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1.
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2.
Sugar beet molasses vinasse is a by‐product of ethanol fermentation from sugar beet molasses. Its dark brown colour, which is attributable to the presence of caramels, melanoidins and invert alkaline degradation products, cannot be removed by biological methods. The novelty of this work lies in the use of conventional strongly alkaline ion‐exchange resins for the decolourisation of sugar beet molasses vinasse. The aim of the study was to determine the efficiency of two strong‐base ion‐exchange resins, Dowex 2 and Wofatit ES, when used for the decolourisation of sugar beet molasses vinasse. Optimal conditions and extent of decolourisation were related to the concentration and pH of the vinasse, the time of reaction with the resin, and also to the dose and type of the resin used. The greatest extent of decolourisation (92%) was achieved with Wofatit ES dosed in the amount of 5 g/100 mL of 25% vinasse with an initial pH of 10. The optimal time of reaction with the resin indispensable for attaining the maximal effect of decolourisation was 1.5 h for both resins. The highest extent of reduction in chemical oxygen demand (43%) during decolourisation of 25% vinasse (pH 10) was obtained with Dowex 2.  相似文献   

3.
On a bench scale the treatment of electroplating effluents (ZnCl2, NiCl2, NH4Cl, NH3 and two polyether compounds) with Wofatit CA20 is investigated. If the capacity of the resin is utilized to a high degree for the heavy metal ions, the organic matter remains in the filtrate. The results are discussed with regard to the recovery and waste-disposal technology on a large scale.  相似文献   

4.
Wofatit Y 77 is presented as a novel non-ionogenic hydrophilic adsorbing polymer having a large specific BET surface (800 … 1500 m2/g) and a narrow pore size distribution. By the example of selected aromatic compounds with different molar masses it is shown on the basis of the adsorption of individual substances that the adsorption capacity primarily depends on the molecular size and not on the specific inner surface of the adsorber polymer. Favourable possibilities are derived from that for.  相似文献   

5.
After treatment of the anion exchanger resins from several manufacturers with FeCl3 or CuSO4 their capacity to take up thiocyanate ions increases by the factor 2 … 3. By regeneration with diluted sulphuric acid or hydrochloric acid after precipitation of the ferric or cupric hydroxide a thiocyanate solution of 10 and 15 g/l, respectively, is obtained, which can be reused. The hydroxides dissolved in acid are used for the treatment of the ion exchanger. The process is proposed for the regenerating of wastewaters containing thiocyanate.  相似文献   

6.
Four fluorotensides which are used mainly industrially are investigated with respect to their removability from waters. Since, in general, fluorotensides are difficult to remove or not at all removable biochemically, the effects of chemical or physicochemical treatment processes are tested. As the results represented in pictures and tables show, different modes of behaviour can be recognized with respect to the respective purification effect for the investigated fluorotensides, partly among them. Flocculation with Al- and Fe-salts as well as chlorination and ozonization show only partial effects. But all the investigated fluorotensides can be adsorptively eliminated by means of powder or granular active charcoal and adsorbent resin Wofatit EA60.  相似文献   

7.
In this study, a new solid‐phase extraction procedure has been developed for preconcentration and determination of Co ions in different water samples by flame atomic absorption spectrometry (FAAS). Cobalt was preconcentrated as N,N′‐bis(pyridine‐2‐yl‐methyl)benzene‐1,4‐diamine (Co‐BPMBDA) from sample solutions using a column containing Amberlite XAD‐7 and was determined. In order to achieve the best performance for the method, effects of several parameters such as pH, concentrations of ligand, sample flow rate, eluent, and matrix ions on the method efficiency were investigated. Under optimum conditions, the preconcentration factor was found to be 200 for 1000 mL waters samples. Detection limit based on the 3Sb criterion was calculated as 0.24 µg/L for 100 mL of sample solution and relative standard deviation was found to be 1.8%. The method was applied to determine the trace amounts of cobalt in water samples.  相似文献   

