羧基酯化改性花生壳对染料废水的吸附

通过甲醇酯化法制备改性花生壳,用于吸附刚果红、次甲基蓝染料废水.考察了吸附时间、溶液pH值、初始浓度对吸附的影响及改性花生壳的再生.结果表明,在室温、刚果红在pH值4.16、次甲基蓝在7.45时,吸附效果最佳,经搅拌吸附120 min达到平衡,两染料最大吸附率分别为82.30％和90.84％,饱和吸附量分别为10.88 mg/g和11.82 mg/g.吸附符合一级动力学过程和Langmuir等温吸附模型.改性花生壳吸附效果较未改性花生壳明显提高,且可经0.5 moL/L NaOH溶液再生重复使用.     

酯化改性花生壳吸附水中Cr（Ⅵ）的研究

研究了乙酸酯化改性花生壳在不同的pH值、不同温度、不同的用量等条件下对Cr（Ⅵ）的吸附情况。结果表明,酯化改性花生壳对Cr（Ⅵ）有很强的吸附能力,在60 min内可以迅速达到吸附平衡,最大去除率可达98.7%,溶液的pH对吸附特性有较大影响,最佳吸附pH为1左右;吸附温度对吸附影响不大,升高温度吸附去除率略有上升。     

花生壳活性炭对Cu~(2+)的吸附性能研究

以花生壳为原料,磷酸为活化剂制备花生壳活性炭,采用高分辨电子扫描电镜(SEM)对花生壳活性炭进行了表征。从热力学和动力学的角度,研究了花生壳活性炭对Cu2+的吸附行为。热力学研究表明:花生壳活性炭对Cu2+的吸附符合Langmuir等温吸附方程,该吸附是自发吸热过程。动力学研究表明:花生壳活性炭对Cu2+的吸附符合二级反应动力学方程反应特征,颗粒内扩散为主要控速步骤。     

硝酸改性花生壳对含铊废水的吸附性能研究

采用硝酸改性花生壳对模拟含铊废水进行吸附,研究了p H、反应时间、吸附温度对改性花生壳吸附Tl+的影响及其吸附特性。结果表明,p H对吸附有较大影响,吸附适宜p H为6~7,改性花生壳对Tl+的吸附遵从准二级动力学模型。     

改性花生壳吸附亚甲基蓝动力学与机理研究

吸附法是去除水中有机污染物的一种重要方式.以农业废弃物花生壳为原料,通过稀酸改性制备对亚甲基蓝吸附性能良好的生物质基吸附材料.FT-IR分析表明改性花生壳表面含有羟基、羧基等有利于吸附的官能团,SEM和孔结构分析结果显示稀硫酸改性花生壳表面形成大量孔结构.亚甲基蓝浓度为100 mg/L时,改性花生壳的去除效率为91.5...     

改性花生壳吸附水中Cr6+的研究

研究了改性花生壳对Cr6 的吸附作用,并探讨了溶液的pH值、Cr6 初始浓度、吸附时间、温度及改性花生壳用量等因素对Cr6 吸附效果的影响.结果表明,在温度为33℃、改性花生壳用量为1.0 g、20 mg·L-1的Cr6 溶液50 mL、溶液的pH值为2.0、振荡吸附时间为120 min的条件下,Cr6 的吸附去除率达到了98.4%.     

改性花生壳活性炭吸附空气中甲醛性能的研究

研究了碳酸钠/亚硫酸氢钠、氢氧化钠和过氧化氢改性的花生壳活性炭对空气中甲醛吸附性能的影响,并通过X射线衍射、傅里叶红外光谱、元素分析和扫描电镜等技术对改性花生壳活性炭结构进行表征。结果表明,经碳酸钠/亚硫酸氢钠、氢氧化钠和过氧化氢改性后的花生壳活性炭,在吸附120min时,其对空气中甲醛去除率分别比未改性花生壳活性炭提高了9.01%、2.54%和6.79%。通过对活性炭结构的表征发现,经碳酸钠/亚硫酸氢钠改性后的花生壳活性炭的甲醛吸附性能最高的原因一方面可能与亚硫酸氢钠与甲醛发生了化学反应有关,另一方面也可能与活性炭晶体结构变化、活性炭比表面积增大和活性炭表面的含氧官能团的增大有关。该研究在花生壳的综合利用、减少环境污染及室内甲醛的去除方面具有重要的现实意义。     

