胶原多肽基表面活性剂对染料废水的泡沫分离性能

以结晶紫溶液模拟染料废水,研究了胶原多肽基表面活性剂(CBS)对染料废水的泡沫分离性能。通过单因素实验考察了pH、气速、表面活性剂质量浓度、泡沫相与液相高度比(H_F/H_L)、染料初始浓度、乙醇添加量等因素对废水中染料分离的影响。结果表明,CBS适用于碱性条件下染料废水的泡沫分离;随着气速的升高,染料的去除率增加,但富集比降低;随着CBS用量的增加,染料的去除率先增加而后降低,富集比随CBS用量的增加而降低;当泡沫相高度与液相高度比为3左右时,染料去除率较高;添加适量的乙醇对泡沫分离是有利的;在较佳的分离条件下,染料的去除率可达80%,富集比达到16。上述研究结果表明,胶原多肽基表面活性剂可用于染料废水的泡沫分离。     

Preparation of Modified Reduced Graphene Oxide nanosheet with Cationic Surfactant and its Dye Adsorption Ability from Colored Wastewater

In this paper, reduced graphene oxide (rGO) nanosheet from graphite was synthesized using the top-down approach. The surface of rGO was modified by cetyltrimethylammonium bromide (CTAB) to prepare rGO/CTAB adsorbent for anionic dye removal. The prepared rGO/CTAB was characterized by XRD, FTIR, FE-SEM and TGA. The operation parameters (surfactant concentration, adsorbent dosage, pH and initial concentration of dye solution) affecting the batch adsorption process to remove direct red 80 (DR80) and direct red 23 (DR23) were studied in detail. The dye adsorption capacity of rGO/CTAB was 213 and 79 mg/g for DR80 and DR23, respectively. In addition, dye removal followed the Langmuir isotherm with pseudo-second order reaction kinetics.     

Study on Riboflavin Recovery from Wastewater by a Batch Foam Separation Process

Abstract

A batch recovery of riboflavin via foam separation from industrial simulative wastewater was studied using a cationic surfactant, cetyltrimethyl ammonium bromide (CTAB). The experimental parameters examined were the surfactant concentration, air flow rate, pH, and foam height. Under optimal operating conditions obtained through an orthogonal experiment, the maximum enrichment ratio of 48.7 was achieved for riboflavin along with 99.3% removal efficiency. The optimal operating conditions had the concentration of CTAB at 0.3 g/L, air flow rate at 400 ml/min, foam height at 90 cm, and pH at 12. Therefore foam separation proved to be an effective method to recover the riboflavin in terms of the good enrichment and removal efficiency.     

泡沫分离法处理甲基橙染料废水工艺

为开发一种设备和工艺简单、成本低且不产生二次污染的染料废水处理方法,以甲基橙模拟染料废水为研究体系,对泡沫分离法脱除甲基橙染料废水色素的工艺进行了研究。研究了pH值、气体流速、表面活性剂质量浓度、装液量对脱色的影响,以表面活性剂十六烷基三甲基溴化铵(CTAB)为捕收剂,确定的最佳操作条件为:pH值6.0,气速0.04 m3/h,CTAB质量浓度90 mg/L,装液量1 000 mL,第1次脱色富集比β为111.0,脱色率R为99.5%。然后,对破沫液进行过滤,所得的滤液可代替部分表面活性剂进行下一次脱色。当补加的表面活性剂与废水中甲基橙的摩尔比为0.89∶1时,第2次脱色率为99.4%,富集比为50。     

泡沫分离法提取乙醇水体系中甲基橙

采用泡沫分离法对含甲基橙的乙醇水溶液进行了提取研究. 考察了乙醇体积分数、气体流量、pH、甲基橙浓度和表面活性剂浓度对提取效果的影响,并对泡沫分离乙醇-水体系中提取中药有效成分的可行性进行了探讨. 结果表明,以十六烷基三甲基溴化铵(CTAB)为表面活性剂,在乙醇体积分数25%的乙醇-水体系中,在pH 6.0、气速80 mL/min、甲基橙浓度35 mg/L及CTAB浓度80 mg/L的操作条件下,甲基橙的富集比为14.38,回收率在98.5%以上. 在一定范围内提高表面活性剂浓度或加入稳泡剂以削弱乙醇的消泡作用,从而将泡沫分离技术应用于乙醇-水体系中中药有效成分的提取是可能的.     

