超声波辅助不同吸附剂吸附蓝莓渣花色苷效果的比较

采用超声波(20 kHz)辅助四种不同材料(大孔树脂XAD-7HP、酿酒酵母、活性炭、膨润土)吸附蓝莓渣花色苷,比较在水浴振荡和超声波辅助下不同吸附剂对花色苷的吸附效果,研究其吸附动力学过程,进行动力学模型拟合,并采用红外光谱法分析超声波辅助吸附前后吸附剂结构变化,确定在吸附过程中可能发挥作用的官能团。结果表明:超声波辅助下四种吸附剂对花色苷的吸附量均显著高于水浴振荡(P<0.05),吸附量大小:大孔树脂XAD-7HP>活性炭＞膨润土＞酿酒酵母;超声作用下酿酒酵母对花色苷吸附量提高程度最大,提高了19.56%,其余吸附剂按超声作用下吸附量提高程度由大到小依次为膨润土、活性炭和树脂,分别提高了16.48%、11.90%和8.62%;与一级动力学模型相比,Lagergren二级动力学模型能更好地拟合这四种吸附剂对花色苷的吸附过程;傅里叶变换红外光谱分析显示在吸附过程中,大孔树脂表面的酚羟基发生了位移,可能用于形成氢键;酿酒酵母中-COOH和-OH参与了吸附过程,可能发生氢键的位移,多糖和酰胺基团也发挥了作用;活性炭吸附花色苷过程受C=C和C-O影响,O-H变形振动或者-CH₂变形振动也可能参与其中;膨润土在吸附过程中发生了Si-O的变形和弯曲振动,原-OH吸收峰发生移动,这表明膨润土能成功吸附花色苷的原因可能是氢键发生了位移。     

大孔树脂对吡虫啉的吸附性能研究

以大孔树脂为吸附剂,吡虫啉水溶液为吸附对象。研究不同吸附时间、不同药液浓度、不同吸附剂用量对吡虫啉溶液吸附率的影响。研究表明:在6 h内大孔树脂对吡虫啉的吸附达到平衡,吸附速率较快;吸附效率随吡虫啉浓度的增大而减少;随大孔树脂量的增加明显增大。     

大孔树脂对紫玉米花青素的静态吸附与解吸特性研究

为了筛选出对紫玉米花青素粗提液纯化性能好的树脂,采用AB-8型、X-5型、D101型和NKA-9型4种大孔树脂对紫玉米花青素进行静态吸附和解吸实验,研究了大孔树脂对紫玉米花青素的静态吸附动力学曲线,以Langmuir单层吸附方程制定吸附等温曲线,并研究了不同pH条件下对大孔吸附树脂吸附的影响及不同树脂的解吸特性。结果表明:X-5树脂吸附平衡速率常数最大,达到饱和吸附量所用时间最短,经Langmuir单层吸附回归方程预测出X-5树脂静态吸附时最大吸附量可达到53.1915mg/g。在pH=4时,饱和吸附量最大。因而X-5可用做纯化紫玉米花青素较为合适的吸附剂,解吸时宜选用40%乙醇做为洗脱液。     

绿茶微粉对染料亚甲基蓝和孔雀石绿的吸附研究

亚甲基蓝和孔雀石绿是造成水体污染的偶氨工业染料.本文研究在不同的颗粒、pH、吸附剂量、吸附时间条件下绿茶微粉对亚甲基蓝和孔雀石绿的吸附效果,并分析其吸附速率曲线和吸附等温线.结果表明,常温下绿茶微粉能够较好地吸附亚甲基蓝和孔雀石绿,且颗粒越小吸附效果越佳;亚甲基蓝和孔雀石绿最佳吸附pH分别是7和5,吸附饱和量分别是19.37 mg/g和16.50 mg/g.在初始染料质量浓度20 mg/L条件下,240 min左右可达到吸附平衡.吸附动力学分析表明,绿茶微粉对亚甲基蓝和孔雀石绿的生物吸附平衡数据均与拟二级速率方程拟合度较好,吸附规律分别符合Langmuir和Freundlich等温式.     

