ATO/APU纳米复合透明隔热涂料的制备与性能研究

以纳米氧化锡锑(ATO)水性浆料为隔热材料,水性聚氨酯树脂(APU)为成膜物质制备出ATO/APU纳米复合透明隔热涂料。对悬浮ATO粒子的分散稳定性、ATO/APU复合涂膜的物理性能、可见光-近红外透射光谱透过率、隔热性能进行研究。结果表明,纳米ATO粉体通过偶联剂KH-550改性后,与APU复合制得了分散稳定的纳米复合涂料;ATO/APU复合涂料不仅具有良好的成膜性能,而且在保持可见光透过率83.0%时,红外阻隔率达到70%,隔热后温差能保持在6℃左右,复合涂料具有良好的隔热性能。     

亟待开发的无机电子化学品

综述了半导体用过氧化氢、氢氟酸、三氧化二锑和二氧化硅薄膜等超细高纯无机电子化学品 ,印刷电路板和电池方面用的高纯二氧化硅、五氧化二锑和二氧化锰等无机电子化学品 ,介绍了超纯过氧化氢、超纯氢氟酸、五氧化二锑和γ 二氧化锰的制备方法。     

低砷高锑阳极的铜电解生产

介绍了我国北方某电解铜厂,在很长一段时间内,采购的阳极含砷较低而含锑较高。针对这种阳极板,采取了合理控制电解液成分、合理选用添加剂种类和控制用量、提高电解液温度、改变电解液循环方式、由常规电解改为周期反向电解等技术措施和完善操作方法,使电铜的合格率达到了100%。     

锑的界面环境化学行为的研究进展

锑是一个可长距离输送的全球性有毒元素;但锑的研究最近才引起国际社会的关注。与其它金属如汞、铅、镉和砷等相比,国际上锑的研究开展得相对较少。为了揭示锑的全球性污染程度、循环过程及其对生态环境的影响,急需开展深入研究。文章概述了锑的概况,污染途径和环境危害、前人在锑的界面过程方面的研究成果,分析了存在的科学问题,凝练了进一步研究的方向、思路和方法,并对锑的研究前景进行了展望。     

Solid-state reactivity of iron molybdate artificially contaminated by antimony ions and its relation with catalytic activity in the selective oxidation of isobutene to methacrolein

Catalysts were prepared by impregnation of Fe₂(MoO₄)₃ with different quantities of antimony butoxide. BET surface area measurement, XRD, Mössbauer spectroscopy, CTEM-AEM, XPS and ISS were used to characterize phase and surface architectures and their changes after calcination and catalytic reaction. Before calcination, antimony was present as pure oxide or hydroxide, partly as particles and partly as an incomplete monolayer on the surface of Fe₂(MoO₄)₃. After calcination at 400°C, antimony got detached from the Fe₂(MoO₄)₃ surface and aggregated very intensively, partly as Sb₂O₄ and partly, through reaction with the iron molybdate, as a mixture of distorted FeSbO₄ and MoO₃. After reaction or calcination at 500°C, more distorted FeSbO₄ and MoO₃ are formed, separated from Fe₂(MoO₄)₃. Selective oxidation of isobutene to methacrolein was carried out on the calcined material. Impregnated catalysts show considerably improved catalytic performances compared to the pure Fe₂(MoO₄)₃ phase or mechanical mixtures of it with α-Sb₂O₄. The catalytic performances are explained by several catalytic cooperations via spillover oxygen. These cooperative effects involve all the oxide phases present in the material having worked as catalyst: Fe₂(MoO₄)₃ (pure or possibly contaminated by small amounts of antimony oxide), FeSbO₄, MoO₃ and Sb_yO_x.

     

Sb(V) removal from copper electrorefining electrolyte: Comparative study by different sorbents

Removal of Sb(V) from copper electrolyte by different sorbents such as activated carbon, bentonite, kaolin, resin, zeolite and white sand was investigated. Adsorption capacity of Sb(V) removal from copper electrolyte was as follows: white sand < anionic resin < zeolite < kaolin < activated carbon < bentonite. Bentonite was characterized using FTIR, XRF, XRD, SEM and BET methods. The results show specific surface area of 95 m²/g and particles size of 175 nm for bentonite. The optimum conditions for the maximum removal of Sb are contact time 10 min, 4 g bentonite and temperature of 40 °C. The adsorption of Sb(V) on bentonite is followed by pseudo-second-order kinetic (R²=0.996 and k=9×10^?5 g/(mg·min)). Thermodynamic results reveal that the adsorption of Sb(V) onto bentonite from copper electrolyte is endothermic and spontaneous process (ΔG^Θ=–4806 kJ/(mol·K). The adsorption data fit both the Freundlich and Langmuir isotherm models. Bentonite has the maximum adsorption capacity of 10000 mg/g for adsorption of Sb(V) in copper electrolyte. The adsorption of Zn, Co, Cu and Bi that present in the copper electrolyte is very low and insignificant.     