染料废水中添加剂对角蛋白助剂脱色性能影响研究

研究了染料废水中电解质和表面活性剂对角蛋白助剂脱色性能的影响,结果表明：①电解质的加入,对角蛋白助剂的脱色效果影响微弱,对酸性湖蓝A模拟废水基本无影响;②表面活性剂存在时,对角蛋白助剂的脱色效果影响非常大,当非离子表面活性剂的量〉5 g/L时,活性黄棕KGR模拟废水的脱色率基本稳定在70%左右,但酸性湖蓝A模拟废水脱色率仅为15%左右;当阴离子表面活性剂和两性表面活性剂加入后,脱色率几乎为0。     

Chromate removal from wastewater using micellar enhanced crossflow filtration: Effect of transmembrane pressure and crossflow velocity

Removal of chromate from wastewater was investigated using Micellar Enhanced Crossflow Microfiltration Technique (MEMF) with cationic surfactant, cetyltrimetylammoniumbromide (CTAB). The variation of chromate, surfactant rejections and permeate flux with time were measured at two different CTAB concentrations as a function of transmembrane pressure drop (ΔP) and crossflow velocity, while CTAB/chromate, membrane pore size, temperature and pH of the feed solution was kept constant. For low CTAB concentration, it was observed that the efficiencies of chromate and surfactant removal increased with increasing ΔP, but decreased with increasing crossflow velocities. It was also observed that the effects of crossflow velocities and ΔPs on the rejections decreased for high CTAB concentration. It was found that fouling of the membrane by surfactant is very rapid at low crossflow velocity and high ΔPs at low CTAB concentration. As a result of this case, both transient permeate flux (J) and steady state permeate flux (J^?) decreased with decreasing crossflow velocity and increasing ΔP for both CTAB concentration. Unlike, modified fouling index (MFI) values increase with decreasing crossflow velocity and increasing ΔP. It was also observed that the effect of surfactant concentration in the 150, 200, and 250 kPa pressure and 3, 4, and 5 m/s crossflow velocity intervals dominates at high surfactant concentration.     

铁炭微电解法预处理羧甲基纤维素生产废水

采用铁炭微电解法对羧甲基纤维素废水进行预处理试验,研究了初始pH值、曝气、停留时间等关键因素对COD去除的影响。结果表明当进水COD的质量浓度为16000mg/L,进水初始pH值为3.5,停留时间75min,铁炭体积比为1∶1,曝气量为5L/min,此条件下COD去除率为35.14%,试验达到了预期目的。     

Ce/SBA-15联合Oxone去除水中染料RhB的试验研究

将负载型的Ce/SBA-15与过硫酸氢钾复合盐(Oxone)联合,考察了该联合体系对染料罗丹明B(RhB)的去除效果。结果表明:该体系中RhB的去除符合准一级动力学方程,提高Ce/SBA-15和Oxone投加量,降低初始RhB浓度和提高反应温度会增强RhB的去除效果,未调节溶液初始pH值时,RhB的去除效果最好。制备的Ce/SBA-15在5次循环使用后仍具有约80%的RhB去除率,RhB的去除机制为表面吸附催化。Ce/SBA-15与Oxone联合产生以硫酸根自由基为主的处理技术对难降解污染物质具有潜在的实际应用价值。     

纳米二氧化钛光催化剂处理印染废水的中试研究

依据纳米二氧化钛制备及应用的小试试验基础上确定的工艺路线和条件,设计了处理量为1t/d的中试装置,在该装置上,以难降解偶氮染料4BS为污染物配制的废水进行模拟试验.考察了初始pH、初始浓度、光照强度、催化剂循环使用次数对降解效果的影响.研究表明,该工艺能够有效地将染料褪色、降解,色度去除率达到95%以上,CODCr去除率可达80%以上.     

