BIOSORPTION STUDIES ON NACL-MODIFIED CERATOPHYLLUM DEMERSUM: REMOVAL OF TOXIC CHROMIUM FROM AQUEOUS SOLUTION

The present research provides information on the Cr(VI) removal potential of NaCl-modified Ceratophyllum demersum, an aquatic plant biomass. The effects of various parameters including pH, biomass dosage, contact time, and initial concentration on Cr(VI) biosorption were investigated. The best conditions for Cr(VI) biosorption in the present study were: pH of 2, biosorbent dose of 8 g/L, and contact time of 60 min. Under these conditions, maximum adsorption capacity of modified C. demersum for Cr(VI) was 10.20 mg/g. The experimental biosorption data were modeled by Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The biosorption process followed the Langmuir isotherm model with a high coefficient of determination (R² > 0.99). The biosorption process followed pseudo-second-order kinetics. Further, the biosorbent was characterized by Fourier transform-infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The results showed that biosorption of Cr(VI) on NaCl-modified C. demersum occurred through chemical sorption.     

Note EXTRACTION EQUILIBRIUM OF MERCURY(II) FROM AQUEOUS AMMONIUM THIOCYANATE SOLUTION WITH TRIISOBUTYLPHOSPINE SULFIDE

The extraction equilibrium of mercury(II) from aqueous ammonium thiocyanate solution with triisobutyl-phosphine sulfide(=TIBPS=S¯) in toluene has been measured at 303 K. It was found that mercury(II) is extracted according to a solvation reaction by TIBPS as a mercurydl) :TIBPS 1:2 complex, Hg(SCN)₂S2, as follows:

The extraction equilibrium constant, K_e, was evaluated as K_e = 1.8 × 10⁶ (dm³/mol)².     

实验条件对减压膜蒸馏法脱除水溶液中MIBK的影响

本文采用平板式减压膜蒸馏技术对水溶液中MIBK的脱除进行了研究,分别考察了料液温度、料液流量及减压侧压力对MIBK的脱除及效率的影响。     

利用低浓度表面活性剂胶团强化超滤处理含锌废水

利用低浓度的阴离子表面活性剂十二烷基硫酸钠（SDS）,对含Zn^2＋废水进行了胶团强化超滤（MEUF）研究．结果表明：进料液的静置时间为3h时,Zn^2＋在SDS胶团上的吸附达到平衡状态。当Zn^2＋的浓度一定时,由于发生在膜表面的浓差极化现象的影响,在进料液中投加浓度低于1倍临界胶束浓度（CMC）的SDS,不但在很大程度上降低了SDS的用量,而且亦可获得较高的Zn^2＋截留率和渗透通量,Zn^2＋的截留率主要受膜表面SDS浓度的影响。随着进料液中SDS浓度的升高,渗透通量逐渐降低,而渗透液中SDS的浓度随之不断增大,但无论进料液中SDS浓度有多大,渗透液中SDS的浓度都不会高于1倍CMC（2．25g／L）,所以渗透液中的SDS的损失相对较小。Zn^2＋截留率随进料液中Zn^2＋浓度逐步增大而逐渐减小,基于低浓度表面活性剂的胶团强化超滤技术适宜处理低浓度含Zn^2＋废水．     

用生物活性炭纤维新技术去除水中有机污染物

研制了生物活性炭纤维，用于去除水中有机污染物。采用循环流动法把微生物固定在活性炭纤维上，并用扫描电镜观察微生物在炭表面的生长情况。测试了生物活性炭纤维去除微污染源水中有机物的性能，并通过GC—MS图谱分析了处理前后水中有机物的变化。经处理后，水中的CODMn降到了2．5mg／L(饮用水的标准)以下，UV254的平均去除率高达94％，处理容量达到2880mL／g。另外，在相同的实验条件下，将生物活性炭与活性炭纤维的吸附性能作了对比，结果表明以ACF作为载体的生物活性炭纤维(BACF)技术在处理容量和处理效果上均显著优于其它两种处理方法，显示了此项新技术在水的深度处理领域的巨大应用潜力。     

