H2O2—Fe^2＋氧化法处理对氨基酚工业废水的研究

结果表明,利用Ｈ２Ｏ２－Ｆｅ２＋ 氧化法处理对氨基酚（ＰＡＰ）工业废水是切实可行的。当ＰＡＰ质量浓度在１．６ｇ／Ｌ～２．０ｇ／Ｌ范围内,在Ｈ２Ｏ２／ＰＡＰ＝ ４．０（质量比）,ＦｅＳＯ４·７Ｈ２Ｏ质量浓度为１．０ｇ／Ｌ条件下,反应１ｈ 后,工业废水中对氨基酚的去除率达９８％ ～９９％ 。降低了废水的色度并提高了废水的可生化性,该方法对反应条件（如温度和ｐＨ值等）没有严格要求,便于工业应用。     

二烯基双酚A醚接枝低密度聚乙烯的制备

介绍了二烯基双酚Ａ醚（ＤＢＡＥ）与低密度聚乙烯（ＬＤＰＥ）在Ｈａａｋｅ转矩流变仪的混炼器中进行熔融接枝反应,采用红外光谱（ＦＴ－ＩＲ）分析证实了接枝共聚物（ＬＤＰＥ－ｇ－ＤＢＡＥ）并通过对ＬＤＰＥ－ｇ－ＤＢＡＥ的接枝率（ＧＲ）和熔体流动速率（ＭＦＲ）测试,考察了制备条件（反应温度,引发剂用量和ＤＢＡＥ用量）对接枝反应及产物的影响,ＬＤＰＥ－ｇ－ＤＢＡＥ的最终目的是作为高密度聚乙烯／聚碳酸酯共混体系     

PP／LDPE共混物熔体流动特性的研究

将两种熔融流动指数（ＭＦＩ）相差大的聚丙烯（ＰＰ）分别与一低密度聚乙烯（ＬＤＰＥ）进行共混，用熔体流动速率仪测定其流动特性。发现ＭＦＩ值高的ＰＰ，当共混比ＰＰ／ＬＤＰＥ为５０／５０时，其熔体流动速率（ＭＦＲ）为最大，本文对此作了初步的分析和讨论。     

生物转化法生产果糖1,6-二磷酸反应条件优化

研究了利用游离酵母细胞转化葡萄糖为果糖１,６－二磷酸（ＦＤＰ）的反应条件。采用甲苯进行细胞透性化处理获得优化效果。合适的反应条件为：温度３５～４０℃、ｐＨ６．０、葡萄糖浓度大于０．１ｍｏｌ／Ｌ和无机磷浓度小于０．２ｍｏｌ／Ｌ。在该条件下,于补料分批式反应中,ＦＤＰ积累浓度达到０．３９９ｍｏｌ／Ｌ（１３５．６５ｇ／Ｌ）,对糖收率达到２８．２％。     

树脂的质量对交换速率的误差分析

ERRORANALSISOFMASSOFRESINTOEXCHANINGRATE1前言离子交换动力学是研究离子交换速率及机理，揭露中间的反应历程及各种反应规律的理论。在稀溶液中，树脂表面液膜的扩散是交换速率的控制步骤。一定量的树脂，当质量由（OS土OOI）g改变到（OI上DOI）g，是否由于树脂质量的改变，当树脂直径不同时，它们的交换速率是否仍然可以定量的比较，交换速率的快慢。从动力学方程：－1／H；；（－P）＝Hq八【K”儿／附。（t／F）＋（l－KDI：／D。）中可知：交换量F与交换速率有关，即：F—Q；／Q。，其中Q；，Q。是在交换过…     