NaClO-PMS及NaClO-O3协同活化降解印染废水

将次氯酸钠(NaClO)分别与过硫酸氢钾(KHSO_5,简称PMS)和臭氧(O_3)协同活化,用于处理模拟印染废水,以罗丹明B(Rhodamine B,RhB)、活性艳蓝(Reactive Brilliant Blue,Knr)、活性艳红(Reactive Red X-3B)、甲基橙(Methyl Orange,MO)染料的降解率为指标,采用紫外-可见吸收光谱分析测试法,探讨其物质的量比、pH及废水中Cl~-、NO_3~-、SO_4~(2-)、HCO_3~-等因素的影响。结果表明:NaClO-PMS及NaClO-O_3体系最佳物质的量比分别为n(NaClO):n(PMS)=1:1,n(NaClO):n(O_3)=2:3,分别在pH为3～11、3～9时对模拟印染废水具有较好的降解效果,NaClO-PMS体系在酸性条件下降解RhB效果较好,pH=3时降解率可达到96.18%;NaClO-O_3体系在中性条件下对RhB的降解效果较好,pH=7时降解率为97.91%;阴离子对NaClO-PMS及NaClO-O_3体系处理印染废水的影响均较小。     

Comparison study of dyestuff wastewater treatment by the coupled photocatalytic oxidation and biofilm process

Degradation of Rhodamine B (RhB) and COD by means of the coupled photocatalytic oxidation (PCO) and biofilm systems has been studied. The coupled PCO-biofilm systems were divided into two operation systems. The one (R1) consisted of a pre-PCO and a post-biofilm reactor system and the other (R2) was a pre-biofilm and a post-PCO reactor system. In a batch experiment, the order of initial decolorization rate was photocatalytic oxidation > adsorption > photolysis. The color removal rate of RhB was decreased with an increase of the initial COD concentration. In a continuous experimental study, almost all color was removed in the PCO reactor. During 180 days, the color and COD removal efficiencies in the R2 (pre-biofilm + post-PCO) system were higher than those in the R1 (pre-PCO + post-biofilm) system. In our experimental ranges, the PCO process was superior to Fenton oxidation in the color and COD removal.     

电絮凝法处理含锰废水试验研究

采用周期换向电絮凝法处理含锰废水,考察了初始pH值、电流密度、初始浓度等因素对处理效果的影响.结果表明,当初始pH值为9.0,总锰初始质量浓度为40 mg/L,处理时间为5 min,电流密度为23.81 A/m2,电极换向周期为15 min时,总锰的去除率超过98％.电絮凝出水经曝气、絮凝和过滤处理后满足GB18918-2002《城镇污水处理厂污染物排放标准》的要求.     

焦化废水中挥发酚光催化降解去除影响因素的研究

笔者以紫外光为光源,对焦化废水中挥发酚进行了光催化降解去除的实验研究,系统研究了催化剂用量、焦化废水pH值、温度、搅拌强度等因素对去除焦化废水中挥发酚的影响。结果表明,随着催化剂用量和pH值的增加,挥发酚的去除率先提高后降低;挥发酚的去除率首先随着温度和搅拌强度的增加而提高,当达到一定值后基本不再变化。光催化去除挥发酚过程符合一级动力学反应规律。并且随着挥发酚初始浓度的增加,表观速率常数降低。向废水中曝气可提高挥发酚去除率,但曝气量存在最佳范围。     

改性粉末活性炭活化过硫酸盐降解罗丹明B废水

以Co Fe2O4改性粉末活性炭(Co Fe2O4/PAC)作催化剂,过硫酸钾为氧化剂,对模拟罗丹明B(Rh B)废水进行降解,考察各重要因素对降解率的影响。由结果可知,废水原始p H下,催化剂投加质量浓度为0.2 g/L,n(K2S2O8)∶n(Rh B)为20∶1,温度为35~65℃,时间为150 min,20 mg/L的50 m L Rh B溶液可完全降解。改性粉末活性炭使用4次后,仍具有较高催化活性。     

曝气/铁炭微电解预处理制膜废水试验研究

以浙江某制膜公司的生产废水为研究对象,采用曝气微电解对含DMF、DMAC等强有机溶剂的制膜废水进行预处理.结果表明,曝气微电解最佳pH为2～3,最佳停留时间为120 min,其COD去除率较普通微电解工艺至少提高5%.串联曝气微电解反应器处理中COD去除率存在二次跃迁曲线.历时30 d的稳定运行结果表明,当进水COD为10 000～20 000 mg/L时,COD去除率达52%以上,可以使原水B/C由0.22提高到0.45以上.     