商业树脂对鲜榨柠檬汁的脱苦效果

以工业生产中鲜榨柠檬原汁为试材,研究了不同商业树脂对鲜榨柠檬汁脱苦效果的影响。结果表明:大孔吸附树脂对柚皮苷和柠檬苦素的吸附率优于离子交换树脂,且对营养成分的影响较小;优选出的大孔吸附树脂R6在达到吸附平衡时对柚皮苷和柠檬苦素的吸附率最大,分别达82.87%和69.13%,且吸附时间较短,其对柚皮苷和柠檬苦素的吸附等温线分别与Langmuir经典方程式和Freundlich经典方程式拟合度最好,具有良好的静态吸附性能。     

玉米芯吸附处理工业废水中染料的方法研究

以玉米芯为原料制备活性炭吸附剂,研究其对次甲基蓝、碱性品红、甲基橙三种染料废水的吸附性能。考察了温度、吸附剂量、吸附时间等因素对吸附效果的影响。结果表明,在吸附剂量为1g,吸附时间在5h左右,温度为70℃时玉米芯吸附剂对三种染料达到最佳吸附效果。吸附率与时间的吸附动力学方程说明吸附过程有很好的线性关系。玉米芯活性炭作为染料废水吸附剂具有很好的开发应用前景。     

浓香型原酒中塑化剂的吸附剂筛选

选用4种大孔树脂和4种酒类专用活性炭为吸附剂,采用静态吸附法,首先对57%酒精度模拟加标酒样进行吸附实验,以邻苯二甲酸二甲酯(dimethyl phthalate,DMP)、邻苯二甲酸二异丁酯(diisobutyl phthalate,DIBP)、邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)、邻苯二甲酸二(2-乙基)己酯(diethylhexyl phthalate,DEHP)4种邻苯二甲酸酯类塑化剂的吸附率为指标进行初选。之后用57%酒精度浓香型原酒进行验证,以塑化剂的吸附率和原酒中己酸乙酯、乙酸乙酯、乳酸乙酯、丁酸乙酯4种香气成分的损失率作为指标,筛选出理想的吸附剂。结果表明:1)JT201、JT203酒类专用活性炭对模拟酒样中4种塑化剂的吸附效果较好,平均吸附率为91.01%和87.21%,大孔树脂中非极性的D4006较其他树脂吸附效果好,吸附率达73.67%;极性大孔树脂NKA-Ⅱ和颗粒活性炭的吸附率不足60%,初选JT201、JT203酒类专用活性炭为原酒中塑化剂的吸附剂。2)JT201、JT203酒类专用活性炭吸附后,原酒中DMP、DBP的去除率均达90%以上,JT201对DIBP、DEHP的去除率均达80%以上,JT203对DIBP、DEHP去除率为78%、72%;JT201、JT203吸附处理后原酒中己酸乙酯、乙酸乙酯、乳酸乙酯、丁酸乙酯分别损失7.7%、6.1%、11.9%、11.6%和10.4%、8.6%、33.9%、16.0%,本研究确定JT201酒类专用活性炭为去除浓香型原酒中塑化剂的最佳吸附剂。     

吸附法处理印染废水的研究进展

文章主要介绍活性炭、树脂、矿物和废弃物吸附印染废水中染料分子的过程,并对三类吸附剂的优点和缺点进行了对比。活性炭的吸附能力与其表面积和孔径大小有关,因其多孔的结构能够高效吸附染料分子,但其再生方法仍存在一定的局限性;树脂的吸附能力与其孔径大小和其上面的功能基有关,弱碱性的离子交换树脂能够高效吸附染料分子,染料分子也易从其上面洗脱,这有利于树脂的再生利用,但印染废水中的无机盐会对树脂吸附染料分子的过程产生抑制作用;矿物和废弃物的吸附能力与其孔径大小和染料分子的性质有关,天然矿物储量丰富,废弃物价格低廉,用其处理印染废水节约了成本,但矿物和废弃物中的重金属等污染物因条件调节不当会溶出,造成二次污染。通过比较三类吸附剂发现,利用天然矿物和废弃物处理染料分子不仅节约成本,还能利用自身的酶分解染料分子,实现再生,此方法具有广阔的应用前景。     