纳米级无机粒子对聚乙烯的增强与增韧

对μｍ级ＣａＣＯ３、ＴｉＯ２和ｎｍ级ＳｉＣ／Ｓｉ３Ｎ４粒子填充ＬＤＰＥ的性能进行了研究。实验证明，μｍ级粒子对ＬＤＰＥ虽无明显的增强增韧作用，但也未使基体的机械性能大幅度下降。ｎｍ级ＳｉＣ／Ｓｉ３Ｎ４对ＬＤＰＥ有较大的增强增韧作用，在５％质量分数时冲击强度出现最大值，缺口冲击强度达５５．７ｋＪ／ｍ２为纯ＬＤＰＥ的２０３％；伸长率到６２５％时仍未断裂，为纯ＬＤＰＥ的５００％，但熔体流动速率急剧下降，仅为纯ＬＤＰＥ的２６％，当含量在３％和１５％质量分数时，熔体流动速率分别为纯ＬＤＰＥ的３３７％和１５１％。     

LDPE悬浮聚合接枝PS及其表征

研究了ＬＤＰＥ悬浮接枝ＰＳ合成ＬＤＰＥ－ｇ－ＰＳ接枝共聚物的工艺，此接枝共聚物可作为某些聚合物共混的相容剂。讨论了苯乙烯溶胀ＬＤＰＥ时间、引发剂浓度和ＬＤＰＥ与苯乙烯投料比对接枝率的影响，发现溶胀时间为４ｈ、反应时间为８ｈ、引发剂浓度为１％时、ＬＤＰＥ与苯乙烯投料比为１∶１时，其接枝共聚物接枝率最大可达３８．５％。并对ＬＤＰＥ－ｇ－ＰＳ接枝共聚物进行了ＤＳＣ、ＩＲ及接枝率测定的表征。     

HDPE/AS共混体系形态及力学性能

研究了相容剂ＬＤＰＦ－ｇ－ＡＳ对ＨＤＰＥ／ＡＳ共混体系形态及力学性能的影响。红外光谱研究表明采用固相接枝有效地形成了苯乙烯和丙烯腈与聚乙烯的 支共聚物,将其作为ＨＤＰＥ／ＡＳ共混体系的相容剂可大大减小分散相的粒子尺寸,显著提高共混体秒的力学性能,说明ＬＤＰＥ－ｇ－ＡＳ是该共混体系的有效相容剂。     

裂解肽－Wang树脂的新试剂

用０．５ｍｏｌ／Ｌ二氯二甲基硅烷（ＤＤｓｉ）－１．５ｍｏｌ／Ｌ苯酚／ＣＤＭ－ＨＯＡｃ（１：１）溶液代替经典的８５％三氟醋酸（ＴＦＡ）／Ｈ２Ｏ溶液对肽－Ｗａｎｇ树脂进行酸解释放游离肽反应。测定了裂解前后树脂上肽的取代度并分析了游离肽产物的氨基酸组成，证明裂解收率及产物纯度与ＴＦＡ法相同。ＤＤＳｉ法的成本仅相当于ＴＦＡ法的４．３％。     

UV/HA与铁盐体系对染料的脱色研究

水溶性染料活性艳红（Ｘ－３Ｂ）在铁盐与腐植酸共存下,光解脱色效果明显,结果表明在ＰＨ＝３,１．０＊１０＾－５ｍｏｌ／ＬＦｅ（Ⅲ）与０．５ｇ／Ｌ腐植酸的条件下,２０ｍｇ／Ｌ活性艳红溶液的脱色率为７１．４％。染料溶的ＰＨ值,Ｆｅ（Ⅲ）,腐植酸的浓度以及当杰溶液的初始浓度均对染料的脱色有影响。     

离子交换树脂吸附TP5的热力学和动力学研究

针对凝胶型阳离子交换树脂对TP5的吸附行为,研究了间歇反应中TP5水溶液的吸附热力学与动力学特性。热力学研究表明,TP5在所用树脂上的吸附平衡数据符合Langmu ir吸附等温方程。在283.15~303.15 K之间,TP5的质量浓度在10 g/L时,离子交换树脂对TP5的吸附过程可分两个阶段,第一阶段受液膜扩散控制,第二阶段主要吸附过程受颗粒扩散的控制。利用TP5在不同条件下的动态吸附性能实验,考察了pH值、温度、溶液初始浓度、搅拌转速等因素的影响。采用两相阻力模型描述了TP5在离子交换介质中的动态吸附性能,通过计算得到了TP5在吸附剂颗粒中的颗粒扩散系数,有助于进一步研究小肽在吸附过程中的传质现象。     

D815树脂吸附钒的性能及动力学研究

实验研究了钒溶液在D815树脂上的吸附行为,并从热力学和动力学两个方面对吸附过程进行了分析.结果表明:在温度为30℃,pH为2.20,五氧化二钒初始浓度为15.0g/L条件下,树脂的饱和吸附容量达到最大值520 mg/g;在钒溶液流速为0.1 mL·min(-1)·g(-1)条件下,吸附经过2h左右达到穿透点,50 h...     