REMOVAL OF TOLUENE AND DICHLOROMETHANE FROM AQUEOUS PHASE BY GRANULAR ACTIVATED CARBON (GAC)

Chlorinated hydrocarbons and aromatics constitute the major class of volatile organic compounds that contaminate groundwater. In this study, the equilibrium uptake and column dynamics for the adsorption of dichloromethane (as a typical chlorinated hydrocarbon) and toluene (as a representative of aromatic compounds) from aqueous phase on coal-based granular activated carbon (GAC) were investigated. The adsorption isotherms were measured in a temperature range of 20–40°C. The experimental data obtained were correlated with several adsorption isotherm models. The Langmuir model was well adapted to describe the dichloromethane adsorption on GAC, while the adsorption of toluene on GAC was found to be well described by the Langmuir-BET hybrid model in the stated temperature range with R-squared value of about 0.99. The variations in adsorption breakthrough curves of toluene and dichloromethane with respect to operational parameters such as initial concentration, flow rate, column length, and temperature were investigated. The experimental breakthrough curves of both adsorbates are well fitted by Yan's model with high accuracy (R-squared value of 0.98–99) in most cases.     

胶束强化超滤脱除氯苯及其膜污染的研究

以十六烷基氯化吡啶 (CPC)作为表面活性剂 ,利用聚醚酰亚胺 (PEI)中空纤维超滤膜 ,对含氯苯废水进行了胶束强化超滤 (MEUF)研究 ,讨论了 CPC浓度对氯苯脱除的影响 ,以及料液流速、操作压力和操作时间对膜污染的影响。在 CPC浓度 (Cf)为 3 .1 g/L～ 1 8.6 g/L的范围内 ,氯苯浓度为 0 .45 g/L时 ,CPC的截留率可大于 95 % ,而氯苯的脱除率可达 98.0 %以上 ,渗透通量可达 1 .0× 1 0 -10 m3/m2·s·Pa。采用去离子水对膜清洗 1 h后 ,膜纯水通量恢复率可达 95 %。     

EXTRACTION OF NICKEL FROM AQUEOUS SULFATE SOLUTION INTO BIS(2,2,4-TRIMETHYLPENTYL)PHOSPHINIC ACID,CYANEX 272TM -EQUILIBRIUM AND KINETIC STUDIES

ABSTRACT

Equilibrium and kinetic studies have been carried out on the extraction of nickel from sulfate solutions using bis(2,2,4 trimethylpentyl) phosphinic acid HDTMPP, “Cyanex 272tm”- It was found that nickel extraction in HDTMPP was favored by the presence of sodium in the organic phase and that equilibrium nickel concentration could be written in terms of the pre-equilibrated extractant concentration

Kinetic studies were carried out using the rising drop method, reaction orders were determined with respect to the aqueous phase nickel concentration, Ni²⁺, the aqueous phase sodium concentration, Na ⁺ the pH, the organic phase dimer concentration ------ and the organic phase sodium salt concentration ---- In addition, it was found that the extraction kinetics could be explained in terms of an aqueous phase interfacial reaction accompanied by diffusion through the interface. Mass transfer coefficient values were determined indicating extraction rates for metal extraction into HDTMPP were the same order of magnitude as those found for HDEHP.     

有色高强丙纶长丝生产与技术探讨

论述了在国产二步法［１］生产装置上纺制有色高强丙纶长丝的生产技术特点,初步探讨了影响有色纤维强度的因素及色差现象的产生     

碳纤维/聚碳酸酯复合材料研究

本文制备了碳纤维增强聚碳酸酯(PC)复合材料并研究了其性能,相比玻璃纤维增强PC,碳纤维增强PC在机械性能、电性能和加工性等方面有明显的提高.随着碳纤维含量的增加,拉伸强度、弯曲强度、弯曲模量明显呈上升趋势.而伸长率和冲击强度在碳纤维含量为6%时达最大值,分别为10.4%kJ/m~2和8.7kJ/m~2.加工流动性有了明显的提高,且随碳纤维含量的增加而逐渐降低.碳纤维的加入,也改善了PC的导电性,当碳纤维含量为10%时,导电电阻率已达到9.0×10~6Ω/sq.     

