沸石吸附废水中磷污染物的研究

含磷化学物质的普遍使用以及目前很低的污水处理率．导致含磷废水大量排放．水体富营养化和水污染日益严重,采用合成的13X沸石,作为一种新型磷吸附剂．研究其在不同吸附时间、水体pH值、沸石用量和振荡速度等条件下对水体中磷的吸附规律。研究表明．该沸石作为废水除磷吸附剂具有很好的发展前景。     

抗硬水性捕收剂的合成及浮选性能研究

以合成的醚烷基磷酸酯作捕收剂,对磷灰石和方解石进行浮选试验,结果表明该捕收剂适合于在弱碱性介质中使用, 有较好的抗硬水性。对磷矿石的浮选效果比使用脂肪酸 （皂） 作捕收剂的指标好, Ｎａ２ Ｃ Ｏ３ 用量显著降低。     

天然沸石制备4A沸石工艺探索

对六个天然沸石制备４Ａ沸石工艺方案进行了探索性试验,得出了两个较好的工艺方案,并对４Ａ沸石制备过程的主要影响因素进行了较详细的分析,为今后进一步研究指明了方向。     

Removal of Phosphate from Aqueous Solution Using Zeolite Synthesized from Fly Ash by Alkaline Fusion Followed by Hydrothermal Treatment

The removal of phosphate from aqueous solution by the adsorption process using zeolite synthesized from fly ash was investigated in this study. The XRD patterns revealed that the major crystalline phase of the synthesized zeolite was gismondine. The phosphate immobilization capacity (PIC) increased significantly from 52.7 mg/g of fly ash to 102.9 mg/g of synthesized zeolite after conversion. The batch experiments were conducted to investigate the effect of pH, initial phosphate concentration, and adsorbent amount. The maximum adsorption capacity was obtained at the pH value of 7.0. The adsorption process followed Ho' pseudo-second-order model, and both liquid film and intra-particle diffusion were the rate-controlling step for the process. The adsorption equilibrium data had been analyzed by Langmuir, Freundlich, Radlich-Peterson, Koble-Corrigan, Tempkin, Dubinin-Radushkevich, and Generalized models. The results showed that the Langmuir model gave the best fit. The process was also found to be endothermic. The maximum phosphate adsorption capacity obtained was 132.02 mg/g (30°C), 156.36 mg/g (40°C) and 184.17 mg/g (50°C), respectively, suggesting that the synthesized zeolite is a promising material and can be used to remove phosphate from wastewater.     

Zeolite titanium beta: a selective and water resistant catalyst in Meerwein-Ponndorf-Verley-Oppenauer reactions

Aluminium-free zeolite titanium beta was found to be a selective and water stable catalyst in the Meerwein-Ponndorf-Verley reduction of alkylcyclohexanones and the Oppenauer oxidation of alkylcyclohexanol. 4-t-butyl- and 4-methylcyclohexanone were reduced with > 98% selectivity to the cis-alcohol. The high stereoselectivity is explained by transition-state selectivity.     

Mesoporous Material from Zeolite

Zeolite/mesoporous molecular sieve composites (ZMC) are made using zeolites as silica-alumina source. XRD patterns of the ZMC show the peaks for both zeolite and mesoporous molecular sieve with hexagonal symmetry. Morphology of the ZMC is different from that of a physical mixture of the two components. Unlike Al-containing mesoporous molecular sieves, the ZMC shows a strong acidity like zeolites. The activity of cracking of n-hexane for ZMC was higher than that of the zeolite. These products are expected to be useful for catalysts and adsorbents for their acidity and pore size.     