Sintering of Zinc Oxide Doped with Antimony Oxide and Bismuth Oxide

The phase change, densification, and microstructure development of ZnO doped with both Bi₂O₃ and Sb₂O₃ are studied to better understand the sintering behavior of ZnO varistors. The densification behavior is related to the formation of pyrochlore and liquid phases; the densification is retarded by the former and promoted by the latter. The pyrochlore phase, whose composition is Bi_3/2ZnSb_3/2O₇, appears below 700°C. The formation temperature of the liquid phase depends on the Sb/Bi ratio: about 750°C for Sb/Bi < 1 by the eutectic melting in the system ZnO—Bi₂O₃, and about 1000°C for Sb/Bi > 1 by the reaction of the pyrochlore phase with ZnO. Hence, the densification rate is determined virtually by the Sb/Bi ratio and not by the total amount of additives. The microstructure depends on the sintering temperature. Sintering at 1000°C forms intragrain pyrochlore particles in ZnO grains as well as intergranular layers, but the intragrain particles disappear at 1200°C by the increased amount of liquid phase, which enhances the mobility of the solid second phase.     

氯氧化锑阻燃剂的制备、阻燃机理及其阻燃应用

对氯氧化锑的不同制造方法作了详细比较 ,指出开发新的生产工艺是把氯氧化锑阻燃剂推向市场的关键 ;在分析氯氧化锑阻燃机理的基础上 ,探讨了其阻燃应用。     

Effect of Sb addition on SbxSn1-xS thin films: The structural,morphological, and linear/nonlinear optical changes for optoelectronic applications

The current paper reports the changes in the structural and optical properties of antimony-doped tin sulfide ternary (Sb_xSn_1-xS) (x = 0, 0.05, 0.1, 0.15, 0.2) thin films synthesized by the thermal evaporation technique on a glass substrate. Structural characterization techniques such as X-ray diffraction and Raman spectroscopy of the prepared sample revealed that the thin films are crystalline in nature. The nanoflake-like structure was found from the surface morphological analysis performed by field emission scanning electron microscopy. The concentration of the compositional elements was confirmed from the energy dispersive X-ray analysis. The linear and nonlinear optical parameters were calculated by using the transmission data obtained from UV–vis spectroscopy in the range of 800–1100 nm. The optical measurements showed an increase in transmittance and shifting of the absorption edge. The optical bandgap increased (1.239–1.378 eV) and the refractive index decreased with the increase of Sb concentration, satisfying the Moss rule. The nonlinear susceptibility and the nonlinear refractive index (n₂) decreased with Sb content. The changes in both linear and nonlinear parameters by varying the antimony doping concentration could be helpful for controlling the optical properties of Sb_xSn_1-xS thin films and could be a suitable candidate for many photonics and optoelectronic applications.     

The role of Sb and Nb in rutile-type Sn/V/Nb/Sb mixed oxides, catalysts for propane ammoxidation to acrylonitrile

This paper describes the role of Sb and Nb, components of Sn/V/Nb/Sb mixed oxides catalysts for the gas-phase ammoxidation of propane to acrylonitrile. In samples without Nb and with atomic ratios Sn/V/Sb 1/0.2/x (x = 0 to 3), Sb in the form of amorphous oxide is necessary in order to obtain an active and selective catalyst. However, during reaction the dispersed Sb oxide segregates to α-Sb₂O₄, and the yield to acrylonitrile decreases considerably. The addition of Nb gives rise to the formation of Nb-containing SbO_x and non-stoichiometric rutile-type V/Nb/Sb mixed oxides. The presence of these compounds enhances the catalytic activity and the selectivity to acrylonitrile. Moreover, the catalyst shows a stable catalytic performance, with no segregation of α-Sb₂O₄.