Fe^3＋／HZSM-5分子筛催化合成乙酸乙酯

以固体超强酸Fe^3 ／HZSM-5为催化剂，以乙醇和乙酸为原料合成乙酸乙酯。考察了催化剂用量、酸醇比、反应温度及反应时间对酯化率的影响。结果表明，催化剂用量为(重量)反应液重的5％，酸醇比为2．5：1，反应温度为110-130℃，反应时间为3h．酯收率为93％．     

酸性镀锌溶液中硼酸分析方法的改进

酸性镀锌溶液中硼酸为多元弱酸，不能直接用NaOH滴定，只能通过加入多烃基有机物，与硼酸生成较强的络合酸方可滴定，用酚酞作指示剂，终点变化不易观察，导致结果产生误差。本方法加入甲基红，与酚酞成混合指示剂，实现了终点的突跃。另外加入草酸钾掩蔽Fe^2 、Fe^3 等杂质，有效地阻碍了Zn^2 与NaOH的反应，不影响结果的精度。     

铁的电解氧化处理的基本原理及其对电混凝的影响

本文讨论了通过电解产生的铁，发生在电解期间和电解后的过程反应和将Fe^2＋氧化成Fe^3＋的溶解氧的自然氧化。     

国内外金红石矿资源开发利用现状

金红石是自然界较常见矿物。单形常为四方柱和四方双锥、有时出现复四方柱和复四方双锥。常具平行于C轴的柱面条纹，可见膝状双品、三连晶及环状双晶。化学成分，理论上TiO2为100％，Ti-60，O-40；但在自然界中，常含Fe^2＋、Fe^3＋、Nd^3＋、Sn^4＋，Th、Y、Cd、Ba、Be及稀土元素；富铁者称铁金红石；富铌、钽（同时常富含铁）者，当铌〉钽称为铁金红石，当钽〉铌时称钽铁金红石。颜色常呈淡黄、红、棕红、棕及黑色等。     

有机酸性含氰废水处理技术研究

以酸性含氰废水为研究对象,在烧杯实验的基础上,对实验现场以中试规模较深入地研究了UV—Fenton反应体系中H2O2浓度、m（H2O2）：m（Fe^2＋）比值、pH值等对处理效果的影响,确定了最佳操作条件：H2O2投加量范围为3500-4000mg／L;Fe^2＋的含量应较低,m（H2O2）：m（Fe^2＋）〉100：1;pH值范围为3．5～4．0。     

霉菌在含Cu^2＋废水处理中的试验研究

采用Fenton试剂法对化学需氧量（CODCr）为1000-2000mg／L,pH值为3-9的丁苯橡胶废水进行处理。在Fe^2＋／H2O2（体积比）为9／8,初始废水pH值为3．0-0．15,反应温度为50℃,反应时间为30min的条件下,研究了Fe^3＋,H2PO^-4,     

Fe^3＋-CdS/TiO2复合半导体的光催化性能

采用溶胶-凝胶法制备了一系列不同配比的Fe^3＋-CdS/TiO2光催化材料,利用UV-Vis对其光谱特性进行了表征,以亚甲基蓝（MB）的脱色降解为模型反应,考察了Fe^3＋、CdS/TiO2的制备条件对光催化性能的影响。     

Fe^3＋、Zn^2＋共存、Mn^2＋、Cu^2＋、Ca^2＋体系中Ca^2＋、Mg^2＋、Mg^2＋等离子的测定

叙述了Fe^3 、Zn^2 、Mn^2 、Cu^2 、Ca^2 、Mg^2 等离子共存体系中采用六次甲基四胺一铜试剂沉淀除去Fe^3 、Zn^2 、Mn^2 、Cu^2 等干扰离子．用EDTA滴定钙镁的方法，该方法钙的回收率在99．7％～100．3％；镁的回收率在100．0％～100．4％，标准偏差为0．022。     

Fe3+和Al3+对阻垢效果的影响

本研究采用静态法评价了在Fe^3 和Al^3 存在下，各种比较典型的单体阻垢剂(包括有机膦酸盐和聚羧酸盐)对碳酸钙和硫酸钡的阻垢能力。实验研究表明：对于阻碳酸钙垢来说，各种阻垢剂受Fe^3 和Al^3 的影响不大；对于阻硫酸钡垢来说，所有药剂在Al^3 存在下其阻垢性能均大幅度下降；而Fe^3 对阻硫酸钡的影响则可以分为三种情况：(1)在所考察的药剂中，大部分药剂的阻钡垢的效果均大幅度降低；(2)氨基三甲叉膦酸(ATMP)受其Fe^3 和Al^3 的影响不大；(3)羟基叉二膦酸(HEDP)的阻钡垢的能力有所增加。     

掺杂铁TiO2纳米微粒的制备及光催化性能

以钛酸四丁酯为前驱体,采用溶胶-凝胶法制备了Fe^3＋掺杂改性纳米TiO2光催化剂,通过纯TiO2和掺铁TiO2分别做光催化荆时甲基橙溶液在紫外光下的光催化降解试验发现,掺杂铁离子可以有效提高TiO2的光催化活性,结果表明：选用Fe^3＋掺杂量为0．05％,煅烧温度在500℃下得到的Fe^3＋．TiO2催化剂,在甲基橙溶液pH值为3,催化剂投加量为1g／L时,其光催化活性达到最佳效果。     