改性花生壳对活性黄的吸附性能研究

以甲醛和硫酸改性处理后的花生壳作为生物质吸附剂,对活性黄染料溶液吸附脱色性能进行了研究。考察了溶液的pH值、溶液的初始浓度、温度、吸附剂的用量及大小、吸附时间及溶液中的盐离子浓度等对吸附效果的影响,并对吸附动力学和热力学进行研究。结果表明,改性的花生壳吸附活性黄的最佳条件为:在染料浓度100mg/L、吸附剂的用量10 g/L、pH值为2.0、吸附时间在240 min的条件下,改性花生壳对活性黄的吸附率可达到99%以上;Langmuir型吸附模型能较好地描述改性花生壳对活性黄的吸附实验数据,该吸附过程符合准二动力学吸附模型,且吸附过程的Gibbs自由函数ΔG0,反应活化能Ea=20.60 kJ/mol,吸附反应可以自发进行。     

柠檬酸改性花生壳对水中重金属Cu、Pb、Cd和Cr的吸附特性研究

用柠檬酸对粒状花生壳进行改性,考察了改性粒状花生壳的投加量、吸附反应时间、重金属初始浓度等对水中Cu、Pb、Cd和Cr吸附量的影响,探讨了改性粒状花生壳的等温吸附及吸附动力学特性。结果表明,准二级吸附动力学方程可较好地模拟Cu、Pb、Cd和Cr等4种重金属在改性粒状花生壳上的吸附动力学行为;Langmuir模型能相对更好地拟合改性粒状花生壳对4种重金属的等温吸附过程,Cu、Pb、Cd和Cr的理论最大吸附量分别为11.88,20.70,7.82,7.35 mg/g。改性粒状花生壳与Pb的结合力最强,对Pb的吸附容量远大于其它3种重金属。     

花生壳吸附溶液中铀的研究

以废弃物花生壳为吸附剂来吸附水溶液中的铀,研究了花生壳加入量、溶液pH、铀初始质量浓度以及吸附时间等因素对铀吸附效果的影响。结果表明,花生壳对铀具有较好的吸附效果,当pH=4.0、花生壳用量为4 g.L-1、粒径为0.15～0.3 mm、铀初始质量浓度为30 mg.L-1、吸附时间为2.0 h时,铀的去除率达到了97.8%。等温吸附研究表明,花生壳对铀的吸附行为更符合Langmuir等温吸附方程,说明花生壳对铀的吸附是以单分子层吸附(化学吸附)为主,通过拟合得出最大吸附量为5.05 mg.g-1。     

高铁酸钾降解铬黑T和铬蓝黑R的研究

采用高铁酸钾对水溶性铬黑T和铬蓝黑R废水进行氧化脱色研究,考察高铁酸钾用量、反应温度和染料质量浓度对脱色率的影响。结果表明,高铁酸钾能够有效去除染料废水的色度,高铁酸钾用量和反应温度均存在最佳值。铬黑T和铬蓝黑R的质量浓度低于100mg/L时,脱色率均可达到87%以上。     

NaOH改性花生壳对亚甲基蓝染料吸附性能的研究

花生壳用5%的NaOH溶液改性作吸附剂处理亚甲基蓝染料废水,考察pH值、吸附剂投加量、染料浓度和温度及吸附时间对染料吸附性能的影响。结果表明,吸附最佳的工艺条件为:温度25℃,吸附剂投加量0.3 g,亚甲基蓝的初始浓度3.5 g/mL,反应时间135 min,pH值7。此时改性花生壳对亚甲基蓝的吸附率达99.57%。     

Sorption of remazol brilliant blue R onto polyurethane‐type foam prepared from peanut shell