酚醛基活性炭纤维的制备及其对亚甲基蓝染料溶液的吸附性能研究

以酚醛纤维为原料,采用水蒸气活化法进行物理活化,制备具有丰富微孔结构的酚醛基活性炭纤维,并以亚甲基蓝染料溶液作为吸附质,探讨吸附时间、吸附温度、染料溶液初始浓度对其吸附性能的影响,同时对其吸附平衡、吸附动力学进行研究。结果表明:酚醛基活性炭纤维对亚甲基蓝染料分子的吸附性较好,吸附时间、吸附温度及染料溶液初始浓度均对吸附性能有较大影响;吸附过程符合Langmuir吸附等温线模型和准二级动力学模型,表明酚醛基活性炭纤维对亚甲基蓝染料分子的吸附属于单分子层吸附,且吸附过程以化学吸附为主导。     

黄麻纤维活性炭对亚甲基蓝和甲基橙溶液的吸附性能研究

以黄麻纤维为原料,采用磷酸活化法制得黄麻纤维活性炭作为吸附剂,以纺织印染加工中较为常用的亚甲基蓝(MB)和甲基橙(MO)染料溶液为吸附质,研究染料溶液初始浓度、活性炭投加量、吸附时间等因素对黄麻纤维活性炭吸附性能的影响。结果表明:随着染料溶液初始浓度的增加,两种染料的去除率逐渐降低,吸附量逐渐增大;随着活性炭投加量的增加和吸附时间的延长,两种染料的去除率和吸附量均呈现逐渐增大的变化规律;水浴温度对两种染料的去除率和吸附量影响都较小;染料溶液pH值对两种染料吸附性能的影响存在较大差异,MB的去除率和吸附量随染料溶液pH值增加而增大,而MO的去除率和吸附量随之减小。     

基于吸附理论分析活性炭对卷烟烟气的吸附

为了解活性炭孔隙结构及被吸附化合物的性质对吸附效率的影响,测定了纯丙酮气体在活性炭上的吸附特性及不同结构活性炭对烟气羰基物的吸附效率。分别用Langmuir模型和D-R模型对活性炭上丙酮气体的吸附数据进行拟合,从模型拟合精度及吸附热预测角度对Langmuir模型及D-R模型进行了比较。进一步分析了吸附效率与模型参数间的关系以及模型参数与活性炭结构和被吸附化合物性质间的关系。结果表明:①与Langmuir模型相比,D-R模型对活性炭上纯丙酮气体吸附数据的拟合相关系数更高,平均相对标准偏差更低,拟合结果更好。②由10-4-3型势函数计算得到活性炭上纯丙酮气体的理论吸附热为17.9 kJ/mol,吸附热较小,说明此吸附以物理吸附为主。D-R模型吸附热预测值为15.8 kJ/mol,与理论计算值较为接近;Langmuir模型吸附热预测值为40.7 kJ/mol,比理论计算值偏大较多。③实现活性炭对不同化合物吸附效率预测的关键是对化合物吸附热的预测。吸附效率主要与吸附温度,活性炭的用量、孔容,化合物的分子量,碰撞直径和能量参数有关。通过分析吸附能可以推断孔径对吸附效率及吸附选择性的影响。     

