壳聚糖树脂对染料动态吸附性能研究

以甲醛-环氧氯丙烷为交联剂,采用反向悬浮法制备交联壳聚糖树脂,主要研究了固定床吸附中壳聚糖树脂对酸性橙Ⅱ和C.I.活性蓝19的吸附性能,考察了进口处染液浓度和流速对穿透曲线的影响,同时对壳聚糖树脂再生方法和重复利用性能进行了研究。实验结果表明:染料溶液浓度越高、进样流速越快,穿透时间、吸附终点时间越短,但对应的吸附柱的吸附终点吸附量降低;确定壳聚糖树脂的最佳再生条件为氢氧化钠浓度0.5 mol/L,再生时间0.5 h;0.5 g壳聚糖树脂,5次再生后壳聚糖树脂再生吸附率仍高达84%。     

交联淀粉对孔雀石绿吸附性能研究

制备了羧甲基交联淀粉作为吸附剂,研究了其对孔雀石绿(MG)的吸附性能,进行最佳条件的探讨。考察了吸附接触时间、pH值、交联淀粉的投加量、孔雀石绿的初始染料浓度和不同温度变化对交联淀粉吸附MG的影响,并对吸附等温式和吸附动力学方程等进行了分析。结果表明,高温更利于交联淀粉吸附MG。吸附等温式和吸附动力学过程更符合Freundlich吸附等温式和准二级动力学模型,最大吸附量q_m为769.23 mg/g(298 K)。     

改性壳聚糖对茜素红、活性红的脱色研究

以戊二醛作为交联剂,氯化铝、二氧化钛为掺杂剂对壳聚糖进行交联聚合改性,制备改性壳聚糖,通过IR、XRD的表征和等温吸附曲线确定掺杂二氧化钛、氯化铝的交联壳聚糖具有较好的吸附效果,再通过正交实验研究温度、染料浓度、时间、吸附剂用量等因素对该改性壳聚糖吸附茜素红、活性红的影响,试验结果表明:用该改性壳聚糖吸附茜素红,当茜素红浓度为40mg/L,温度为35℃,改性壳聚糖用量为1.5g,吸附时间为20min,脱色率91.1%,CODCr去除率79.1%;当活性红浓度为40mg/L,温度为20℃,改性壳聚糖用量为2.0g,吸附时间为30min,脱色率99.9%,CODCr去除率82.2%.     

掺杂TiO_2壳聚糖对茜素红、活性红的脱色研究

以戊二醛作为交联剂,二氧化钛为掺杂剂对壳聚糖进行交联聚合改性,制备掺杂TiO2交联壳聚糖(TiO2-CCTS),利用IR、XRD对TiO2-CCTS表征,绘制吸附等温曲线,吸附等温曲线符合Freund lich方程式,即α=0.02C1/n。通过正交实验研究温度、染料浓度、时间、吸附剂用量等因素对TiO2-CCTS吸附茜素红、活性红的影响,结果表明,当茜素红浓度为40 mg/L,温度20℃,TiO2-CCTS用量为2.0 g,吸附时间30 m in,脱色率94.2%,CODC r去除率79%;当活性红浓度为40 mg/L,温度20℃,TiO2-CCTS用量为1.0 g,吸附时间10 m in,脱色率99.2%,CODC r去除率85%。     

交联壳聚糖多孔微球吸附亮绿的研究

利用液体石蜡作有机分散介质,戊二醛作交联剂,制备了交联壳聚糖多孔微球,采用SEM对壳聚糖微球的形貌、大小进行了表征,研究交联壳聚糖微球对亮绿的吸附性能,探讨交联壳聚糖多孔微球用量、亮绿初始浓度、pH值、吸附时间、吸附温度的影响.结果表明,室温下,交联壳聚糖微球粒径为0.5～1.0 mm,亮绿初始浓度10 mg·L-1,pH=6,振摇30 min时,吸附量达1.22 mg·g-1;CODCr去除率达73%.亮绿初始浓度越大,吸附量越大,吸附速率越大;吸附剂用量越大,平衡吸附量越小,吸附速率越大.交联壳聚糖微球对亮绿具有很高的吸附容量和较快的吸附速率,再生重复使用,其脱色率仍达90%以上.等温吸附较好符合Freundlich方程.     