Chelation of Cu(II), Zn(II), and Fe(II) by Tannin Constituents of Selected Edible Nuts

The tannin fractions isolated from hazelnuts, walnuts and almonds were characterised by colorimetric assays and by an SE-HPLC technique. The complexation of Cu(II) and Zn(II) was determined by the reaction with tetramethylmurexide, whereas for Fe(II), ferrozine was employed. The walnut tannins exhibited a significantly weaker reaction with the vanillin/HCl reagent than hazelnut and almond tannins, but the protein precipitation capacity of the walnut fraction was high. The SE-HPLC chromatogram of the tannin fraction from hazelnuts revealed the presence of oligomers with higher molecular weights compared to that of almonds. Copper ions were most effectively chelated by the constituents of the tannin fractions of hazelnuts, walnuts and almonds. At a 0.2 mg/assay addition level, the walnut tannins complexed almost 100% Cu(II). The Fe(II) complexation capacities of the tannin fractions of walnuts and hazelnuts were weaker in comparison to that of the almond tannin fraction, which at a 2.5 mg/assay addition level, bound Fe(II) by ~90%. The capacity to chelate Zn(II) was quite varied for the different nut tannin fractions: almond tannins bound as much as 84% Zn(II), whereas the value for walnut tannins was only 8.7%; and for hazelnut tannins, no Zn(II) chelation took place at the levels tested.     

单宁与土壤中铁元素的可给性

报道了在土壤中加入单宁溶液以解决植物缺铁问题的方法。通过植物单宁与 Fe3+ 的配合作用和氧化还原作用 ,改变土壤中铁元素的氧化还原电位 ,提高土壤中 Fe2 +离子的浓度 ,以增加土壤中铁元素的可给性。用等离子体发射光谱仪 ( ICP)测定了患有缺铁症状苹果树的树液中 ,在施用单宁溶液前后铁离子浓度的变化 ,观察了单宁与土壤中铁元素相互作用后的结果 ,讨论了两者的作用机理 ,有效解决了一些植物生长过程中的缺铁问题 ,为大面积的田间应用提供了一些依据     

过氧化氢氧化玉米秸秆酶解残渣制备螯合微肥的研究

利用过氧化氢在不同条件下对玉米秸秆制备生物乙醇的酶水解残渣进行氧化改性,氧化产物分别与Fe2+、Cu2+、Zn2+、Mn2+四种离子进行螯合反应制备微肥。探讨了不同氧化条件对金属离子螯合率的影响,并确定了适宜的氧化工艺条件:过氧化氢用量20%,温度70℃,pH值为11,时间60 min,此时残渣溶出率为32.5%,氧化产物对Fe2+、Cu2+、Zn2+、Mn2+四种金属离子的总螯合率分别为5.0%,4.5%,3.9%,4.0%。通过正交试验分析,氧化条件对酶解残渣的溶出率和总螯合率的影响主次顺序为:pH值,过氧化氢用量,温度。     

单宁改性生漆复合涂料的制备及其性能研究

通过添加单宁和金属离子催化剂,对生漆进行改性制备复合涂料,研究金属离子种类、单宁添加量、反应时间、反应温度对单宁改性生漆复合涂料成膜性能的影响。研究结果表明,生漆中加入其质量1/5倍的20%FeCl3乙醇溶液反应40min后,再添加生漆质量8%的单宁,在60℃下反应3h得到的改性生漆成膜性能最佳,干燥时间缩短为52h,附着力为3~4级,耐冲击力为30kg/cm,硬度为2H。与原生漆相比,改性生漆耐碱性提高了3倍,耐受温度提高了2倍;红外光谱分析表明,生漆中的漆酚和单宁的酚羟基发生了醚化反应,从而改善了漆膜特性。     

Adsorption mechanism of heavy-metal ion by microspherical tannin resin

The spherical tannin resin (STR) resulting from the reaction between Mimosa (Acacia Mollissima) tannin (condensed-type tannin) and formaldehyde was very porous. The specific surface area of the STR made from 37.5% of tannin was 139.2 m²/g (1 g of the resin in this is wet resin corresponding to 1 g of dried resin). Properties such as specific surface area and average pore radius could be controlled by adjusting the tannin concentration. The apparent activation energy of Cu²⁺ ion adsorption by STR was 3 kcal/mol, and that of Cr⁶⁺ ion was 2 kcal/mol. Since the energy was small, we concluded that the adsorption of metal ions was not influenced significantly by the adsorption temperature. The heat of adsorption for Cu²⁺ ions was only 1.6 kcal/mol, which suggests that the adsorption was a physical phenomenon. It was thought that the diffusion of heavy-metal ions into the porous resin was the rate-determining step of the adsorption since the elution profile of the column method was analogous to the profile of active carbon, which adsorbs physically, the heavy metal ions gradually leaking through the column. The surface and cross section of the STR were observed before and after Cu²⁺ ion adsorption with the scanning electron microscope. The pores of the spherical resin were clogged with adsorbed copper, suggesting that the Cu²⁺ ions were adsorbed during the formation of a multimolecular layer. The adsorption may therefore have been due to physical attractive forces. The rate of adsorption and adsorption isotherms of Cu²⁺ ions from copper salts having various anions was found to vary depending on the type of anion. These phenomena were not thought to be due to the properties of the spherical resin but to differences in the hydration state of copper ions.     