8.
The adsorption of fluoxetine onto activated carbons (ACs) prepared from almond tree pruning by steam and CO2 activation under different temperature conditions (650–950°C), was studied. In both series increasing the temperature caused an increase in the BET apparent surface area, yielding ACs with SBET up to 870 and 710 m2 g?1 after steam and CO2 activation, respectively. Also, a slight widening of the porosity was found in both cases. In order to modify the functionality of the ACs, two of them were impregnated with triethylenediamine (TEDA) prior to the adsorption process, which caused a decrease in the AC apparent surface mainly due to micropore blockage. The fluoxetine adsorption isotherms at 25°C showed maximum adsorption capacities between 110 and 224 mg g?1. The adsorption isotherms were analyzed using Langmuir and Freundlich models. Although the impregnation reduced the pore volume, it did not cause a decrease in the fluoxetine maximum adsorption capacity, but a modification in the adsorption mechanism was observed.  相似文献   

9.
Zusammenfassung Es wird der Humins?uregehalt eines von mehreren Gr?ben entw?sserten Verlandungshochmoors untersucht und eine Methode zur Bestimmung der Humins?uren im Wasser ausgearbeitet. Das Prinzip der Methode besteht darin, dass die Humins?uren mit einem Spezialharz (Wofatit E) von nichthuminoiden Begleitstoffen abgetrennt werden und der Kaliumpermanganatverbrauch (PV) des Untersuchungswassers auf diese Weise in zwei Bestandteile aufgegliedert wird. Der den Humins?uren zugeh?rige Anteil des Kaliumpermanganatverbrauchs (PV1) entspricht der Differenz aus dem Gesamt-PV und dem PV nichthuminoider Belgeitstoffe (PV?). Durch Multiplikation von PV1 mit dem Umrechnungsfaktork HS wird der Humins?uregehalt des Untersuchungswassers in Milligramm Humins?ure pro 1 erhalten. Ergebnisse der im Juni 1962 in der Mathematisch-Naturwissenschaftlichen Fakult?t der Martin-Luther-Universit?t Halle-Wittenberg vorgelegten gleichnamigen Dissertationsarbeit. 1. Mitteilung: Schweiz. Z. Hydrol.25 (1963), 9.  相似文献   

10.
The method described uses the separation of As(III) and As(V) species in aqueous samples by means of the anion‐exchange resin Amberlite IRA‐93. The samples were acidified using acetic acid and passed through a glass column filled with pre‐treated Amberlite IRA‐93 resin. As(III) was poorly adsorbed on the anionic exchanger material, whereas As(V) was retained. The arsenic concentration was measured in the column effluent by graphite furnace AAS (GF‐AAS). The retained As(V) was eluted from the column using 1 M NaOH. Prior to the determination of the As(V) concentration in the NaOH eluate, the eluate was passed through a glass column filled with a cation‐exchange resin (Amberlite 200) to remove sodium ions and minimize the Na+ interference with the AAS determination. After calibration the method was applied to the separation of As(III) and As(V) species in two aqueous extracts of arsenic contaminated soils. The results were compared with those obtained from an on‐line separation and determination of As(III) and As(V) in the aqueous soil extracts using a state of the art HPLC‐ICP‐MS system.  相似文献   

11.
The adsorption kinetics of carbamazepine, naproxen, and trimethoprim in aqueous solution by Amberlite? XAD‐7 has been studied. The influence of adsorbent dose (1–3 g/L), stirring rate (80–240 rpm), pH (2–9), temperature (20–60°C), and initial concentration (25–75 ppm) on the adsorption kinetics has been analyzed. The removal efficiency in the first 2 h reaches 85% for carbamazepine, 60% for naproxen, and 70% for trimethoprim. pH appears to be the most important factor conditioning the removal of these latter solutes, whereas carbamazepine adsorption seems to be independent of the pH of the adsorptive solution. Initial concentration and operation temperature moderately influence the adsorption process. Finally, stirring rate scarcely affects the process. The experimental data have been fitted to four kinetic models, namely pseudo‐first and pseudo‐second order, intra‐particle diffusion and Bangham's. The model providing the best fit is the pseudo‐second order one. Again, pH is the factor that affects the adsorption rate in a more remarkable manner although other parameters such as temperature and stirring rate also contribute to accelerate the removal of the solutes. Under the optimal operation conditions, Amberlite? XAD‐7 exhibits a promising ability for the removal of the pharmaceuticals under study.  相似文献   