EQUILIBRIUM OF CO2 IN AQUEOUS DIETHANOLAMINE(DEA) AND AMINO METHYL PROPANOL (AMP) SOLUTIONS

Equilibrium data of CO₂ in aqueous solutions of DEA and AMP for a range of CO₂ partial pressure (0.5-100 k Pa) and temperature (25-80^°C) obtained using a stirred cell reactor is presented in this paper. The data were analyzed using the Deshmukh and Mather Model. It has been found that this model is able to predict results which are close to the experimental data in terms of the total CO₂ loadings and the pH of the solution, an additional parameter which was monitored in this work. Comparison was also made with other published results using the different interaction parameters generated in this work. Good agreement between predicted and experimental values were also observed.     

铜（II）/明胶（酶解明胶）络合物的制备及其络合形态的探讨

许多金属元素对于生物体是必需的,Ｎａ、Ｋ、Ｍｇ、Ｃａ、Ｍｎ、Ｆｅ、Ｃｏ、Ｃｕ、Ｍｏ和Ｚｎ在人体中的含量约３％;各种金属离子在生物体中具有不同的作用,其功能是很复杂的．铜在生物体内主要是进行氧化还原反应,起输送氧气和电子载体的作用．如果人体内缺乏铜,则...     

超级电容器用活性炭纤维的研制(Ⅰ活性炭纤维的强度与比表面积)

分别以粘胶纤维和粘胶炭纤维为原料，经镍盐溶液浸渍后制备活性炭纤维。比较两种原料制得的活性炭纤维的强度和比表面积；考察它们随镍盐溶液浓度、活化温度和活化时间的变化情况。结果表明，两种原料制得活性炭纤维的强度和比表面积随上述三因素各自的变化趋势一致；并由此初步确定了比表面积～1200m^2／g,强度～0．3GPa的粘胶基活性炭纤维的制备工艺.     

柚子皮吸附活性艳蓝KN-R和活性艳橙X-GN性能研究

采用间歇实验,考察了初始pH、柚子皮投加量、柚子皮粒径、离子强度、染料初始含量及接触时间对柚子皮去除废水中的活性艳蓝KN-R及活性艳橙X-GN这2种染料影响。结果表明,酸性pH条件下吸附效果良好,柚子皮能有效地去除废水中的KN-R和X-GN,对KN-R和X-GN的去除率达到97.48%和95.63%;柚子皮粒径变化对吸附效果影响不明显,吸附时间宜控制在480 min以上。柚子皮可作为一种新型吸附剂应用于活性染料废水的处理,作为一种农业废物的资源化加以利用。     

KINETIC STUDY OF SYNTHESIZING DIALKOXYMETHANE USING 4-(TRIALKYLAMMONIUM) PROPANSULTANS AS NEW PHASE-TRANSFER CATALYSTS

In this work, sulfobetaine (4-(trialkylammonium) propansultan (TAAPS)) was first developed as a new phase-transfer catalyst for synthesizing dialkoxymethane. The addition reaction of 1,3-propane sultone (PS) and trialkylamines (TAA) was successfully carried out to synthesize sulfobetaines in a homogeneous organic solution. In this work, for the first time, five different TAAPSs, which possess high reactivity, stability, selectivity, and performance, were employed as phase-transfer catalysis to synthesize dialkoxymethane. The reaction of alcohol and dibromomethane in a highly alkaline solution of KOH/organic solvent two-phase medium to produce dialkoxymethane was carried out under phase-transfer catalysis using 4-(trialkylammonium) propansultan as the catalyst. From the experimental observation, a rational reaction mechanism using this new phase-transfer catalyst was proposed. Kinetics of the reaction are studied in detail.     