The powders of peanut shell is first liquefied with the mixture of polyethylene glycol‐400 and monoethylene glycol (MEG) using sulfuric acid at 160°C for 2 h. Polyurethane (PU)‐type rigid foam is prepared from the reaction between peanut shell liquefied with the MEG and diphenylmethane diisocyanate. Then the PU foam is used as a sorbent for the removal of the remazol brilliant blue R from aqueous solution. The sorption of the dye increases with increasing initial concentration, temperature, and ionic strength, while decreasing with increasing pH. From the isotherm and kinetic studies, it is seen that the sorption process is in the best agreement with the Langmuir isotherm and the pseudo second‐order kinetic model. Desorption and FTIR studies show that a chemisorption process occurs between dye and foam, probably indicating electrostatic interactions. The thermodynamic parameters (i.e., standard free energy, standard enthalpy, and standard entropy) are determined, and the results obtained are discussed in detail. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013     

乳液法制备石墨烯气凝胶及其吸附水中亚甲基蓝

利用乳液法制备多孔石墨烯气凝胶（emGA）,改变乳液油水比制备不同的emGA。扫描电子显微镜（SEM）、傅里叶红外光谱（FTIR）、氮气吸附脱附等表征显示,emGA具有多孔结构,经水热还原后含氧官能团大部分被除去,比表面积为103.3～243.1m²/g。以亚甲基蓝（MB）浓度和温度作为变量,考察emGA对水中MB的吸附效果。结果表明,emGA的比表面积越大,其对MB平衡吸附量越大;当初始浓度越大,温度越高,则吸附有利。吸附动力学数据表明emGA吸附MB符合准二级动力学模型和内扩散模型,吸附过程分为大孔扩散和微孔扩散。吸附等温线数据拟合结果符合Langmuir模型,表明emGA对MB的吸附属于单分子层吸附。Langmuir模型计算出emGA-2饱和吸附量为307.7mg/g,与实验值291.3mg/g较为接近。分析热力学参数发现,emGA吸附MB为自发吸热过程,且吸附过程属于物理吸附。     

The removal of cationic dyes from aqueous solutions by adsorption onto pistachio hull waste

The efficacy of pistachio hull powder (PHP) prepared from agricultural waste was investigated in this study as a novel adsorbent for the elimination of dye molecules from contaminated streams. Removal of methylene blue (MB) as a cationic model dye by PHP from aqueous solution was studied under different experimental conditions. The selected parameters were solution pH (2–10), PHP dosage (0.5–3 g/L), MB concentrations (100–400 mg/L), contact time (1–70), and solution temperature (20–50 °C). The experimental results indicated that the maximum MB removal could be attained at a solution pH of 8. The dosage of PHP was also found to be an important variable influencing the MB removal percentage. The removal efficiency of MB improved from 94.6 to 99.7% at 70 min contact time when the MB concentration was decreased from 300 to 100 mg/L at a pH and PHP dosage of 8 and 1.5 g/L, respectively. The kinetic analysis showed that the pseudo-second-order model had the best fit to the experimental data. The Langmuir equation provided the best fit for the experimental data of the equilibrium adsorption of MB onto PHP at different temperatures. In addition, the maximum adsorption capacity increased from 389 to 602 mg/g when the temperature was increased from 20 to 50 °C. The thermodynamic evaluation of MB adsorption on PHP revealed that the adsorption phenomenon under the selected conditions was a spontaneous physical process. Accordingly, pistachio hull waste was shown to be a very efficient and low-cost adsorbent, and a promising alternative for eliminating dyes from industrial wastewaters.     

花生壳制活性炭及其脱六价铬研究

本文研究了用花生壳制备活性炭和用此活性炭去除水溶液中的Cr（Ⅵ）。采用化学活化法,即用H2SO4、H3PO4、ZnCl2、KOH活化花生壳中的炭。同时研究了这些活化剂的浓度和用量、热解时间和温度对活性炭性能的影响。采用亚甲基蓝吸附实验评价活性炭的性能。结果表明H3PO4和ZnCl2是良好的活化剂,KOH和H2SO4效果较差。溶液的pH值对活性炭吸附Cr（Ⅵ）的能力有很大影响。活性炭的吸附能力随着pH值的降低而升高,同时在不同的pH值下,炭的吸附速率也不同。pH值越低,Cr（Ⅵ）被吸附的越快。等温实验结果表明,在pH值等于2时,用H3PO4和ZnCl2活化的活性炭对Cr（Ⅵ）的吸附能力分别达到125．0和83．3mg·g^-1。花生壳活性炭吸附Cr（Ⅵ）的机理比较复杂,与溶液的pH值有关。在pH值等于2时,等温吸附可以用Langmuir模型模拟;在pH值等于2～7时,可以用Freundlich模型模拟。     

