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1

Precipitation of heavy metals from industrial wastewater by Desulfovibrio desulfuricans

Kosińska K., Miśkiewicz T.

Environment Protection Engineering

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2012

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Vol. 38, nr 2

51--60

EN

Wastewater from leather tanning, electroplating, organic dye production and non-ferrous metallurgy was treated in a batch anaerobic bioreactor of the total volume of 2.7 dm3 using Desulfovibrio desulfuricans for the removal of Crtotal, Cu(II), Fe(II), Ni(II) and Zn(II) as metal sulfides. Except the tannery effluent, the wastewater samples were supplemented with an appropriate quantity of swine manure in order to enrich them with simple organic compounds and biogenic elements (N and P), and thus upgrade the sulfate reducing activity of D. desulfuricans. The metal removal efficiencies obtained varied from 85.2% to 98.96%.

2

Second phase morphology in the Zn-Ti0.1-Cu0.1 single crystals obtained at different growth rates

Boczkal G.

Archives of Metallurgy and Materials

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2012

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Vol. 57, iss. 2

479-484

EN

The influence of growth rate on a morphology, distribution and crystallographic relationship of the intermetallic phase Zn16Ti in Zn-Ti0.1-Cu0.1 single crystals were investigated. The crystals obtained at rates in range of from 1.8mm/h to 16mm/h were tested. In all cases a strong elongation of the Zn16Ti particles along the [11-20] direction is observed. Moreover, it is found that a lamellar phase existing in the crystals develop in range of the growth rate from 6 to 10 mm/h and grows in the f10-11gplanes. In the case of the growth rate of 16mm/h oval-shaped areas of α phase (solid solution of zinc and 0.1wt.% of copper with trace content of titanium) elongated along [10-10] direction and surrounded by needle shaped precipitations are formed in the structure.

PL

W pracy badano wpływ szybkości wzrostu monokryształów Zn-Ti0.1-Cu0.1 na morfologię, rozkład i zależności krystalograficzne fazy międzymetalicznej Zn16Ti. Do testów użyto kryształów wyhodowanych z prędkościami z zakresu od 1.8mm/h do 16mm/h. We wszystkich przypadkach zaobserwowano istnienie cząstek tylko jednej fazy Zn,sub>16Ti, wydłużonych na kierunku [11-20]. Ponadto stwierdzono, że przy szybkości wzrostu z zakresu 6 do 10mm/h, obserwowana faza międzymetaliczna ma postać płytkowa, preferująca płaszczyzny wzrostu f10-11g. W przypadku szybkości wzrostu 16mm/h zaobserwowano tworzenie się fazy iglastej, która otacza obszary czystej osnowy (roztwór stały cynku z dodatkiem 0.1% miedzi oraz niewielką zawartością tytanu) tworzące owale wydłużone na kierunku [10-10].

3

Adsorption of Copper(II) and Zinc(II) ions by various agricultural by-products. Experimental studies and modelling

Turan N. G., Mesci B.

Environment Protection Engineering

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2011

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Vol. 37, nr 4

143-161

EN

Effective removal of heavy metals from aqueous solutions belongs to the most important issues for many industrialized countries. Removal of copper(II) and zinc(II) ions from leaching solution of industrial waste were studied using hazelnut, almond and walnut shells. Batch adsorption experiments were performed in function of pH, contact time and adsorbent dosage. Adsorption kinetics was investigated using the pseudo-first and pseudo-second order, Elovich equations and intraparticle diffusion models. The results indicate that the second order model best describes adsorption kinetic data and the agricultural by products investigated may be used for removal of copper(II) and zinc(II) ions from leaching solution of industrial waste.

4

ZnO/MgO distributed Bragg reflectors

Huo B., Hu L., Zhang H., Zhao Z., Fu Q., Chen X.

Optica Applicata

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2009

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Vol. 39, nr 1

169--174

EN

ZnO/MgO distributed Bragg reflectors (DBRs) are grown by pulsed laser deposition. DBR samples grown at the same temperature and the same pressure show obvious reflections in transmission spectra. If there is a standing wave in the ZnO layers, it is evident that the full width at half maximum of the ZnO peak in photoluminescence spectra could be decreased when the sample reflects more photons whose wavelength is about 380 nm.

5

Microwave regeneration of activated carbon

Dąbek L.

Environment Protection Engineering

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2007

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Vol. 33, nr 2

107-115

EN

Microwave radiation, being more and more frequently applied in environmental engineering, is used lor regeneration of activated carbon, particularly that saturated with organic substances. This paper is concerned with the use of a microwave field to regenerate a spent activated-carbon- supported catalyst for vinyl acetate synthesis, containing both organic substances and zinc compounds. It has been reported that microwave energy applied directly to a spent catalyst removes some of organic substances from its surface. This results in better leaching of zinc compounds by acid solutions. Compared to repeated leaching performed at boiling points of leach solutions, microwave leaching makes it possible to remove more than 90% of zinc compounds in a shorter period of time, using less energy and smaller amounts of solvents.

PL

Energia mikrofal znajduje obecnie coraz szersze zastosowanie w licznych dziedzinach inżynierii środowiska, w tym również do regeneracji węgli aktywnych, głównie nasyconych substancjami organicznymi. W prezentowanej pracy wykorzystano pole mikrofal do regeneracji węgla aktywnego będącego nośnikiem zużytego katalizatora syntezy octanu winylu, w skład którego wchodzą zarówno substancji organiczne, jak i związki cynku. Wykazano, że w wyniku bezpośredniego działania mikrofal na zużyty katalizator z jego powierzchni zostaje usunięta część substancji organicznych, co istotnie ułatwia wyługowanie związków cynku roztworami kwasów. W tych warunkach, wykorzystując ogrzewanie mikrofalowe na etapie ługowania, usunięto z powierzchni zużytego katalizatora ponad 90% związków cynku w krótszym czasie i przy mniejszym zużyciu energii i rozpuszczalników niż podczas wielokrotnego ługowania w temperaturze wrzenia roztworów.

6

Roughness of amorphous Zn-P thin films

Jarząbek B., Jurusik J., Cisowski J., Nowak M.

Optica Applicata

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2001

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Vol. 31, nr 1

93-101

EN

The effect of thickness variation and the surface roughness of amorphous Zn/sub 32/P/sub 68/ thin films has been investigated by the interference spectroscopy of the optical transmittance and reflectance, as well as by the atomic force microscopy (AFM). The analysis of the optical data allowed determination of the standard deviation of the thin film thickness by taking into account the Gaussian distribution of the change in phase of radiation traversing a thin film. It appears that the value of the standard deviation of the film thickness determined from the optical interference spectroscopy ( sigma /sub w/ approximately=26 nm) is comparable with the value of the mean surface roughness (R/sub a/ approximately=19 nm) evaluated from the AFM studies.