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Possibilities of improving extraction ensuing from the third phase apperance and effect produced by the inert solvent - diluent on the distribution of metals were studied. Results obtained by investigation of numerous extraction systems show that extraction of metals forming chlorometallic acids could be improved by proper choice of solvent composition

Extraction of cobalt(II) and nickel(II) from sulphate solutions with Cyanex 302 diluted in cerosene was investigated. The influence of pH on extraction was examined at two lwvels of metal concentration. Higher distribution ratio for cobalt(II) in the presence of nickel(II) was found at pH 8. For lower metal concentrations and pH 9 for higher metal concentrations. The higher separation factor was recorded at pH 7 for lower metal concentrations (alpha = 1535), becose of very weak extraction of nickel(II). For higher metal concentrations separation factors at pH 8 and 9 were the highest and similar, 173 and 181 respectively. Investigation of the initial Cyanex 302 concentration on extraction was studied too.

During investigation of cobalt(II) and nickel(II) extraction with MOOP in kerosene the third phase was observed under certain conditions. Systems containing cobalt(II) and nickel(II) or both metals were investigated at different initial pH values and initial phase volume ratios under conditions of the third phase formation. Partial distribution ratios and separation factors were calculated.

Ukratko je opisan razvoj i djelovanje Metalurškog i Naftno-petrokemijskog odjela u Sisku Tehnološkog fakulteta Sveučilišta u Zagrebu te kasnije osnovanog Metalurškog fakulteta kao organizacijske jedinice Instituta za metalurgiju, koji djeluje u okviru Metalurškog Kombinata Željezara Sisak. Nastavlja se održavanje visokoškolske nastave metalurgije poštujući kriterije Sveučilišta u Zagrebu jer se Fakultet po osnivanju istovremeno uključuje u sastav Sveučilišta čime po načinu povezivanja sa Sveučilištem i Kombinatom nastaje jedinstvena institucija u zemlji. Prikazana djelatnost ustanove uključuje visokoškolsku nastavu, znanstvenoistraživački i stručni rad, domaću i međunarodnu suradnju, izdavačku djelatnost, organizaciju kontakt studija i drugo. Dan je popis dekana, nositelja čelnih dužnosti, nastavnika i asistenata, udžnbenika i skripata, doktora i magistara znanosti, diplomiranih inženjera i inženjera, studenata koji su primili rektorovu nagradu te bibliografiju (1985.-1999.) nastavnika Metalurškog fakulteta.

Briquetted samples for control analysis by emission spectrometry have to be compact products with smooth surface and good mechanical resistance. To obtain such briquettes the optimal conditions of preparation should be determined for each type of sample (iron ore, sinter, etc.). Two parameters influencing the briquette quality - pressure and pressure time were examined using an originally developed VDM device. The optimal conditions for the preparation of briquetted iron ore and sinter samples were determined.

Examinations of extraction of cobalt(II) and nickel(II) were carried out in prepared (synthetic) samples. On the basis of previous examinations intial pH=8 was chosen as optimal for extraction of cobalt(II) and its separation from nickel(II). Initial concentration of extractant was changed in range of 0.5 to 20 vol. percent, and initial ratio of aqueous phase to the organic phase was 1 and 2. Distribution ratio and separation factor were calculated. The highest distribution ratio of nickel(II) and cobalt(II) was obtained with initial concentration of extractant 15 vol. percent and initial vol. ratio 2.

In this paper the behaviour of boric acid as binder was investigated. On basis of debyegrams and secondary electron micrographs radiolytic changes of boric acid were proved. Debyegrams of sample of boric acid showed that spottiness and prefered orientation were enhanced after exposure of sample to x-Rays. In secondary electron micrographs interruption of regularity of initial lamellar structure after iradiation of boric acid sample coud be seen as broken lamellas and appearance of round-shaped crystals with adhering particles. These radiolytic cahanges have as a result and increased briquetted porosity and are considered to constitute limiting factor for longer use of smples prepared with boric acid as binder.

In an effort to determine the nature of third phase formation, new data concerning the influence of extraction conditions on formation of the tird phase in systems containing diisopropil ether, phosphinic acids or phosphonic esters as extractants are given.

The behaviour of extraction systems containing the diisopropyl ether (IPE) and metals forming chlorometallic acids was investigated in respect to change in metal content. The systems were of the MeCl_3-HCl-H_2O-IPE-S type. The metals (Me) were iron(III) and gallium(III) and the component of the mixed solvent (S) added to IPE were the inert solvent benzene or the acive solvent pentyl alcohol. Under defined conditions change in metal content induced major variations in phase volumes including change in the number of coexisting phases, changes in the concentration of metal and other components in the equilibrated phases and irregular changes of the distribution ratios in the investigated systems.