超声波-Fenton法协同降解含表面活性剂SDS弱酸艳红染料废水的研究

采用Fenton氧化、超声辐射和超声-Fenton氧化三种方法处理含阴离子表面活性剂SDS的弱酸艳红B染料废水,考察溶液初始pH、H2O2投加量、FeSO4投加量、反应时间和超声功率对废水色度和COD的影响。结果表明:单独超声对废水色度和COD的去除没有效果,超声-Fenton氧化法对废水COD的去除效果明显优于Fenton氧化法。在pH 2.5,温度50℃,H2O2投加量4 mL/L,FeSO4投加量300 mg/L,反应时间90 min及超声功率400 W的条件下,废水色度去除率为98%,COD去除率为72%,比单独Fenton氧化法COD去除率提高25%。     

A semi-conducting polypyrrole/coffee grounds waste composite for rhodamine B dye adsorption

A composite based on coffee grounds waste (CGW) coated with the semi-conducting polypyrrole (PPy) was prepared by pyrrole polymerization using potassium persulfate as oxidant. The composite was characterized by FTIR spectroscopy, cyclic voltammetry, UV/vis spectroscopy, scanning electron microscopy (SEM) and TGA analysis. SEM analysis showed homogeneous coating of coffee fibers with spherical nanoparticles of PPy with diameters in the range of 200–300 nm. Aqueous adsorption experiments of rhodamine B dye (RhB) onto the as-prepared composite were performed. The effect of pH and initial dye concentration (C₀) on the adsorption behavior was studied. The results showed that this material was an efficient adsorbent of RhB dye at alkaline pH. The adsorption experiments were set at C₀ = 200 mg/L and initial pH values of 2.0, 3.25 and 9.0, the adsorption capacities were 7.22, 13.8, and 19.0 mg of dye/g of the composite, respectively. Nonetheless, when pH was maintained at 9.0 throughout adsorption time, the adsorption capacity increased to 32 mg of dye/g of the composite. When performing adsorption tests using pure CGW, dye adsorption was insignificant at any pH level. Adsorption isotherm for RhB at controlled pH of 9.0 was well described by the Redlich–Peterson model and by the typical Langmuir adsorption model with a theoretical maximum adsorption capacity (q_max) of 50.59 mg of dye/g of composite.     

电絮凝气浮法处理分散艳蓝E-4R废水的研究

采用电絮凝气浮法处理分散艳蓝E-4R染料废水,考察了电解时间、废水初始浓度、pH值及外加电解质氯化钠和絮凝剂等不同反应条件对废水处理效果的影响。结果表明,染料废水脱色率随着电解时间的加大而逐渐增大并随初始浓度的增大而慢慢降低;pH值在2.5~10范围内电解均可获得较高的脱色率。初始浓度为400 mg/L的染料废水,电解20 min后脱色率即达87.39%,但TOC去除率只有10.49%。投加50 mg/L氯化钠后,脱色率和TOC去除率分别达到93.61%和73.49%,TOC去除率提高60%以上。在电解的条件下投加不同絮凝剂能提高染料废水的处理效果,其处理效果从大到小依次为:硫酸铝>三氯化铝>硫酸亚铁,它们的适宜用量分别为50,100,100 mg/L。     

响应曲面法优化电化学耦合体系预处理焦化废水

针对焦化废水有机负荷高、生物抑制性强等特点,采用电化学耦合体系进行预处理研究。以原厂污泥制备污泥活性炭（AC）粒子电极,并表征其表面含有羟基、醚基、羰基、羧基等多种含氧官能团,有利于催化反应。考察阴极曝气对预处理的影响及降解机理分析,结果表明曝气有利于开环反应。基于Central-Composite响应曲面法考察外加电压、初始pH、曝气量、AC填充比等因素对预处理的单独影响及交互作用,并以COD去除率为评价指标。结果表明：各因子的影响显著性顺序为AC填充比 > 初始pH > 曝气量 > 外加电压,其中初始pH和曝气量的交互作用较显著。最佳运行条件为外加电压15 V,初始pH 5.8,曝气量12.4 ml·min^-1,AC填充比50%,反应时间45 min,此时COD去除率达46.8%。废水COD由4700 mg·L^-1降至2500 mg·L^-1,色度去除率为50%,B/C由0.05增至0.37,可生化性明显提高,且能耗较低为0.971 kW·h·（kg COD）^-1。研究表明,采用电化学技术能有效预处理焦化废水,并提高可生化性。