连续催化湿式过氧化处理腈纶废水研究

以金属Mn和Ce的硝酸盐为活性组分的前驱物,以介孔分子筛SBA-15为载体,浸渍焙烧法制备了负载型催化剂MnOx/SBA-15、CeOx/SBA-15及MnOx-CeOx/SBA-15,并以H2O2为氧化剂,在温和条件下连续催化湿式过氧化(CWPO)处理腈纶废水。结果表明,MnOx-CeOx/SBA-15催化剂表现出较好的催化活性和稳定性。试验选择了连续流固定床反应装置,考察了反应温度、进料流量、催化剂投加量、H2O2投加量等因素对COD去除率的影响。由试验得出,在150℃,进料流量25 mL/min,催化剂投加30 g/L,H2O2投加5%时,腈纶废水的COD去除率达到80%左右。     

VOLATILE ORGANIC COMPOUND (VOC) REMOVAL BY ADSORPTION ONTO ACTIVATED CARBON FIBER CLOTH AND ELECTROTHERMAL DESORPTION: AN INDUSTRIAL APPLICATION

Previous studies have shown good adsorption of volatile organic compounds (VOC) present in air onto activated carbon fiber cloths (ACFCs). In a chemical plant, a treatment process was carried out to control a gaseous emission (flow close to 100 m³ h^-1) loaded with methylene chloride at concentrations ranging between 3 and 30 g m^-3. A final mass flow lower than 100 g h^-1 was required in the outlet emission. Two identical cylindrical ACFC modules worked alternately in an adsorption-desorption cycle. The outlet pollutant mass flow was found to be less than 4 g h^-1. After saturation of the adsorbent, the module was electrothermally regenerated. Desorbed methylene chloride was recovered in a cryogenic trap and reused in the chemical processes of the plant. This system worked continuously for more than 18 months (24 h per day) with no operating problems and giving good performance in terms of VOC outlet emission concentrations.     

粘度和光谱方法研究二元阴离子型丙烯酰胺共聚物（P3A）在不？…

采用粘度和光谱方法 ,研究了强酸性和弱酸性 2种阴离子型单体与丙烯酰胺的三元共聚物(P3A)在稀水溶液中 pH诱发的构象变化 ,P3A聚合物由丙烯酰胺 (AM)和强酸性离子单体 (AMPS)及弱酸性离子单体 (AA)组成 .试验结果表明P3A聚合物溶液的粘度随pH呈现非单调的增长关系 ,在 pH为 4～ 5范围内产生急剧的升高 ,这现象归因于聚合物链团从紧密状态向膨胀状态迅速的转变 .这两种状态的溶液粘度变化幅度和聚合物P3A中AMPS和AA组合比例紧密相关 ,芘探针在聚合物P3A溶液中的荧光强度和 pH的关系呈现类似粘度变化的结果 .在低pH值时 ,发现单一弱酸离子共聚物 (P2AA)溶液发生相分离 ,然而在含有强酸单元 (AMPS)的P3A聚合物情况下 ,这种现象不再产生 .     

新型硅烷偶联剂对石英纤维/含硅芳炔复合材料界面增强增韧改性

采用一种自主设计制备的含有端炔、醚键和酰亚胺环的硅烷偶联剂(AAS),对石英纤维/含硅芳炔复合材料进行增强、增韧改性。采用DSC、FT-IR以及TGA分析表征了AAS参与PSA的交联固化,与PSA形成良好的化学作用;XPS测试表明AAS与QF产生化学键合;SEM分析表明,AAS的使用改善了QF与PSA的粘结性能,提高了界面结合强度,常温条件下,复合材料的层间剪切强度(ILSS)和弯曲强度相比于未改性的分别提高了50.6%和43.0%,在250℃时,ILSS、弯曲强度的保留率分别为66.0%和84.2%。经过AAS改性后,复合材料的耐冲击性能也得到了提高,常温下QF/PSA的冲击强度较未改性时提升了20.4%。     

以硝酸铝为原料制备铝溶胶的研究

以廉价的无机盐为原料,采用溶胶-凝胶法制备了性能良好的铝溶胶,采用X射线衍射分析(XRD)和差热热重分析(TG-DTA)现代测试技术对干燥后的凝胶进行物相分析和热稳定性分析。实验发现,采用沉淀后立即过滤的方法能够提高去除NO-3离子的效率,缩短制备周期。无定形沉淀在较高的pH条件下,能促使溶解-重结晶反应发生,生成勃姆石颗粒,颗粒的结晶度随着老化时间的延长而有所提高。