颗粒活性炭对模拟活性染料废水的吸附脱色效果

本文借助SEM观察了颗粒活性炭的表面形态结构,利用紫外-可见分光光度计测试分析了模拟染料废水吸附前后的吸光度变化,以考察颗粒活性炭种类、目数、染料废水浓度、pH值、吸附温度及时间对染液吸附脱色效果的影响。实验结果表明：椰壳活性炭的吸附脱色效果较煤质、果壳活性炭好;活性炭目数越大,其吸附脱色效果越好;活性炭对染料废水的吸附脱色效果随染料浓度的增大而呈线性函数下降;酸性环境下活性炭的吸附脱色效果好于碱性环境,pH值为5.5时,吸附脱色效果最好;吸附温度越高,脱色率越高,但升至一定温度后对吸附脱色效果增加不再显著;达平衡吸附前,增加吸附时间对活性炭的吸附脱色效果增加较为显著。     

聚硅酸镁铁的制备及对水溶性染料废水处理

水溶性染料废水是印染废水中较难处理的一部分。采用合成的聚硅酸镁铁，利用吸附和混凝两种作用，其脱色效果高于粉末活性炭等其他吸附剂。试验表明，聚硅酸镁铁合成药剂投加量为1g/L、pH值11时，大部分水溶性染料废水经脱色后，色度接近于0。     

Effect of strongly competing background compounds on the kinetics of trace organic contaminant desorption from activated carbon

Strongly competing (SC) compounds, naturally found in any drinking water source, are known to decrease the adsorption capacity of activated carbon for trace contaminants. While the effect of these substances on the capacity and adsorption kinetics of trace contaminants is fairly well studied, relatively little is known about their impact on desorption kinetics. The purpose of this study was to investigate the relationship between SC matter and trace compound desorption kinetics. A surrogate SC compound, 1,4-dichlorobenzene (p-DCB), was used to displace the preadsorbed target trace contaminant, atrazine, from powdered activated carbon (PAC). The initial concentrations of p-DCB and atrazine were varied to achieve different degrees of competition to atrazine. Atrazine's desorption diffusion coefficient was found to increase with increasing adsorbed concentration of the SC matter, expressed as an equivalent background compound (EBC).The EBC was modeled with atrazine-like adsorption properties, thus representing the portion of p-DCB that competed to occupy atrazine adsorption sites. The increase in atrazine diffusion rate can be explained by a shift from surface diffusion to diffusion through the carbon's pores as the availability of surface sites decreased due to the EBC's competition. The observed desorption kinetic relationship was consistent with the effect of SC competition on adsorption kinetics; further, the effect was consistent for three different types of SC matter. These findings highlight that the impact of SC matter on activated carbon applications could be either detrimental (displacing adsorbed trace contaminants and enhancing their rate of release) or beneficial (offsetting pore constriction effects by enhancing their rate of uptake).     

Removal of methylene blue from aqueous media using activated carbon web

Activated carbon web is prepared by controlled pyrolysis of acrylic fibrous waste under the layer of charcoal using physical activation in high-temperature furnace. The carbonization was carried out at 1200 °C under different heating rate (i.e. 150 to 450 °C h^?1) with different holding time (i.e. 0 to 60 min) to decide optimum pyrolysis parameters. The heating rate of 300 °C h^?1 with no holding time revealed higher specific surface area of 280 m² g^?1. The prepared activated carbon web was later employed as adsorbent for removal of methylene blue from aqueous media. The effect of initial dye concentration, adsorbent dosage, stirring speed, and pH of solution was studied. The obtained results were later compared with adsorption isotherms (i.e. Langmuir and Freundlich). The Freundlich model was found to fit closely with results due to heterogeneous adsorption of dye molecules. Finally, virgin activated carbon and dye adsorbed activated carbon were tested for desorption behavior using differential scanning calorimetry and thermo gravimetric analysis. The significant reduction in desorption enthalpy from 172.46 to 52.43 J g^?1 is attributed to less adsorption energies of dye molecules on the surface of activated carbon due to nonhomogeneous distribution of active sites.     

