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超声波对苯酚在NKAⅡ树脂上吸附平衡的影响 总被引:5,自引:0,他引:5
本文以苯酚水溶液/NKAⅡ树脂吸附体系为实验对象,研究超声波对液固吸附平衡的影响。分别测定了在超声场和无超声场条件下,苯酚在NKAⅡ树脂上的吸附等温线,报道了在超声场条件下苯酚在高聚物吸附剂上的吸附等温线。研究结果表明:超声场作用下的吸附平衡等温线要低于在常规条件下的吸附等温线,超声场强度越大,苯酚在吸附剂上的吸附容量就越小。向吸附体系施加超声场,会导致吸附体系的温度升高。超声场对吸附平衡的影响是由超声场的热效应和非热效应所引起的,而后者的影响要大于前者。向液固吸附体系添加乙醇或乙酸乙酯作为第三组分,能进一步使体系的相平衡关系朝着吸附量减少的方向移动,这种变化在超声波场条件下更为明显。 相似文献
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实验研究了酪氨酸和苯丙氨酸在不同pH值溶液中在活性炭上的吸附平衡。单组分的吸附平衡数据采用Freundlich等温线拟合;提出了简单的双组分吸附平衡方程。这些等温线可在吸附过程的开发中得到应用。 相似文献
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The XG equation, which is developed by us previously for describing the adsorption equilibrium of pure vapor on activated carbon, is extended to multi-component system. Verified by experimental data, the extended XG equation was found to be more successful in predicting the adsorption equilibrium of vapor mixture on activated carbon than the extended Langmuir equation, the extended BET equation and the ideal adsorbed solution theory (IAST). 相似文献
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在用三种方法(摩尔体积、分子等张比容及摩尔电子极化度)计算亲和系数β的基础上,用polanyi-Dubinin方程预计了25℃下八种有机蒸汽以及25、40和60℃下另两种有机蒸气在活性炭上的吸附等温线.相应的实验数据用重量法测定.预计的和实验的数据对比表明:(1)对于优化的预计,参照物应与被预计吸附质有相似的极性;(2)选择适宜的参照物后,三种预计方法在精度上无明显差异;(3)对不同温度下的预计,摩尔体积法更为简便、实用. 相似文献
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Adsorption equilibrium isotherms of benzene in the concentration range of 500-4000 mg·@m-3 on two commercial activated carbons were obtained using long-column method under 30℃ and different humidity conditions. Results show that the benzene and water vapors have depression effects upon the adsorption of each other and that the unfavorable effect of water vapor resembles its single-component isotherm on activated carbon. A competitive adsorption model was proposed to explore the depression mechanisms of the non-ideal, non-similar binary adsorption systems. A modified Polanyi-Dubinin equation was set up to correlate the binary adsorption equilibrium and to calculate the isotherms of benzene on activated carbon in presence of water vapor with considerable precision. 相似文献
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1前言在含酚废水的实际处理中,生化法应用最广泛,效果也好,但是一些中、小企业产生的含酚树脂废水往往不具备生化法所要求的条件。这些废水排放量小,水质不稳定,又是间歇排放,所以不适合用生化法处理。另外,生化法基建投资高、管理要求严、管理费用高,使一些中、... 相似文献
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《分离科学与技术》2012,47(2):300-308
The potential use of different activated carbons (ACs) prepared from dates pits and phosphoric acid for the removal of phenol from aqueous solutions was investigated. Date pits were converted into five different types of activated carbons by air and phosphoric acid activation. The specific surface area (BET) of the prepared ACs varied from 794 m2/g, for the phosphoric acid:date pit ratio of 5:1, to 1707 m2/g for a ratio of 2:1. Batch adsorption experiments revealed that the adsorption of phenol varied among all of the prepared ACs, where the 2:1 AC showed the highest uptake. Equilibrium pH studies showed that the phenol removal was pH dependent and the maximum phenol uptake occurred at an equilibrium pH of 3.0. Dynamics studies indicated that the initial uptake of phenol on 2:1 AC at pH 4 was rapid, where 80% of the maximum uptake was achieved during the first 30 minutes; both surface adsorption and intraparticle diffusion were involved in the adsorption process and the data followed the pseudo second-order reaction. The equilibrium adsorption data of phenol on 2:1 AC at solution pH 3 was best described by the Redlich-Peterson, Sips, and Langmuir models. 相似文献