12.
After extensive experiments aimed at determining the free volatile fatty acids (C2 to C6) in organically highly polluted percolation water of household refuse dumping places there proved optimum a column packed with 10% Carbowax 20 M on Chromatron N-AW-DMCS after having been conditioned for five days at 270°C and subsequently covered with 10% hard wax. On short retention times the investigated isomeric column pairs are completely separated. Equally favourable results were obtained also for liquid manure and silage extracts. The detection limits lie between 10 and 20 mg/l, the relative standard deviation is 20 … 30% in the range of the lower detection limit and 2 … 3% at 200 mg/l in the upper range. In the investigation of percolation waters with concentrations between 235 and 4300 mg/l reproducibility lies at a mean relative standard deviation of 0.5 … 2.8%. The technique is well suited for routine checking.  相似文献   

13.
Investigating adsorption of methyl parathion on the activated carbons Filtrasorb 400 and F 44 and on the adsorption polymer Wofatit Y 77 we found a stronger adsorption on the carbons at smaller concentration whereas the resin has the larger capacity at higher concentration. Adsorbents were regenerated through hydrolysis of the pesticide at pH = 11.7. The velocity of hydrolysis in the adsorbed state is reduced to a tenth of that in solution. However, a transport resistance in the pores of adsorbents seems to be negligible as may be concluded from the very small measured particle diameter dependence of the velocity constants. In adsorption-regeneration measurements the capacity of the adsorbents stabilized at about 70% of that of the fresh adsorbents.  相似文献   

14.
Sediments produced by landslides are crucial in the sediment yield of a catchment, debris flow forecasting, and related hazard assessment. On a regional scale, however, it is difficult and time consuming to measure the volumes of such sediment. This paper uses a LiDAR‐derived digital terrain model (DTM) taken in 2005 and 2010 (at 2 m resolution) to accurately obtain landslide‐induced sediment volumes that resulted from a single catastrophic typhoon event in a heavily forested mountainous area of Taiwan. The landslides induced by Typhoon Morakot are mapped by comparison of 25 cm resolution aerial photographs taken before and after the typhoon in an 83.6 km2 study area. Each landslide volume is calculated by subtraction of the 2005 DTM from the 2010 DTM, and the scaling relationship between landslide area and its volume are further regressed. The relationship between volume and area are also determined for all the disturbed areas (VL = 0.452AL1.242) and for the crown areas of the landslides (VL = 2.510AL1.206). The uncertainty in estimated volume caused by use of the LiDAR DTMs is discussed, and the error in absolute volume estimation for landslides with an area >105 m2 is within 20%. The volume–area relationship obtained in this study is also validated in 11 small to medium‐sized catchments located outside the study area, and there is good agreement between the calculation from DTMs and the regression formula. By comparison of debris volumes estimated in this study with previous work, it is found that a wider volume variation exists that is directly proportional to the landslide area, especially under a higher scaling exponent. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
A relation is derived for the calculation of unknown selectivity coefficients from unknown values of tertiary reactions and its validity is proved by experimental investigations of the systems H+/Na+/Ca2+, H+/Na+/Co2+ and H+/Na+/Al3+ at the strongly acid cation exchanger Wofatit KPS.  相似文献   

16.
Application of Some Complexing Ion Exchangers for Copper Recovery from Natural Water and Wastewater The rational use of water resources is one of the urgent environmental control problems. These problems can be solved by the treatment of sewage. Removal of different non‐ferrous heavy metal ions from wastewater is of great importance. Besides, the selective complexing ion exchangers are of interest because of their good sorption properties. The present paper is devoted to the study of some complexing resins for copper recovery from natural water and sewage. The following carboxylic resins were studied: the cation exchangers KB‐2T, KB‐4 and the amphoteric ion exchangers ANKB 35, AMF‐2T, and AMF‐2S (manufacturer – “TOKEM” company, Kemerovo, Russia). The exchangers investigated differed from each other both by their functional groups and by their matrix physical structures. The copper recovery from CuCl2‐, CuSO4‐, and Cu(NO3)2‐solutions was studied in batch‐experiments (in presence of NaCl, Na2SO4, and NaNO3). The initial copper concentration in the solutions was 0.0002...0.008 mol/L; pH values were 1.0...5.0. After equilibrium (24 h) the resins were separated from the solution. The copper concentration in the solutions after the sorption was determined by the photometrical method with pyridylazoresorcin (λ = 500 nm). On the basis of the experimental data distribution ratio, the separation factors, equilibrium constants, and stability constants of copper complexes in the exchanger phase were calculated. It was found out in this work that the amphoteric ion exchanger AMF‐2T of macroreticular structure is the most effective for the copper sorption from sewage.  相似文献   