The Dehydration of Fructose Towards 5-Hydroxymethylfurfural Using Activated Carbon as Adsorbent

5-Hydroxymethylfurfural (HMF) can be selectively adsorbed onto activated carbon with loadings up to 30% (w/w), depending on the type of carbon used. Adsorption isotherms of HMF on several types of carbon and in different solvents are presented. Activated carbon is used in in the dehydration of fructose towards HMF in order to suppress the formation of side-products (e. g. levulinic acid). A dehydration set-up in which the formation and adsorption of HMF take place at different temperatures is presented. The HMF is recovered by extraction of the loaded activated carbon with organic solvent.     

甲醇钠及原甲酸三甲脂尾气达标排放探讨

内蒙古兰太实业股份有限公司兰峰分公司生产产品主要有甲醇钠和原甲酸三甲脂,这两种产品生产过程中都产生尾气,尾气的主要成分是氢气和甲醇气体,由于甲醇气体为有毒有害气体,排放到大气中后会对环境造成污染,因此为了响应国家节能减排号召,对氢气中的甲醇进行阻截吸附,通过前期的实验,确定了吸附工艺——活性炭吸附工艺,此工艺原理为来自甲醇钠（原甲酸三甲脂）车间的含甲醇排空氢气,自吸附塔下部进入塔内,含甲醇氢气被第一层活性炭吸附,再进入第二层活性炭二次吸附,使甲醇被活性炭吸附,达到环评报告排放要求61.63 mg/m3,再通过管道阻火器后排空。经过此次改造,兰峰分公司甲醇钠和原甲酸三甲脂产生的尾气实现了达标排放,改善了环境,取得了良好的社会效益,同时为节能减排工作做出了很大的贡献。     

Adsorption characteristics of SO2 on activated carbon prepared from coconut shell with potassium hydroxide activation

The adsorption characteristics of SO2 were studied with KOH-impregnated granular activated carbon (K-IAC). To confirm selective SO2 adsorptivity of K-IAC using a fixed bed adsorption column, experiments were conducted on the effects of KOH and of linear velocity, temperature, and concentration. In addition, changes in features before and after adsorption were observed by utilizing FTIR, XRD, ToF-SIMS, and AES/SAM, examining the surface chemistry. K-IAC adsorbed 13.2 times more SO2 than did general activated carbon (GAC). The amount of SO2 adsorbed increased as linear velocity and concentration increased and as temperature decreased. At lower temperature, the dominant reaction between KOH and SO2 produces K2-SO3 and H2O. Any H2O remaining on the surface is converted into H2SO4 as SO2 and O2 are introduced. Then, the KOH and SO2 reaction produces K2SO4 and H2O. The surface characterization results proved that adsorption occurred through chemical reaction between KOH and SO2. The SO2 adsorbed K-IAC exists in the form of stable oxide crystal, K2SO3 and K2SO4, due to potassium. The basic feature given to the surface of activated carbon by KOH impregnation was confirmed to be acting as the main factor in enhancing SO2 adsorptivity.     

Displacement effect of NOM on atrazine adsorption by PACs with different pore size distributions

This study investigated displacement of atrazine by the strongly competing fraction of natural organic matter (NOM) in batch and continuous-flow powdered activated carbon/PAC) adsorption systems. Due to the displacement effect, atrazine adsorption capacity in a continuous flow PAC/microfiltration (MF) system, where the carbon retention time is greater than the hydraulic retention time, decreased with time or NOM throughput. The capacity was lower than that measured in a batch reactor or predicted by the equivalent background compound-ideal adsorbed solution theory (EBC-IAST) method. A mathematical model previously developed to simulate the adsorption process in the PAC/MF system was modified to take into account the displacement effect. Two types of PACs were tested using a range of influent atrazine concentrations and carbon doses. The extent of atrazine displacement by NOM was found to depend on the type of PAC, while the rate of displacement was a function of PAC type as well as carbon dose. The PAC lost its adsorption capacity for atrazine faster at a lower carbon dose. PAC B, which has a higher percentage of mesopores, lost more atrazine adsorption capacity but at a slower rate than PAC A.