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EN
In the studies on the recovery of vanadium from vanadium catalyst extracts, three types of polymer strongly acidic ion exchangers were used. The ion exchange resins differed in terms of granularity and their ion exchange capacity. As a result, breakthrough curves were made for three main components of the test extract, i.e.: ions of vanadium, iron and potassium. On this basis the optimum conditions for the removal of iron ions from the solution were defined and the technological concept of the process in the semi-technical scale was proposed.
EN
The results of the precipitation of calcium carbonate from a waste post-distillation liquid (DS) and a sodium bicarbonate saturated solution – both from the Solvay method – in the presence of urea are presented. The investigation was carried out at 293 K and 343 K. Reagent dosage times of 1, 5, 10, 20 and 30 min, and urea concentrations of 5, 6 and 10 mol/dm3 were applied. The granulometric composition, the values of bulk and packing densities and the absorptiveness sorption of water and paraffin oil from the obtained calcium carbonate were investigated.
EN
The results of the leaching of vanadium(V) from the mixture after potassium metavanadate synthesis from KCl and spent vanadium catalyst in the presence of steam were presented. Spent vanadium catalyst was obtained from the waste storage of a chemical plant producing sulfuric acid(VI) by the contact method. The reaction mixture was leached using different solutions: 1 M Na2CO3, 20% CO(NH2)2, 15% NaOH, 15% KOH, 2 M H2SO4. The effect of time and temperature was studied. The results showed that for reaction mixture leached for 4 h at 303 K in the presence of 15% sodium hydroxide solution at a liquid:solid ratio of 10:1, the extent of leaching of vanadium(V) was 95.43%.
EN
The paper presents the results of the research on the degree of the recovery of vanadium(V) from the used vanadium catalyst with the use of KOH solution. The extraction was performed at 293 - 323 K, for 0.5 to 4 h and the catalysts of the variable grain diameter. The concentration of the extracting solution was varied in the range 5 - 20%. The optimal ratio of solid to liquid phase S/L was determined. Additionally the degree of the recovery of total iron ions was presented.
EN
Investigation was carried out on the optimal conditions of the synthesis of NaVO3 and Cl2 from NaCl and V2O5 in the presence of the atmospheric oxygen. The influence of the excess of NaCl relative to V2O5 was investigated. Also the effect of the quartz sand introduced into the reaction mixture on the yield of the NaVO3 synthesis was determined. The obtained product of synthesis was isolated from the post-reaction mixture.
EN
The research was conducted to determine the influence of the pH of the leaching solutions and hydrogen peroxide addition on the efficiency of the recovery of vanadium, potassium and iron compounds from the used vanadium catalyst from the node of oxidation of sulfur dioxide to sulfur trioxide.
EN
The results of the precipitation of calcium carbonate from waste distillation liquor (DS) from the Solvay method and sodium bicarbonate saturated solution in the presence of urea were presented. The investigation was carried out at 293K. The influence of the time of reagents dosage to the solution of urea on the physicochemical character of obtaining product was studied. The time of reagents dosage: 1, 5, 10, 20, 30 min and the concentration of the urea applied: 0.5, 1, 2 and 4 mol/dm3. The granulometric composition, the values of bulk and packing densities and the absorptiveness sorption of water and paraffin oil of the obtaining calcium carbonate were investigated.
PL
Podjęto badania dotyczące wykorzystania zużytego katalizatora wanadowego do syntezy metawanadanu(V) sodu z NaCl oraz metawanadanu(V) potasu z KCl, prowadzonej przy współudziale tlenu z powietrza.
EN
At 873 K, reactions 4(Na or K)Cl + 2V2O5 (spent catalyst) + O2 = 4(Na or K)VO3 + 2Cl2 gave (Na or K)VO3 in (87% or 26%) yields in 4 hrs, air flow rate 182 cm3/min, and with NaCl used in 15% and KCl in 50% excess over V2O5. The catalyst calcined at 800°C/21 hrs. was free of S oxides. The catalyst particle size fractions 0.090–0.125 and 0.355–0.5 mm were resp. best to get the above max. yields
PL
Metodą izotermicznego nasycania roztworów zbadano wpływ stężenia wodorowęglanu potasu na rozpuszczalność metawanadanu(V) amonu w wodzie w temperaturach 313 i 323 K. Uzyskane wyniki stanowiły podstawę do wykreślenia izoterm rozpuszczalności układu KHCO3– NH4VO3–H2O oraz określenia wpływu temperatury i stężenia NH4VO3 na zmiany gęstości badanych roztworów równowagowych. Prezentowane dane są niezbędne przy opracowaniu niskoodpadowej metody wytwarzania K2CO3 w oparciu o karbonizację wodno-amoniakalnych roztworów KVO3.
EN
The soly. of NH4VO3 in aq. solns. was studied by isothermal satn. technique at 313 and 323 K. Soly. isotherms were detd. in the KHCO3–NH4VO3–H2O system and the d. of equil. solns was examd. in relation to NH4VO3 concn. and temp. The data are essential for developing a low-waste prepn. of K2CO3 by carbonation of aq.-ammoniacal KVO3 solns. Solid phases at equil. were identified by X-ray diffraction / were x-rayed. In satd.KHCO3, NH4VO3 affected only slightly the soly of KHCO3. The KHCO3 salted-in NH4VO3 considerably. As temp. was raised, the solys. of KHCO3 and NH4VO3 rose. The d. of satd. KHCO3 rose to attain max. at the temp.-invariant (eutonic) p., then fell to the ds. corresponding to satd. NH4VO3 solns. At each temp., KHCO3 and NH4VO3 were the solids at equil. with the soln. along the lower and the upper boundaries, resp.
19
Content available remote Otrzymywanie węglanu wapnia o niskiej gęstości utrząsowej
PL
Zaprezentowano wyniki badań otrzymywania węglanu wapnia z odpadowego płynu podestylacyjnego DS oraz nasyconego roztworu wodorowęglanu sodu z wykorzystaniem wodnych roztworów mocznika. Badania prowadzono w temp. 333 K. W otrzymanych próbach węglanu wapnia oznaczano gęstość nasypową i utrząsową, punkt płynięcia oraz rodzaj kryształów.
EN
CaCO3 was pptd. in aq. 0.5–2 M urea by using Solvay’s aq. satd. NaHCO3 and waste distn residue (NH3 recovery step) at 333 K. Bulk and tap ds., flow p., and habitus of CaCO3 were detd. The residue was aq. CaCl2 and NaCl with solids and SO4 as impurities which were removed by clearing and filtration. The NaHCO3 soln. was prepd. from crude NaHCO3 taken from the filtration step. The longer the reactants dosing time, the higher the bulk and tap ds. and the lower the CaCO3 flow p. The higher the urea concn., the lower the tap d. (min. at 606 g/l. in 2 M urea), regardless of the dosing time. Urea made the calcite type to cryst., yet conglomerate was the most frequent habitus type.
PL
Przeprowadzono badania określające możliwość wykorzystania rozcieńczonych roztworów mocznika do odzyskiwania związków wanadu(V) ze zużytego katalizatora wanadowego. Oszacowano wpływ czasu i temperatury na wydajność procesu ługowania.
EN
The spent catalyst, 5.0 g, was treated with 50 ml aq. 20% urea at 295–320 K for 5–120 min and filtered. The filtrate was analyzed for V(V) and the max. recovered concn. was 0.0195 mol V/l. Temp. was a minor factor and time was significant for the first 30 min.
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