4A分子筛对三聚氰胺磷酸盐/季戊四醇阻燃PP性能的影响

采用三聚氰胺磷酸盐（MP）与季戊四醇（PER）做阻燃剂制备了阻燃聚丙烯（PP）,研究了4A分子筛对MP和PER阻燃PP性能的影响,并通过热失重分析（TGA）对材料进行了表征。结果表明：少量的4A分子筛可以明显提高MP／PER阻燃PP的阻燃性能。当MP与PER的质量分数分别为9．0％和6．0％,4A分子筛的质量分数为2．0％时,可以制得氧指数高达34．0％并具有较好力学性能的无卤阻燃PP。TGA结果表明：4A分子筛加入到MP／PER阻燃PP中,可起到促进成炭的作用。     

磷酸二铵装置生产粒状磷酸一铵技术探讨

通过对磷酸二铵装置生产粒状磷酸一铵的技术进行探讨,采用预中和+管式反应器生产工艺路线,并对相关工艺指标进行系统性调整,可以用磷酸二铵生产装置生产粒状磷酸一铵。对工艺指标的优化进行了论述,确定了主要工艺控制条件。     

粉煤灰合成分子筛与分子筛吸附金属的研究进展

综述了将粉煤灰合成沸石分子筛,总结了几种方法合成分子筛的特点和优点。为了提高分子筛的结晶度和得到预期的分子筛种类,论文讨论了由粉煤灰合成分子筛的几种影响因素,以及简述了分子筛对几种放射性金属吸附的方法和意义,并对分子筛的应用进行了展望。     

沸石吸附处理含磷废水的实验研究

静态吸附状态下对人造沸石处理含磷模拟废水进行了实验研究,探讨了沸石用量、磷初始浓度、吸附时间、温度及pH对除磷效果的影响。结果表明,不同磷初始浓度,沸石除磷效果也不同,当废水含磷（以P20s汁）为16mg^-1。时,最佳除磷条件是：沸石质量浓度为18g,L,废水pH为6．8在右,吸附时间为20min,30℃条件下,磷去除率可达98％,沸石作为废水除磷吸附剂具有很好的发展前景。     

用叶蜡石合成Y型沸石的研究

用福州叶蜡石，在适量补硅的条件下，可合成出Ｙ型沸石产物，用ＸＲＤ进行了表征，其硅铝比为４．１－５．０，每克叶蜡石可制出１．２克产品，对焙烧和合成过程进行分析和讨论，试验结果表明，叶蜡石作为合成Ｙ型沸石的廉价原料，有良好的应用前景。     

Adsorption of Congo Red from Aqueous Solution on Surfactant-Modified Zeolites with Different Coverage Types: Behavior and Mechanism

A series of surfactant-modified zeolites (SMZs) were prepared by loading various amounts of cetylpyridinium bromide (CPB) onto the external surface of natural zeolites, and their CPB coverage types were determined by comparing the loading amounts of cetylpyridinium (CP⁺) and bromide (Br^?). The behavior and mechanism of Congo red (CR) adsorption onto SMZs with different coverage types were investigated. The SMZ was effective for the removal of CR from aqueous solution. The SMZ with higher CP⁺ loading amount exhibited higher CR adsorption capacity. The amount of CR adsorbed on SMZ was found to increase with an increase in contact time and initial dye concentration but was found to decrease with increasing adsorbent dosage. Coexisting Cu(II) in solution favored CR adsorption onto SMZs. The kinetic data of CR on SMZs followed a pseudo-second-order model. The equilibrium adsorption data of CR on SMZs were well described by the Langmuir isotherm model. For SMZ with monolayer coverage, hydrophobic interaction was the main mechanism for CR adsorption. For SMZ with bilayer coverage, anion exchange, and organic partitioning were the main mechanisms for CR adsorption. For SMZ with patchy bilayer coverage, anion exchange, organic partitioning and hydrophobic interaction were the main mechanisms for CR adsorption.     

