天然沸石在建材领域中的应用研究进展

本文在简述天然沸石结构和性能的基础上,对近年来天然沸石在水泥、混凝土、涂料、陶瓷、橡塑等建筑材料中的应用研究现状进行了综述,其中以沸石的离子交换特性和选择吸附性能为着眼点,重点介绍了天然沸石在水泥混凝土工业中的研究现状.     

改性沸石在废水处理中的应用

针对改性沸石在水处理领域中研究应用的现状,分别对天然沸石的改性方法,改性沸石对废水中的重金属离子、含氧酸阴离子及有机物的处理性能等方面作了详细的介绍,指出所存在的问题,并展望了改性沸石在水处理领域的应用前景。     

天然沸石去除煤化工废水中氨氮的研究

采用天然沸石去除煤化工废水中的氨氮,考察了沸石投量、吸附时间、温度、p H等因素对氨氮去除率的影响。另外对天然沸石进行改性,对比了酸、碱、盐、微波、焙烧等方式对天然沸石吸附性能的影响。结果表明,天然沸石对煤化工废水中的氨氮有较好的去除效果,而碱改性可以明显提高沸石的吸附性能。采用HCl溶液在高温条件下解吸饱和天然沸石,可使沸石的吸附能力得以再生。     

天然沸石和改性沸石在废水处理中的应用研究

综述了天然沸石和改性沸石在废水处理中的脱氮、除磷、除氟、除有机污染物和重金属污染物等的应用研究;探讨了沸石的高温改性、酸改性、碱改性、盐改性和复合改性等的改性沸石方法;并对能够使沸石再生的物理法、化学法、电化学法和生物法进行了比较。同时,对天然沸石和改性沸石在废水处理中的进一步发展提出了一定的看法和思考。     

天然沸石和改性沸石在废水处理中的应用研究

综述了天然沸石和改性沸石在废水处理中的脱氮、除磷、除氟、除有机污染物和重金属污染物等的应用研究;探讨了沸石的高温改性、酸改性、碱改性、盐改性和复合改性等的改性沸石方法;并对能够使沸石再生的物理法、化学法、电化学法和生物法进行了比较。同时,对天然沸石和改性沸石在废水处理中的进一步发展提出了一定的看法和思考。     

沸石吸附处理含磷废水的研究进展

沸石是一种优良的含磷废水处理剂,在水处理领域将有广阔的应用前景,文章介绍了天然、改性及合成沸石去除废水中磷的应用现状及进展,并在此基础上提出了加强各种天然沸石的成分,结构和性能研究,加强对天然沸石的改型改性工艺技术研究,扩大沸石在含磷废水处理中的应用范围。     

皖南天然沸石在水处理中的应用研究

天然沸石因骨架带有负电荷 ,笼中含有平衡骨架负电荷的 Na+、Ca2 +等可交换的碱或碱土金属离子 ,使其具有离子交换树脂特性。同时 ,因有发达的孔隙和极性表面 ,天然沸石对极性分子和非极性分子都具有良好的吸附性能。皖南沸石矿以丝光和斜发沸石为主 ,溶出物和有毒害元素含量均很低 ,对水体中的 NH+4- N具有吸附速率快 ,吸附容量大等特点 [1] 。为了扩大天然沸石在水处理及环保等方面的应用范围 ,我们考察了皖南天然沸石对不同水体环境中的 NH+4以及 COD和水中优先控制污染物苯酚等的去除效果。1　实验部分1 .1　材料皖南沸石原矿 ,粉碎…     

钠改性沸石处理氨氮废水及再生的方法

采用钠改性沸石为吸附材料,吸附饱和后通过电解氧化进行再生,能够有效对某印染公司的排放废水中的超标氨氮进行吸附处理,在保证原有污水处理工艺不变的条件下,通过增加设备,使其氨氮能够达到国家或地方规定的污水排放指标。对天然沸石的改性和连续再生,解决了天然沸石性能差、只能一次性使用的问题,大大提升了天然沸石的使用价值。     