活性染料在D201大孔树脂上的脱色性能

研究了活性染料KN-B,K-2BP和KN-R在D201大孔树脂上的吸附特性.结果表明,3种染料的吸附脱色率均随初始pH值降低、温度升高、染料初始浓度降低、树脂用量增加及NaCl浓度提高而增加.在pH=7和温度298K条件下,3种染料在D201上的等温吸附规律均符合Freundlich和Langmuir模型,最大饱和吸附量分别为129.38,94.79和133.28mg/g,吸附为物理性自发吸附过程.动力学实验数据用准一级和准二级模型方程处理,准一级拟合比准二级拟合更接近实验值,相同条件下3种活性染料在D201上的吸附效果为KN-RKN-BK-2BP.     

交联羧甲基壳聚糖树脂对稀土离子吸附性能研究

以羧甲基壳聚糖为原料，经戊二醛交联制备阳离子型树脂，考察了其对稀土离子La^3 、Nd^3 、Sm^3 、Lu^3 吸附性能。探讨了溶液的酸度、体系温度、初始离子浓度及离子强度对该树脂吸附性能的影响；发现羧甲基壳聚糖经戊二醛交联制成的树脂对稀土离子有较强的吸附性，最高吸附率可达99％以上，并且具有良好的重复使用性；其吸附性为满足Langmuir或Freumdilich等温式。     

羧甲基壳聚糖微球对曙红Y的吸附研究

以壳聚糖粉末为原料,戊二醛进行交联、羧甲基化,制得羧甲基壳聚糖微球。采用SEM对壳聚糖微球的形貌、大小进行了表征,研究羧甲基壳聚糖微球对曙红Y的吸附性能。探讨吸附剂用量、吸附时间、曙红Y的初始浓度、pH、温度对脱色率的影响,研究吸附等温曲线和动力学方程。实验结果表明,曙红Y初始浓度增加时,吸附量也增加,直到吸附饱和,羧甲基壳聚糖的饱和吸附量为75 mg/g;相同条件下,吸附剂用量增加时,平衡吸附量减小,去除率增加。298 K,吸附剂投加量为1 g,pH=7.0,吸附时间为40 min时,初始浓度为560 mg/L的曙红Y染料的去除率可以达到90%以上。符合Langmuir等温方程和二级吸附动力学方程。     

掺TiO2壳聚糖对活性红脱色的正交试验

通过正交试验方法,用掺TiO2壳聚糖对活性红进行脱色实验.对脱色的影响因素,如脱色温度、活性红浓度、脱色时间、掺TiO2壳聚糖用量进行探讨,确定影响脱色效果的主次因素顺序.绘制吸附等温曲线,吸附等温曲线符合Freundlich方程式,即α=0.02C0.83.     

可再生羧甲基壳聚糖树脂的制备及对Eu(Ⅲ)离子吸附性能的研究

以羧甲基壳聚糖为原料，经戊二醛交联，制备阳离子型树脂。考察了其对稀土离子Eu^3 的吸附性能，探讨了溶液的酸度、初始离子浓度、反应时间及离子强度对该树脂吸附性能的影响；发现羧甲基壳聚糖经戊二醛交联制成的树脂对Eu3^ 有较强的吸附性能，可达到95％且吸附速度快，并且具有良好的使用性。     

Evaluation of polystyrene anion exchange resin for removal of reactive dyes from aqueous solutions

The Amberlite IRA-900 resin was tested to remove C.I. Reactive Black 5, C.I. Reactive Red 2 and C.I. Reactive Red 120 dyes from solutions. Batch adsorption studies concerning effects of the phase contact time, pH, temperature, the presence of salts and surfactants were run. A pseudo second-order kinetic model was used to evaluate the rate constants. The Langmuir equation provided good fit for the experimental data of the equilibrium adsorption. The studies of dyes uptake using the dynamic method were run. The treatment efficiency of Amberlite IRA-900 to model wastewaters was tested. Desorption experiments by the batch method were performed.     