粉煤灰沸石合成转化的研究

综述了以粉煤灰为原料合成沸石的方法,包括传统的湿法合成-水热合成法,干法合成-碱熔法、盐熔法,二步合成法（两步水热合成法,碱熔水热混合法,微波辐射合成法,晶种添加法）等工艺,分析了影响粉煤灰沸石转化的各种因素,如固液比、SiO2/Al2O3比例、反应温度、晶化时间等。     

矾山磷矿浮选药剂及精矿除铁镁研究

对氧化石蜡皂,Ｈ９０７,ＲＭ－２及自制捕收剂分别进行了试验,结果表明自制捕收剂起泡性好,捕收能力强,浮选温度低,缺点是泡沫粘性大。此外还对降低精矿中铁镁杂质含量进行了研究,发现硅酸钠是提高精矿品位和降低铁镁等杂质的有效抑制剂。     

Effect of nitrogen and water uptake on yield of wheat

For 2 years, field experiments were conducted to study the direct and interactive effects of water and nitrogen uptake at different growth stages on grain yield of wheat, grown on coarse textured alluvial soil of Ludhiana. Twelve treatments comprising 3 irrigation regimes and 4 rates of N were imposed. The N and irrigation regimes showed significant interaction, especially during the drier year. Grain yield was better explained with water uptake and N uptake, when partitioned over different growth stages than with total uptake. The sensitivity factor for water uptake was higher at the reproductive stage ( = 1.60) than at the vegetative ( = 1.05) and maturation ( = 0.38) stages. Contrary, yield was more sensitive to N uptake during the vegetative stage than the reproductive and the maturation stages. Sensitivity of grain yield to water uptake was higher at higher N application rates. Yield predictability was much better (R² = 0.98) when N and water uptake at different growth stages were combined.     

Voltammetric Response and Determination of an Anti-Inflammatory Drug at a Cationic Surfactant-Modified Glassy Carbon Electrode

Electrochemical oxidation of thiosalicylic acid in the presence of cationic surfactant, cetyl trimethylammonium bromide (CTAB), at a glassy carbon electrode was investigated. The electrochemical response of a modified sensor towards thiosalicylic acid determination was studied by the means of cyclic voltammetry, linear sweep voltammetry and differential pulse voltammetry (DPV). The liquid phase oxidation of thiosalicylic acid in the presence of CTAB leads to a notable enhancement in the peak current and a lowering of the peak potential. The electrochemical process was observed to be adsorption-controlled, irreversible and involves oxidation of one electron. Effects of anodic peak potential (E _p), anodic peak current (I _pa) and heterogeneous rate constant (k ⁰) were calculated. The linear response was obtained in the range of 1.0 µM–1.0 mM with a detection limit of 113 nM.     

天然沸石制备4A沸石分子筛的条件研究

以天然沸石为原料制备4A沸石分子筛,探讨了不同碱溶条件和晶化条件对制备4A沸石分子筛的影响,通过生物显微镜与X-射线粉末衍射法(XRD)对各因素条件下的产品进行了表征,确定出最佳的制备条件,联用红外光谱(FTIR)、扫描电镜(SEM)对最佳条件下的产品进行了表征。结果表明:天然沸石在碱溶浓度为9%、水浴温度为60℃下碱溶2h,冷却后补铝并在水浴温度为90℃下晶化6h,可得到结晶度较好的4A沸石分子筛。     

Zeolite nanocrystals prepared from zeolite microparticles by a centrifugation-assisted grinding method

Different sizes of zeolite nanocrystals were fabricated from zeolite microparticles using a centrifugation-assisted grinding method. The zeolite nanocrystal formation can be attributed to the Al₂O₃ bowl mill generation of mechanical stress that fractured zeolite microparticles into smaller fragments. In the present study, the smaller fragments had a wide distribution of size and morphology. Therefore, different sizes of zeolite nanocrystals could be recovered from these smaller fragments by varying the centrifugation process. Zeolite nanocrystal product yields were measured by periodically recovering the nanocrystals from the smaller fragments based on milled zeolite powder. The larger crystals of zeolite were typically irregular in shape, whereas the smaller zeolite nanocrystals tended to be spherical. High product yield of the zeolite nanocrystals was obtained by periodically removing nanocrystals from the milled zeolite powder and recycling the large zeolite particles. Thus, the results from this new hybrid process suggest that it can be used to fabricate differing sizes of zeolite nanocrystals. In addition, the size of the recovered zeolite nanocrystal products was narrow, and the initial zeolite nanocrystal structure was not destroyed by the mechanical stress.