17.
—Giant landslides, like melting glaciers, lead to a redistribution of mass which will have isostatic consequences. Three-dimensional numerical modeling experiments were devised to examine how this mass redistribution affects the isostatic flexural curve. A debris avalanche of 10–40% of pre-slide Oahu is required to account for the 1200–5000 km3 Nuuanu deposit, while only ～ 1% of pre-slide Hawaii Island is necessary to generate the 200–800 km3 Alika I and II avalanche deposits. Trials were run using 25, 30, and 40 km elastic plate thicknesses (T e ). The island uplift resulting from the Nuuanu slide was calculated to be 23 m and 109 m for 10% and 40% volume slides, respectively, both using T e = 25 km. A rebound of 10 m and 49 m was calculated for the same volumes, respectively, using T e = 40 km. A greater amount of uplift is expressed direct lyover the failed flank, causing the edifice to tilt away from the calved-off portion. The landslide deposit depresses the plate several meters beneath the debris field itself. Smaller slides (e.g., Alika I and II) do not produce as much flexural response, with 17 m and 7 m uplift for T e = 25 and 40 km, respectively. The effects of slow moving, intact slumps where the failed blocks remain relatively close to the island pedestal were examined for the case of the Hilina slump, making up approximately 10% of the Hawaii Island edifice. Perhaps more significant than the uplift for the Hilina slump, comparable to that for the 10% Nuuanu debris avalanche, is the 114 m and 56 m of downwarp beneath its massive slumped foot (T e = 25 and 40 km, respectively). The landslide rebound process, in the case of a relatively large landslide, should be considered as an added component to the evolutionary course of oceanic islands.  相似文献   

18.
An investigation is made into the performance of a commercial product (Wofatit EP 61) and of newly-developed experimental samples of macroporous adsorption polymers (copolymers of styrene and divinyl benzene) with a much larger specific surface in batch and filter experiments. Against organic adsorptives having the character of weak electrolytes, adsorption polymers show a significantly pH-dependent elimination capacity. Non-ionic or only weakly dissociated anionic adsorptives are removed by the experimental samples to a much higher degree than by the commercial adsorption polymer. Highly dissociated anionic compounds can be removed by activated carbon better than by macroporous adsorption polymers.  相似文献   

19.
The sorption capacity of two natural sorbents of different origin and of Wofatit KPS is determined by dynamic laboratory investigations and the influence of a thermal pretreatment of clinoptilolite, of the type and quantity of regenerants and of the presence of other cations is investigated. There are represented results of the ammonia removal from biologically treated municipal wastewater and of the removal of caesium-ions from laundry wastewaters. The capacity of clinoptilolite is lower than that of the ion-exchange resin, but clinoptilolite has the advantage of a considerably higher affinity for ammonium-ions, so that it can be used also in the presence of other salts in water to be treated. The ammonium concentration should not exceed 30 mg/l, in order to avoid too short filter runs.  相似文献   

20.
The solubility of fluorapatite in a wide variety of basic magmatic liquids was experimentally determined over a range of upper mantle P-T conditions (8–25 kbar, 1275–1350°C). Fluorapatite is stable over the entire range of conditions investigated, but its solubility in melts is variable, depending negatively on SiO2 content of the melt and positively upon temperature, with relatively little sensitivity to pressure above 8 kbar. At upper mantle pressures and a temperature of 1250°C, molten basalt (50% SiO2) will dissolve 3–4 wt.% P2O5 before saturation in apatite is reached. For a magma 100°C cooler or containing 10 wt.% more SiO2, apatite saturation occurs at less than 2 wt.% dissolved P2O5. The observed high solubility of apatite in basic magmas at their normal near-liquidus temperatures virtually precludes the occurrence of residual apatite in mantle source regions. If relatively low-temperature melting conditions prevail (e.g., 1100°C), as might be possible in H2O-bearing regions of the upper mantle, apatite could remain in the residue, but only in amounts too small to have significant effects on the rare earth patterns of the liquids.Because of the high solubility of apatite in basic magmas, phosphorus can be confidently treated as an incompatible element in peridotite melting models. Such models, in combination with observed characteristics of basic lavas, indicate that the upper mantle contains ～200 ppm of phosphorus, much less than the chondritic abundance of ～900 ppm.  相似文献   

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