沸石的改性及其在废水处理中的应用

沸石作为一种廉价的非金属矿物在废水处理中应用已久,本文针对天然沸石的局限性,提出了沸石的改性方法以及改性后沸石在水处理中的应用和前景。     

天然沸石对高浓度NH4+吸附机理研究

为快速降低高NH₄⁺水源中的NH₄⁺浓度,便于后续生化工艺处理,本研究选用天然沸石作为吸附剂,并考察了影响天然沸石对高浓度NH₄⁺吸附性能的因素;通过研究天然沸石对高浓度NH₄⁺的吸附动力学、等温线和热力学特性,并结合分子动力学模拟,探究了天然沸石对高浓度NH₄⁺的吸附机理。结果表明,当天然沸石投加量为50 g/L、NH₄⁺-N初始质量浓度为4 000 mg/L、温度为35℃、吸附时间为3 h时,天然沸石对NH₄⁺-N的吸附量可达26.94 mg/g。吸附动力学和等温线分析表明,天然沸石对高浓度NH₄⁺的吸附过程更适合用准二级动力学模型和Freundlich模型描述。理论计算和红外光谱表征佐证了氢键和化学吸附作用的存在。天然沸石吸附高浓度N...     

饮用水中的天然有机物去除方法探讨

天然有机物的去除对保证水质是至关重要的。本文阐述了天然有机物的性质和危害 ,并对天然有机物的去除方法进行了探讨     

改性沸石净化废水中有机物的研究

利用经不同温度以及相同浓度、不同改性物质改性后的沸石对废水中COD的去除率测定,结果表明酸、碱、盐改性的沸石对废水中有机物的去除率不同。改性浓度为0.5 mol/L时,NaCl改性沸石去除率最高。在工业生产中,采用NaCl改性沸石处理废水是一种较理想的选择。     

天然沸石用于去除水体中有机污染物的效果

用固定床吸附柱方法研究天然沸石，天然沸石和活性炭配合使用去除水中致色有机物的效果，并考察了它们对苯酚与苯胺的吸附作用，结果表明，天然沸石对自来水中致色有机物有明显去除效果，与活性炭配合使用时，能将自来水中致色有机物基本去除，与活性炭不同，天然沸石地苯酚的吸附能力３成于苯胺。     

The effect of capping with natural and modified zeolites on the release of phosphorus and organic contaminants from river sediment

A microcosm system that included river sediment, water and different zeolite capping materials (natural zeolite, surfactant-modified zeolite (SMZ), or aluminum modified zeolite (AMZ)) was designed to study the effect of capping on the release of phosphorus and three organic pollutants (phenol, pyridine, and pyrene) from the sediment to the overlying water over the course of three month. For the same amount of the three capping materials, the efficiency of phosphorus inactivation was in the order of SMZ>AMZ>natural zeolite. The inactivation of phosphorus was mainly caused by the covering effect, co-precipitation and adsorption by the capping materials. The different zeolites gave different results for the release of phenol, pyridine, and pyrene from the sediment. When natural zeolite was used as the capping material, there was no effect on the release of pyrene and pyridine, whereas capping the sediment with SMZ or AMZ inhibited the release of pyrene and pyridine but to different extents. However, for controlling the release of phenol from the sediment, aluminum modified zeolite was the most efficient material, whereas no effects were observed when natural zeolite or SMZ were used. The different capabilities of the zeolite materials for controlling the release of different organic pollutants are related to the differences in the electrical properties of these pollutants.     