EDTA插层水滑石的合成及其对Cd2+的去除性能研究

利用EDTA对重金属离子的螯合作用,将其作为有机阴离子插入到镁铝水滑石的层间,采用共沉淀法制备了复合层状材料EDTA.Mg-Al LDH。通过正交实验确定了NaOH投加量为理论计算值的1.2倍时,合成物的层间阴离子以EDTA4-形式稳定存在。EDTA.Mg-Al LDH处理56 mg/LCd2+溶液的最佳处理条件为:水滑石质量浓度5.0 g/L,反应时间60 min,去除率可达98.20%。并与以无机阴离子Cl-作为插入离子制备的Cl.Mg-Al LDH对56 mg/L的Cd2+溶液的去除率进行了比较,由于层间阴离子EDTA4-对重金属强烈的螯合能力,EDTA.Mg-Al LDH对水中Cd2+的去除效率大大高于Cl.Mg-Al LDH。     

Fenton和类Fenton技术处理水中盐酸四环素试验研究

为了对比研究Fenton和EDTA-Fe~(3+)、 Fe~(3+)、 Fe~(6+)类Fenton试剂对盐酸四环素的氧化效果,考察了pH值、反应时间、 H_2O_2与铁离子的物质的量比、试剂投加量对盐酸四环素处理效果的影响。结果表明,pH值对EDTA-Fe~(3+)类Fenton氧化效果影响较小,Fenton、 Fe~(3+)和Fe~(6+)类Fenton技术最适pH值范围分别为3~5、 4~7和4。Fenton反应速度最快,20 min基本稳定,其次是EDTA-Fe~(3+)类Fenton反应,Fe~(6+)类Fenton反应速度最慢。Fenton、Fe~(3+)和Fe~(6+)类Fenton反应中H_2O_2与铁离子的最佳物质的量比为10∶1, EDTA-Fe~(3+)类Fenton反应中H_2O_2与铁离子的最佳物质的量比为13∶1。在最优试验条件下,盐酸四环素的降解效率依次为:Fenton> Fe~(3+)类Fenton> EDTA-Fe~(3+)类Fenton> Fe~(6+)类Fenton;4种反应试剂对COD_Cr的去除效率均不高,处理效果最好的是Fe~(3+)类Fenton试剂,COD_Cr去除率为21.4%,而EDTA-Fe~(3+)类Fenton处理后COD_Cr浓度高于进水。紫外-可见吸收光谱表明盐酸四环素在4种反应体系中均迅速下降,有小分子产物生成。4种试剂处理后出水色度均较高,后续需要脱色处理。     

Methods for preparation of absorbent microspherical tannin resin

Tannin beads formed by reaction of Mimosa tannin (condensed-type tannin) with formaldehyde in nonpolar polybutenous medium were microspherical resins. Resins prepared with 37.5% tannin concentration were porous spherical resins with 139.22 m²/g of surface area (adsorption method of iodine in n-hexane, 2.1 m²/g for the dried beads by the Braunauer-Emett-Teller (BET) method) and were strong enough to withstand use on a column. The spherical resin adsorbed 3.7 mmol of Cr⁶⁺ ions per one gram dry weight of resin (by batch method), this adsorption being comparable to commercial adsorbent.     

金属离子对彩色成像过程的影响

通过测量和计算彩色单层片中成色剂的照相活性、偶合效率以及漂白前银密度等参数,研究了在分散四当量成色剂青(Ⅰ)时掺入金属离子Mg~(2+)、Zn~(2+)、Fe~(3+)和Cu~(2+)对彩色青单层片的成像过程中各个化学反应的影响。本实验的结果表明,成色剂中加入的金属离子Cu~(2+)和Fe~(3+)对成像过程的初始反应中的Ag影像形成产生不利的影响,但它们能促进偶合过程中青(Ⅰ)与显影剂氧化产物作用所生成的隐色体转变成染料的速率。Mg~(2+)和Zn~(2+)的加入主要是对偶合过程中青(Ⅰ)的偶合效率产生不利的影响。上述原因的综合影响,最终降低了彩色单层片的感光度。     

多元醇法制备纳米Fe3O4的研究

为了研究液相多元醇法制备金属纳米粒子,以氯化亚铁为前驱物,1,2-丙二醇为还原剂,意外获得了Fe3O4纳米粒子。通过X射线衍射分析标定了获得样品的物相为面心立方结构的Fe3O4,用透射电镜观察了样品的形貌,其颗粒形貌为球形,大小为50—70 nm。根据标准状态下氧化-还原反应的电池电动势研究了反应机理,结果表明,Fe2+发生了歧化反应,反应主要向Fe2+被氧化的方向进行,产物为纳米Fe3O4。