For better understanding and interpretation of the observed deviation in results of measurement of relative intensity of analytical lines FeK , CaK and SiK in samples of limonite iron ore and sinter mixture specially prepared samples were studied. Limonite iron ores and sinter mixure were ground, separated by sieving into five fractions (size between 200  m and < 50  m), homogenized and formed into briquettes without or with binder. In the same way were prepared samples of mixture of different fractions, mixed in ratios 3 : 1, 1: 1 and 1: 3. All measurements were made on a sequential semiautomatic X-ray spectrometer, diffractometris system and scanning electron probe microanalyser. The results obtained showed that changes in relative intensity were due not only to component participation in each fraction but also to the phase component participation in each fraction but also to the phase composition of grain, its behaviour during the briquetting process, segregation rate and the tendency towards agglomeration and formation of stuck particles.

The influence of heterogeneity on the measurement of relative intensities by the method of X-ray emission spectrometry was studied in prepared model samples. The results obtained enabled the explanation of irregularities observed in the measurement of FeK-alpha, SiK-alpha and CaK-alpha lines in real samples. For the sake of better understanding of the influence of grain size composition mixtures of different sample fractions were studied. Samples of limonite iron ore, sinter, mixture for sinter and blast furnace slag were ground and separated by means of sieves into fractions of different grain size (200-125, 125-90, 90-63, 63-50 and < 50  m). Particular sample fractions in ratios 1:3, 1:1 and 3:1 were mixed, homogenised in a Spex type attachment for homogenisation and formed into briquettes under a pressure of 234 MPa for 1 min. All measurement were made on a diffractometric system and using a sequential semi-automatic Philips X-ray spectrometer. It was found that the results of measurements were influenced by grain size composition but also by grain distribution within briquette and by phase composition.

U radu je prikazan način računanja granice detekcije cerija u nitratno kiselim otopinama na osnovi mjerenja intenziteta CeL*=alpha_1, linije i intenziteta njenog pozadinskog spektra. Između relativno velikog broja faktora koji utječu na osjetljivost u spektrometriji emisije X-zraka, u ovome radu ispitan je utjecaj prirode osnove (koncentracija nitratne kiseline u otopini koja je mijenjana od 1 – 12 moldm^-3) i utjecaj atmosfere spektrometra (vakuum i zrak) na osjetljivost metode određivanja sadržaja cerija u kapljevitim uzorcima. Na osnovi rezultata mjerenja promjena intenziteta CeL*=alpha_1 (do 25%) u kapljevitim uzorcima različite koncentracije HNO_3 u osnovi, dade se zaključiti da osjetljivost primijenjene metode znatno opada sa porastom koncentracije HNO_3, što se može pripisati apsorptivnosti prisutnih iona za CeL*=alpha_1 liniju.

U svrhu određivanja cerija u kapljevitim ekstraktima dobivenim iz nitratno kiselih otopina ispitane su mogućnosti primjene spektrometrije emisije x-zraka. U radu je prikazan način računanja granice detekcije cerija u nitratno kiselim otopinama na osnovi mjerenja intenziteta CeLa1 linije i intenziteta njenog pozadinskog spektra. Ispitan je utjecaj prirode osnove uzorka (koncentracija HNO3 u otopini 1-12 moldm3) i utjecaj atmosfere spektrometra (vakuum i zrak).Osjetljivost primjenjene metode znatno opada sa porastom koncentracije HNO3, što se može pripisati apsorptivnosti prisutnih iona za CeLa1 liniju. Rezultati mjerenja intenziteta CeLa1 linije u zraku i vakuumu (

U kopnenom dijelu krških Dinarida i u bušotinama iz jadranskoga podmorja unutar donjokrednih karbonatnih sedimenata izdvojeno je pet glavnih litofacijesnih jedinica za koje su interpretirani uvjeti i okoliši taloženja. To su: Litofacijes (A) = supratidal s izronjavanjima i kratkotrajnim emerzijama ; Litofacijes (B) = plitki subtidal i intertidal ; Litofacijes (C)= lagune i zatvoreni plićaci ; Litofacijes (D)= plićaci s pokretljivom vodom ; Litofacijes (E) = kasnodijagenetski dolomiti. Korelacija litofacijesa i okoliša taloženja pokazuje da nisu uvijek na svim dijelovima karbonatne platforme u isto vrijeme postojali isti okoliši ili - ako su postojali da nisu egzistirali jednako dugo vremena. Osim toga, na istome su se mjestu na platformi često ponavljali i izmjenjivali isti ili različiti okoliši. To je posljedica različitih obroka tonjenja ili izdizanja pojedinih dijelova karbonatne platforme zbog sinsedimentacijske tektonike, a mnjim dijelom i razlika u obrocima sedimentacije.