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《分离科学与技术》2012,47(2):340-348
The liquid-phase adsorption of phenol and dye (basic violet 10) onto carbon nanotube (CNT)-activated carbon fabric (ACF) composites, prepared by a catalytic chemical vapor deposition (CCVD) approach, has been investigated. The CCVD technique enables the decoration of CNTs on microscaled ACFs, creating a hierarchy CNT-ACF composite. The as-grown nanotubes were found to have a tortuous shape and to be several micrometers in length. The deposition of CNTs efficiently shifts the micropore size distribution of ACFs to mesoporosity. The adsorption isotherms for phenol and BV10 on ACF and CNT-ACF adsorbents are well characterized by the Dubinin-Radushkevich and Langmuir models. The surface accessibility, the equilibrium rate constant, and the adsorption energy are significantly enhanced due to the deposition of CNTs, as analyzed by these models. Accordingly, the existence of CNTs on ACF adsorbent plays a positive role in facilitating pore accessibility to adsorbate and providing more adsorptive sites for the liquid-phase adsorption. 相似文献
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Substrate inhibitions that manifest within the cometabolism system of 4‐chlorophenol (4‐cp) and phenol were alleviated through the application of granular activated carbon (GAC) in batch biodegradation. It was found that 4‐cp was preferentially adsorbed over phenol by the GAC and that 50% to 70% of the adsorption was achieved within the first two hours of contact. The kinetics of 4‐cp adsorption was also much faster than that of phenol, even when the co‐existing phenol was of a significantly higher initial concentration. As a result, competitive inhibition between the two compounds was minimized. Adsorption also caused a lowering of the phenol concentration in solution with a concomitant reduction in the substrate inhibition effect on cell growth. The addition of GAC benefited the biotransformation process through shortening the total degradation time for 600 mg L?1 phenol and 100 mg L?1 4‐cp from 42 h to 12 h; and it also made it possible for cells to survive and transform 600 mg L?1 phenol and as high as 400 mg L?1 4‐cp in free suspension cultures. Repeated operations in which GAC was reused showed that GAC could be regenerated by the cells, thus rendering the GAC incorporated process amenable to long term operations. 相似文献
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活性炭对丁酮的吸附动力学研究 总被引:1,自引:0,他引:1
研究了2种活性炭(木质活性炭和煤质活性炭)对丁酮的吸附,重点考察了活性炭的吸附时间、吸附温度和丁酮载气流量对丁酮吸附的影响,并用准一级、准二级、Elovich和Bangham 4种动力学模型对活性炭在不同温度条件下对丁酮的吸附行为进行了动力学拟合,确定其动力学吸附模型。实验表明:不同的活性炭对丁酮的吸附过程不同;活性炭对丁酮的吸附是一个吸附和解吸同时存在的过程,当吸附速率和解吸速率相等时,该过程达到吸附平衡;随着吸附温度的升高,活性炭对丁酮的饱和吸附量逐渐降低,说明活性炭对丁酮的吸附过程为放热反应;丁酮载气流量对活性炭吸附丁酮达到饱和的时间以及吸附速率有影响,对AC-1的最终饱和吸附量影响显著,对AC-2的最终饱和吸附量没有显著影响。这2种活性炭吸附丁酮最适宜的吸附温度均为303 K,最佳的载气流量为400 mL/min。在不同温度下对活性炭吸附丁酮的过程进行动力学分析,发现Bangham方程计算得到的相关系数R2大于0.99,因此,活性炭对丁酮的吸附动力学方程符合Bangham动力学方程。 相似文献
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以农业废弃物棉秆为原料,采用氢氧化钾活化法制备活性炭,并用于吸附含苯酚废水中的苯酚。棉秆基活性炭的最佳制备条件为棉秆先炭化,以KOH溶液为活化剂,KOH与棉秆炭的质量比(物料比)1.5:1,活化温度800 ℃、活化时间70 min,此条件下制备的棉秆活性炭亚甲基蓝的吸附值为342.33 mg/g,碘吸附值为1 368.65 mg/g,其BET比表面积达到了1 735.94 m2/g,总孔容积0.36 cm3/g,平均孔径2.33 nm。将此活性炭用于吸附苯酚,苯酚质量浓度60 mg/L的50 mL废水中,当pH值为7,吸附时间2 h,活性炭投放量为50 mg时,苯酚去除率最高可达98%。对此吸附过程进行动力学分析,结果表明准二级动力学模型能很好的描述此活性炭吸附苯酚的过程。 相似文献