Lead removal from aqueous solutions by 732 cation‐exchange resin

Kinetics and thermodynamics of the removal of Pb²⁺ from an aqueous solution by 732 cation‐exchange resin in hydrogen type (732‐CR) were studied in the temperature range of 298–328 K and Pb²⁺ concentration range of 5–50 mol/m³. The effects of ion exchange temperature and initial lead ion concentration on the time evolution of the experimental concentration for the metal ion were investigated. Ion exchange kinetics of Pb²⁺ onto 732‐CR follow the Nernst‐Planck equation and unreacted‐core model (UCM). The diffusion coefficients of counter ions and the efficient diffusion coefficient of lead ions within the resin were calculated. The results show that the ion exchange process is favoured under the particle diffusion control mechanism. The ion exchange isotherm data agreed closely with the Langmuir isotherm. The maximum monolayer exchange capacity for Pb²⁺ was found to be 484.0 mg/g at 308 K. Thermodynamic studies show that Pb²⁺ onto 732‐CR is spontaneous and exothermic in nature. The ion exchange processes were verified by Energy Disperse Spectroscopy (EDS).     

SQD201树脂对钒的吸附-解吸行为及机理

通过静态吸附-解吸实验研究了SQD201树脂吸附-解吸钒的交换平衡和动力学特性,考察了pH值、温度和溶液浓度对离子交换过程的影响. 结果表明,在298 K、pH=2.0、溶液浓度为0.040 mol/L条件下,SQD201树脂的静态饱和吸附量为573.80 mg/g;钒在SQD201树脂上的吸附是吸热过程,符合Langmuir等温吸附方程. 吸附和解吸过程主要受颗粒扩散控制,吸附过程的表观活化能为20.41 kJ/mol,解吸表观活化能为22.21 J/mol. 吸附机理分析表明,SQD201树脂主要吸附的钒阴离子为H2V10O284-,H2V10O284-与树脂的理论摩尔比为1:4.     

KINETICS OF URANIUM EXTRACTION BY MACROPOROUS BIFUNCTIONAL PHOSPHINIC ACID RESIN

ABSTRACT

The rate of extraction of uranium by macroporous bifunctional phosphinic acid (MPBPA) resin from nitric acid medium has been studied under particle diffusion controlled conditions. The internal diffusion coefficient was found to increase with increase in temperature and decrease with increase in particle size. The activation energies and entropies suggest that the extraction of uranium essentially follows ion exchange mechanism at low concentration of nitric acid while it is through linkage of >P=0 group of the resin at high concentrations.     

Anion exchange of uranium from aqueous sulphuric acid solutions: Diffusion kinetics

The ion exchange kinetics of uranium sorption from acidic sulphate solutions onto weak and strong base resins has been studied. In order to facilitate experimentation and analysis, isotopic redistribution experiments of uranyl sulphate ions (with U-235 as a tracer) under conditions of particle diffusion control have been performed. Also, self-diffusion experiments for sulphate ions (with S-35 as a tracer) and counter diffusion measurements involving uranyl sulphate-sulphate exchange have been performed. The ion exchange of uranium is a slow reaction and appears to be particle diffusion controlled at all solution conditions of practical interest. For a weak base resin (Relite MG-1), the self-diffusion coefficient of uranyl sulphate ions changes with particle size, increasing from 1.49 to 4.88 × 10^?9 cm²/s as the particle diameter is reduced from 0.146 to 0.054 cm. With a strong base resin (Dowex-1×8), the self-diffusion coefficient of uranyl sulphate ions remains reasonably constant with varying particle diameter at a value of 1.76 × 10^?9 cm²/s. Sulphate ion self-diffusion coefficients were also constant with particle size (2.50 × 10^?7 cm²/s) and the counter exchange diffusivity lies between the values for the individual species; a typical value is 1.53 × 10^?8 cm²/s. It is argued that resin matrix structure has a significant effect on uranium kinetics and that a knowledge of the relevant diffusion coefficients will provide a rational basis for the design of ion exchange processes and plant equipment.     