超声波辅助粉煤灰去除水中亚甲基蓝染料的动力学分析

为了开发更多的粉煤灰用途,采用粉煤灰去除水中的染料污染物,达到以废治废的目的。采用超声波辅助粉煤灰的方法,以亚甲基蓝染料作为模拟污染物,考察此工艺的可行性,讨论亚甲基蓝的去除效果,分析其动力学。研究结果证明,超声波-粉煤灰联合体系（US-FA体系）具有良好的去除染料污染物的能力,超声波的引入能提高粉煤灰对染料污染物的去除率,协同效应非常明显,粉煤灰投加量0.3、0.5、1.0和2.0 g的情况下,协同因子分别达到1.05、1.32、1.55和2.27。在本实验体系内,经过恒温控制后,超声波的热效应可以忽略,主要通过粉煤灰吸附和羟基自由基降解两大主要途径去除污染物,超声波对去除性能的促进作用主要体现在以下几个方面：一是超声波空化作用产生羟基自由基,超声波和粉煤灰表面相互作用产生更多的羟基自由基;二是超声波能促进粉煤灰表面产生更多的活性位,促进了吸附过程的化学反应步骤,由于粉煤灰对亚甲基蓝的吸附过程以化学反应为控制步骤,所以超声波能大为促进粉煤灰的吸附性能;三是超声波的引入加剧了固液混合,促进污染物向固相表面移动,促进更多的污染物进入到吸附剂颗粒内部,改善了传质。     

Removal of methylene blue from aqueous solution by adsorption onto zeolite synthesized from coal fly ash and its thermal regeneration

BACKGROUND: The removal of cationic dyes from wastewater is of great importance. Three zeolites synthesized from coal fly ashes (ZFAs) were investigated as adsorbents to remove methylene blue (MB), a cationic dye, from aqueous solutions. Experiments were conducted using the batch adsorption technique under different conditions of initial dye concentration, adsorbent dose, solution pH, and salt concentration. RESULTS: The adsorption isotherm data of MB on ZFAs were fitted well to the Langmuir model. The maximum adsorption capacities of MB by the three ZFAs, calculated using the Langmuir equation, ranged from 23.70 to 50.51 mg g^?1. The adsorption of MB by ZFA was essentially due to electrostatic forces. The measurement of zeta potential indicated that ZFA had a lower surface charge at alkaline pH, resulting in enhanced removal of MB with increasing pH. MB was highly competitive compared with Na⁺, leading to only a < 6% reduction in adsorption in the presence of NaCl up to 1.0 mol L^?1. Regeneration of used ZFA was achieved by thermal treatment. In this study, 90–105% adsorption capacity of fresh ZFA was recovered by heating at 450 °C for 2 h. CONCLUSION: The experimental results suggest that ZFA could be employed as an adsorbent in the removal of cationic dyes from wastewater, and the adsorptive ability of used ZFA can be recovered by thermal treatment. Copyright © 2010 Society of Chemical Industry     

分子印迹固相萃取法提取花生壳中木犀草素

采用分子印迹技术,以木犀草素为模板分子、丙烯酰胺为功能单体、EGDMA为交联剂,合成了木犀草素印迹聚合物。将该印迹聚合物用于固相萃取,分离提取花生壳中的木犀草素。结果表明,该印迹聚合物对木犀草素具有较高的吸附性能和选择性,用印迹柱萃取得到的木犀草素纯度高出硅胶柱分离近20个百分点,达到96.2%。且MIPs-SPE柱与普通的硅胶柱相比,经过洗脱再生后可以反复使用多次。