The Adsorption of Arsenic Ions Using Beidellite,Zeolite, and Sepiolite Clays: A Study of Kinetic,Equilibrium and Thermodynamics

Arsenic contamination in drinking water resources is a global problem; therefore, its removal from drinking water has become an important sustainable matter. The adsorption process can be more cost-effective and applicable, especially, if the absorbents used in the process are low-cost natural geo-materials. Beidellite, zeolite, and sepiolite are inexpensive and natural minerals available locally, modified, and used as adsorbents for the removal of arsenic ions from aqueous solutions in batch experiments. The kinetics of the adsorption process was separately tested for the pseudo-first order and pseudo-second order reactions and intra-particle diffusion models. The rate constants of adsorption for all these kinetic models were calculated. The comparison among the models showed that the pseudo second-order model best described the adsorption kinetics. Applied to the experimental equilibrium, at different temperatures were the Langmuir and Freundlich isotherm models. The Langmuir isotherm was used to calculate the adsorption capacities (Q°) of minerals for arsenic ions. The adsorption capacities of these three modified minerals, at different temperatures, ranged from 476 to 841 µg/g. Thermodynamic studies showed that the arsenic uptake reactions by minerals were endothermic and spontaneous in nature. Bottled spring water containing arsenic, sold in markets, was used to conduct the arsenic adsorption study beidellite, zeolite, and sepiolite, minerals which efficiently removed the arsenate ions from the bottled drinking water. The use of modified beidellite, zeolite, and sepiolite as adsorbents in the arsenic ion removal processes is possible, based on the optimum parameters found.     

人造沸石吸附水中金属铜离子研究

研究了人造沸石对水中金属铜离子的吸附。结果表明,人造沸石对金属铜离子有吸附效果。pH值是影响吸附的主要因素,另外时间、人造沸石用量和溶液中金属铜离子浓度都会影响吸附容量。通过红外光谱比较人造沸石和天然沸石的异同,分析人造沸石的优劣势。     

天然有机物对混凝除藻的影响

试验研究了天然有机物(腐植酸、富里酸)对混凝除藻的影响,以及在含有天然有机物水体中混凝除藻的机理.结果表明,天然有机物会与藻细胞争夺絮凝剂,由于天然有机物与PAC亲和力强,PAC优先与天然有机物结合,再与藻细胞结合,当水体中天然有机物含量较多时,混凝除藻效果降低.当腐植酸质量浓度为20.2 mg/L时,藻去除率仅为2....     

Effects of glycol on adsorption dynamics of idealized water droplets on LTA-3A zeolite surfaces

During production of natural gas, glycol may follow the gas stream due to hydrate prevention or glycol dehumidification. Further dehumidification can be achieved by Linde Type A-3A zeolite. Local glycol concentrations can form through adsorption to surrounding clay material or zeolite, thus blocking zeolite windows or contaminating condensed water droplets close to the surface. Idealized nanoscale water droplets and their adsorption dynamics onto zeolite structures were simulated, with and without glycol contamination. Blockage of the zeolite windows was also investigated. Water from contaminated droplets adsorbed slower than uncontaminated droplets due to hindrance caused by glycols adsorbed to the zeolite surfaces, thus decreasing initial water loading rates. The adsorption free energy barrier of water was higher for D4R-terminated zeolite than for alpha cavity-terminated zeolite. Adsorbed glycols blocked zeolite cavities. However, temperature increase resulted in partial desorption of the glycols, while water desorbed at a lower temperature than for glycol.     

Horizontal Flow Filtration Bed: Impact on Removal of Natural Organic Matter and Iron Co-Existing in Water Source

Removal of natural organic matter and iron co-existing in water source is a challenge and a major problem in the developing world where the most commonly applied process in water treatment is pre-chlorination which results in early formation chlorinated by-products. Results from this study proved that horizontal roughing filter system with natural pumice is a promising option for pre-treatment of such waters. The filter recorded average reductions of total and ferrous iron of 39% and 89%, respectively, and trihalomethanes formation potential of 35% after 1 hour and 29% after 6 hours along the filter. Further reductions of 49% and 61% were achieved when the pretreated water was subjected to coagulation.