季铵型阳离子聚丙烯酰胺的无盐染色行为

以季铵型阳离子聚丙烯酰胺作为一种新的阳离子助剂对棉纤维进行处理,应用于活性染料无盐染色,对染色过程中染料与处理后棉纤维之间的吸附类型、吸附热力学及吸附动力学进行了研究。结果表明,无盐染色过程符合Langmuir吸附模型;吸附过程是放热自发进行的,低温有利于染料的吸附;吸附动力学符合二级动力学模型,属于化学吸附过程。与传统有盐染色结果相比,染色后的阳离子化棉纤维色深增加,染料利用率提高。     

Removal of reactive dyes from wastewater by acrylate polymer beads bearing amino groups: isotherm and kinetic studies

The aim of this study was to prepare a novel resin for the removal of reactive dyes from aqueous media. To prepare the resin, poly(2‐hydroxyethyl methacrylate/ethylene glycol dimethacrylate) beads were grafted with poly(glycidyl methacrylate) by surface‐initiated atom transfer radical polymerisation. Epoxy groups of the grafted polymer were modified with tris(2‐aminoethyl)amine ligand. The modified resin was characterised by swelling studies, FT‐IR and SEM. Three different reactive dyes were selected (CI Reactive Brown 10, CI Reactive Red 120 and CI Reactive Green 5) and used in the removal studies. The effects of pH, temperature, ionic strength and initial dye concentration on the adsorption capacity of the resin were investigated. The adsorption capacity of the resin for Reactive Brown 10, Reactive Red 120 and Reactive Green 5 was 0.029 ± 0.010, 0.032 ± 0.0019 and 0.042 ± 0.0013 mmol/g resin (34.1 ± 1.2, 47.6 ± 2.3 and 69.3 ± 1.7 mg/g resin) respectively. The equilibrium adsorption data were analysed by Langmuir, Dubinin–Radushkevich, Freundlich and Temkin isotherm models. A good fit was found between the Langmuir isotherm and data for the three dyes on resin. The adsorption kinetic data were modelled using pseudo‐first‐order, pseudo‐second‐order and intraparticle diffusion kinetic equations. It was found that the pseudo‐second‐order equation could describe the adsorption kinetics. The results indicated that the modified resin is an attractive alternative for removing reactive dyes from wastewater.     

草酸青霉Penicillium oxalicum菌体吸附活性染料的性能及微观过程

研究了草酸青霉(Penicillium oxalicum)在模拟染料废水中以边生长边吸附的方式对活性翠蓝KN-G, M-GB, K-GL,活性黑K-BR、活性艳蓝M-BR、活性红紫K-3R和活性深蓝K-R 7种水溶性活性染料的脱色性能及吸附过程. 结果显示,生长菌体对7种活性染料具有良好的脱色性能,染料初始浓度为200 mg/L时,平均脱色率可达93.0%;染料初始浓度为400 mg/L时,活性翠蓝KN-G和M-GB的脱色率仍达到了99.7%和99.9%. 上清液的紫外光谱图及染料分子中铜离子浓度的检测结果表明,染料通过吸附方式从废水中去除. 通过SEM, TEM观察发现,生长菌体在吸附过程中,菌丝发生肿胀膨大,细胞壁发生结构重组,厚度增加10~15倍. 细胞壁的结构变化是生长菌体吸附染料的重要机制,为染料吸附提供位点和进入细胞内部的通道.     

Electrochemical degradation of three reactive dyes using carbon paper cathode modified with carbon nanotubes and their simultaneous determination by partial least square method

We investigated the treatment of a mixture of three reactive textile dyes (C. I. Reactive Red 195, C. I. Reactive Yellow 84 and C. I. Reactive Blue 69) by electro-Fenton (EF) process using carbon paper cathode modified with carbon nanotubes (CNTs). To study the degradation of mixture of three dyes, a rapid analytical methodology based on recording UV-Vis spectra during the EF process and the data treatment using partial least square (PLS) as a multivariate calibration method was developed. The three reactive dyes were quantified simultaneously despite the overlap of their spectra. Central composite design was used in the modeling and optimization of the electrochemical decolorization process. The independent variables for modeling were initial concentration of three dyes, applied current in the electrolysis system, and reaction time. Results indicated that the optimum applied current value was about 400mA for the EF process. Analysis of variance (ANOVA) showed that predicted responses by CCD match the experimental values logically with the amount of R2 more than 0.92.     

