃条件下在DMF中回流用ZrCl4和2-氨基对苯二甲酸合成了金属-有机骨架化合物UiO-66-NH2,再在氮气保护下在乙醇中回流用3,4-二羟基苯甲醛对UiO-66-NH2进行了功能化修饰,获得了UiO-66-OHBA。通过红外光谱、元素分析以及X射线粉末衍射实验证明了3,4-二羟基苯甲醛成功修饰了UiO-66-NH2,且修饰后获得的UiO-66-OHBA骨架结构并未发生改变。以UiO-66-NH2和UiO-66-OHBA为吸附剂吸附U(Ⅵ)并研究了pH、固液比、反应温度、离子强度、平衡时间等对吸附行为的影响,并对结果进行了分析。实验结果表明UiO-66-NH2和UiO-66-OHBA均对U(Ⅵ)表现出比较良好的吸附能力,并且经修饰后的吸附剂吸附性能得到了提升。pH值对吸附性能有较大影响,两者均在pH为4.5处吸附速率最大。温度对UiO-66-OHBA吸附性能的影响要小于UiO-66-NH2,它们的吸附模型与Freundlich等温吸附模型吻合良好。 相似文献