阳离子交换树脂对虫草素的静态吸附动力学研究

研究了732阳离子交换树脂对虫草素的静态吸附行为。首先对阳离子交换树脂吸附虫草素的pH条件进行了优化,随后在最佳pH条件下考察了温度、浓度及树脂粒径对虫草素在阳离子交换树脂上静态交换过程的影响,并用动边界模型描述了虫草素交换过程的动力学。确定虫草素交换行为的速度控制步骤为颗粒扩散,并推算出交换过程的表观活化能为36.66 kJ/mol,反应级数为1.60,表观频率因子为5.49×103m in-1。     

KINETICS OF CADMIUM ION SORPTION ON ION EXCHANGE AND CHELATING RESINS

ABSTRACT

Cadmium sorption from aqueous solutions on sulfonic (C-150) and iminodiacetic (S-930) Purolite macroporous resins was investigated. The influence of operating variables such as initial pH, Cd(H) concentration, time and temperature on the equilibrium parameters was measured. The ion preference and sorption ability of resins, i.e. binding constant (b) and saturation capacity {x_m), derived from sorption isotherm, depend on the functional group structure. The Cd(II) uptake is only particle diffusion controlled. The kinetic parameters, i.e. t_1/2 values for 50 % attainment of equilibrium sorption, rate constant (K¯ ) and diffusion coefficient (D¯) are higher on the sulfonic resin. The “moving boundary” particle diffusion model fits the entire ion sorption process on chelating resin, but only the initial sorption on the sulfonic resin, confirming the difference in chemistry between chelation and ion exchange.     

Ion‐exchange adsorption of calcium ions from water and geothermal water with modified zeolite A

The modified zeolite A was prepared by a two‐step crystallization method to remove scale‐forming cations from water and geothermal water. The adsorption kinetics, mechanism and thermodynamics were studied. The calcium ion adsorption capacity of the modified zeolite A was 129.3 mg/g (1 mg/g = 10^?3 kg/kg) at 298 K. The adsorption rate was fitted well with pseudo‐second‐order rate model. The adsorption process was controlled by film diffusion at the calcium ion concentration less than 250 mg/L (1 mg/L = 10^?3 kg/m³), and it was controlled by intraparticle diffusion at the concentration larger than 250 mg/L. The calculated mass‐transfer coefficient ranged from 2.23 × 10^?5 to 2.80 × 10^?4cm/s (1 cm/s = 10^?2m/s). Dubinin–Astakhov isotherm model could appropriately describe the adsorption thermodynamic properties when combined with Langmuir model. The adsorption process included not only ion exchange but also complexation between calcium and hydroxyl ions. The adsorption was spontaneous and endothermal. The high adsorption capacity indicates that the modified zeolite A is a suitable adsorption material for scale removal from aqueous solution. © 2014 American Institute of Chemical Engineers AIChE J, 61: 640–654, 2015     

Kinetic behaviour of boron selective resins for boron removal using seeded microfiltration system

In this study, boron selective ion exchange resins (Dowex-XUS 43594.00 and Purolite S 108) and model boron solutions at different ionic strengths were used in order to perform continuous kinetic studies in a seeded microfiltration stirred cell provided by Micropore Technologies (UK). Mass transfer modelling based on a well stirred system, including maximum capacity (Q_m, mg/g) and Langmuir constant (b, L/mg) values obtained from a Langmuir isotherm, coupled with film diffusion around the resin particle and internal diffusion within the particle, was used to predict concentration change of boron against time. Finally, experimental results were compared with the modelling data for different ionic strength mediums to determine the diffusivity of boron inside the resin and mass transfer coefficients.