Adsorption Behavior of Basic Dyes on Activated Clay

Abstract

Activated clay was used to study the adsorption behavior of dyestuffs in synthetic wastewater containing dyestuffs. Three basic dyes were used: C.I. Basic Red 18 (or BR18), C.I. Basic Red 46 (BR46), and C.I. Basic Yellow 28 (BY28). Adsorption occurred almost instantaneously upon contact. The mechanism of adsorption was explained by a charge to the electrostatic attractive force described in the Langmuir adsorption isotherm. The mass transfer coefficient was also calculated by the external mass transfer model in an adsorbent according to Mckay et al. Parameters including species of basic dyes, initial concentration, temperature, size of adsorbent, and NaCl were extensively investigated.     

Strongly basic anion exchanger Lewatit MonoPlus SR-7 for acid,reactive, and direct dyes removal from wastewaters

The strongly basic anion exchanger Lewatit MonoPlus SR-7 (SR-7) of polystyrene matrix was applied for removal of the textile dyes such as C.I. Acid Orange 7 (AO7), C.I. Reactive Black 5 (RB5), and C.I. Direct Blue 71 (DB71). The dyes sorption on SR-7 was examined based on the initial dye concentration, phase contact time, type of additives and their concentrations, and solution pH. The equilibrium and kinetic characteristics of the dyes uptake by SR-7 followed the Langmuir isotherm model and the pseudo-second-order model. The dyes sorption in the column system was also investigated.     

Adsorption of Several Dyes from Aqueous Solutions on Silica-Containing Complex-Oxide Gels

Abstract

Removal of dyes from aqueous solutions was investigated in a batchwise operation using binary or ternary silica-containing complex-oxide gels as adsorbents. The following three combinations of gels showed the best results: (1) silica-titania-magnesia gel for C.I. Acid Blue 40, (2) silica-titania gel for C.I. Basic Blue 3, and (3) silica-titania gel treated with alkali for C.I. Reactive Red 5. The adjustment of the initial pH of the dye solution was effective in all cases. Freundlich-type adsorption isotherms related the amount of dye adsorbed to its equilibrium concentration in solution. The gels which adsorbed the dye abundantly were effectively regenerated for reuse by heating them at 600°C, which caused decomposition of the dye.     

稻草作为生物吸附剂去除水溶液中偶氮染料的研究

用低值易得的稻草作为生物吸附剂对活性红和中性黄两种偶氮染料进行吸附处理研究,考察了吸附剂粒径、初始染料浓度、吸附时间、溶液初始pH等因素对染料吸附的影响。结果显示,吸附剂粒径200目、活性红染料浓度40mg/L、中性黄染料浓度50mg/L、吸附时间20min、吸附物剂量5g/L、初始pH2时,碎稻草对两种偶氮染料的吸附效果显著,分别达到活性红84%、中性黄94%。     

Diffusion mechanism of direct dyes into a cellulose membrane: The structural effect of direct dyes on the adsorption rate

The transport of three typical direct dyes, C.I. Direct Yellow 12, C.I. Direct Red 2, and C. I. Direct Blue 15, into a cellulose membrane has been studied at 55°C. Sodium chloride was used as a stimulator for dyeing. The effects of the concentration of the stimulator on the adsorption isotherms, the adsorption rate, and the concentration profiles in the membrane were tested. The experimental adsorption rates of three dyes were quite different. The diffusion mechanism of the dyes into a cellulose membrane was analyzed on the basis of the parallel transport equation of surface and pore diffusion as developed in our previous paper. The experimental uptake curves showed good agreement with the theoretical curves for surface diffusion control. Experimental concentration profiles also agreed reasonably well with the theoretical lines for surface diffusion control rather than pore diffusion control. The surface diffusivities of three dyes were quite different and nearly independent of the adsorbed phase concentration of the dye.