锌溶法处理Al-Zn-Fe-Si渣分离金属铝

从原理和实验两方面分析了采用锌溶法处理Al—Zn—Fe—Si渣分离金属铝工艺的可行性。Al-Zn、Fe—zn、Si—Zn二元相图表明，当溶解温度在450℃～650℃的范围内，铝在锌中的溶解度比铁、硅大得多。溶Al—Zn—Fe～Si渣的过程中．渣中的铝被锌溶解形成Al-Zn合金液。铁、硅不溶或很少溶解形成浮渣。去渣。得到Zn—Al合金，铝从Al—Zn—Fe—Si渣中分离出来。实验表明：用此法可以将渣中的铝分离得到含铁为0．0043％、硅小于0．05％的锌铝合金，渣中的铝含量从51．68％降低到3．65％．铝的溶解率为74．42％。低温得到的合金含杂质少。

废旧硬质合金的回收——化学法和锌熔法的比较

废旧硬质合金的回收大部分都采用锌熔法和化学法。尽管从费用角度看 ,锌熔法更加有利 ,但在目前世界范围内 ,不用化学法进行“纯化” ,只用锌熔法是不行的。“纯化”将避免不理想的、对质量有害的杂质的积聚。因此 。

Recovery of nickel,cobalt,copper and zinc in sulphate and chloride solutions using synergistic solvent extraction

A number of synergistic solvent extraction （SSX） systems have been developed to recover nickel, cobalt, zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO, Australia. These in- clude （1） Versatic 10/CLXS0 system for the separation of Ni from Ca in sulphate solutions, （2） Versatic 10/4PC system for the separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, （3） Cyanex 471X/HRJ-4277 system for the separation of Zn from Cd in sulphate solutions, （4） Versatic 10/LIX63 system for the separation of Co from Mn/Mg/Ca in sulphate solutions, （5） Versatic 10/LIX63/TBP system for separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, （6） Versatic 10/LIX63 system for the separation of cobalt from nickel in sulphate solutions by difference in kinetics, （7） Cyanex 272/LIX84 system for the separation of Cu/Fe/Zn from Ni/Co in sulphate solutions, （8） Versatic 10/LIX63fFBP system to recover Cu/Ni from strong chloride solutions, and [9） Versatic 10/LIX63 system to separate Cu from Fe in strong chloride solutions. The synergistic effect on metal separation and efficiency is presented and possible industrial applications are demonstrated. The chemical stability of selected SSX systems is also reported.

Solvent extraction of zinc from zinc sulfate solution

The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio （Vσ/Va） of 1.0：1.0, initial pH of 2.0 and stirring speed of 200 r/min. The results show that 75% zinc can be extracted from the zinc sulfate solution when the concentration of zinc is 18.7 g/L after being settled for 10 min. 88.60% zinc can be stripped by 196 g/L sulfuric acid, and zinc ion can be separated from ferric ion.

SOL-GEL SYNTHESIS AND LUMINESCENCE OF GREEN LIGHT EMITTING PHOSPHORS ZN_2SIO4/MN^(2+)

Mn^2＋ doped Zn2SiO4 phosphors were synthesized by sol-gel method, and the influence of zinc source, Mn^2＋ dopant concentration and annealing temperature were investigated. Results show that zinc nitrate based precursor with strong green emission intensities is better than zinc acetate based precursor. The intensity of green light emission reaches a peak at 254 nm when the Mn^2＋ dopant concentration is about 5%（ molar percentage）. Structural details of the phosphors were examined through X-ray diffractometry, thermogravimetric and differential thermal analysis. The result indicates that they are both rhombohedral structures, which remain amorphous below 700 ℃ and crystallize completely around 1000 ℃. The luminescent properties of Zn2SiO4/Mn^2＋ phosphors were characterized by excitation and emission spectra.

Influence of dopant content on morphology and optical constants of ZnO:Na films by sol-gel method

Undoped and Na-doped ZnO films were deposited by sol-gel method.The effects of sodium incorporation on structure,surface morphology and optical constants of the films were investigated.X-ray diffraction patterns show the hexagonal wurtzite polycrystalline structure and that the sodium incorporation leads to the change in the structural characteristics of ZnO films.The SEM observations show that the surface morphology of the films is affected by the sodium incorporation.The transmission spectra show that the average transmittance of the films is above 85% in the visible range.The absorption edge initially blue-shifts and then red-shifts with the increase of Na doping content.The optical constants of these films were calculated using transmission spectra.Refractive indices of the films in the visible range decrease at first and then increase with increasing Na doping content.

Degradation of Antibiotics in Aqueous Solution by Photocatalytic Process： Comparing the Efficiency in the Use of ZnO or TiO2

The study examined the photodegradative efficiency of ZnO and TiO2 in degradation of antibiotics in aqueous matrices. Among several types of antibiotics, four antibiotics were chosen to feature the major classes of these compounds： amoxicillin, erythromycin, streptomycin and ciprofloxacin. Degradation of antibiotic solutions was carried out mainly under UV-light irradiation in a set time with the presence of small quantity of zinc oxide or titanium dioxide. Solutions were analyzed with HPLC chromatography and degradation percentages were calculated from ratio between pick area associated to no degraded drug solution and degraded drug solution＇s pick area. Meanwhile, toxicity of antibiotics and degrading compounds were investigated using a biosensor system, consisting of Clark＇s electrode associated with a portion of agar medium culture containing Saccharomyces Cerevisiae yeast cells. This way, it was possible to define the oxygen that was consumed by yeast cells. Toxicity associated to antibiotics and degrading products are related to decrease of oxygen concentration in solution. It is clear that zinc oxide is slower than titanium dioxide to degrade antibiotics, but zinc oxide shows better photodegradation efficiency than titanium dioxide in spite of its small specific superficial area.

Preparation and characterization of zinc oxide nanoparticles

In the present study, the zinc oxide nanoparticles(ZnO NPs) were prepared by using a sol-gel method. The characterization of ZnO NPs, such as particle size, morphology, crystal form, optical properties and p H-responsive behavior, was carried out. The in vitro anti-tumor activity of ZnO NPs was evaluated on PC-3M and 4T1 cell lines. The results indicated that ZnO NPs were spherical NPs with uniform particle size, excellent fluorescence properties, and p H-responsive behavior. The in vitro anti-tumor activity of ZnO NPs was observed on PC-3M and 4T1 cell lines. Considering to above characteristics, Zn O NPs could be used as drug delivery carries for loading active compound performing therapeutic and diagnostic effect.