The paper presents results of research on cobalt and nickel ions removal from monocomponent solutions
using Purolite ion exchange resins. It has been shown that C 160 ion exchange resin has the best
sorption properties for both ions (Qe – 72.5 mg Co/g and 88.2 mg Ni/g). Regeneration process of this
ion exchanger has high efficiency, achieving about 93% for cobalt ions and about 84% in case of nickel
ions. It has been shown that the use of ion exchange method with suitable ion exchange resins guarantees
effective removal of cobalt and nickel ions from solutions with very high concentrations corresponding
to contents of these metals in industrial wastewaters (e.g. galvanic). In case of C 160 ion exchange resin,
after the sorption process is carried out in one 50 minute cycle, the cobalt concentration decreased from
about 30 000 mg/L to about 9 500 mg/L (approx. 68%), whereas nickel concentration reached about
6 300 mg/L (approx. 79%). Studied chelating resins don’t have such high sorption capacities. In their
case, it is required to convert cobalt and nickel ions into complex forms. The kinetics of studied processes
were described by pseudo-second order equations.
At present, industrial development is increasing pollution of soils, air and natural waters. These
pollutants have a negative effect on the health and life of living organisms. Metals which interfere with
the natural biological balance and inhibit self-cleaning processes in water bodies have particularly
toxic effects. Cobalt, which gets into the environment from industrial sewage from electrochemical
plants and the metallurgical industry, also belong to this group. This is also relatively rare and precious
element, so it is important to look for additional sources of its recovery. Chemical and physicochemical
methods such as: precipitation, extraction, membrane processes – nanofiltration, reverse
osmosis, sorption and ion exchange are used to recover cobalt. The choice of method depends on: the
kind and composition of wastewaters as well as on form and concentration of the pollutants.
Ion exchange resins produced by Purolite which were used to remove cobalt ions from solutions
with concentrations corresponding to its contents in galvanic wastewater was the subject of the study.
It has been shown that the C 160 ion exchange resin has the best the sorption properties for Co2+ ions
(54.7 mg/g). In case of this ion exchange resin, after sorption process carried out in one 50 minute cycle,
cobalt concentration decreased from about 30 g/L to about 9 g/L. The values of the sorption capacity
do not depend on the method of introducing the solution into an ion exchange column (pouring or dropping).
E ach of the tested ion exchange resins is characterized by a high degree of cobalt concentration
after regeneration using mineral acids, which can be advantageous in selecting the recovery method for
this metal.
In the last decade a growing interest was observed in low-cost adsorbents for heavy metal ions. Clinoptilolite is a mineral sorbent extracted in Poland that is used to remove heavy metal ions from diluted solutions. The experiments in this study were carried out in a laboratory column for multicomponent water solutions of heavy metal ions, i.e. Cu(II), Zn(II) and Ni(II). A mathematical model to calculate the metals' concentration of water solution at the column outlet and the concentration of adsorbed substances in the adsorbent was proposed. It enables determination of breakthrough curves for different process conditions and column dimensions. The model of process dynamics in the column took into account the specificity of sorption described by the Elovich equation (for chemical sorption and ion exchange). Identification of the column dynamics consisted in finding model coefficients β, KE and Deff and comparing the calculated values with experimental data. Searching for coefficients which identify the column operation can involve the use of optimisation methods to find the area of feasible solutions in order to obtain a global extremum. For that purpose our own procedure of genetic algorithm is applied in the study.
In this paper the overview of the recent study on the rare-earth activated waveguides performed in the Optoelectronic Department of IMiO is presented. We reported on the development of rare earth-doped fluorozirconate (ZBLAN) glass fibers that allow a construction of a new family of visible and ultraviolet fiber lasers pumped by upconversion. Especially the performance of holmium devices is presented. The properties of laser planar waveguides obtained by the LPE process and the growth conditions of rare earths doped YAG layers are presented. In this paper we present also the theoretical study of the nonlinear operation of planar waveguide laser, as an example the microdisk Nd:YAG structure is discussed. We derived an approximate formula which relates the small signal gain in the Nd:YAG active medium and the laser characteristics, obtained for whispering-gallery modes and radial modes, to the output power and real parameters of the laser structure
Highly sensitive devices such as the SHRIMP IIe/MC ion microprobe help scientists to make precise measurements of past time-scales, paleoclimatic temperatures, and much more.
The report presents the results of selected heavy metals (Zn, Cu, Cd, Ni, Pb) removal from industrial wastewater sludge collected from metallurgy industry. As washing solutions two chelating agents were used: EDTA and citric acid. The study was focused on 0.000 (deionized water), 0.010, 0.050, 0.075, 0.100 M and 0.000, 0.050, 0.100, 0.500, 1.000 M, EDTA and citric acid solutions, respectively.
Efficiency of EDTA and citric acid solutions for metal removal was studied by extraction of sludge samples with chelators. Chemical extraction of selected metals was effective for both types of solution. Optimal concentration of EDTA was 0.100M for Zn, Ni and Cd, 0.075 M for Cu and Pb. Optimal concentration of citric acid was 0.500 M for all analyzed metals
The adsorption of lead ions onto a zeolite bearing tuff (stilbite) from synthetic acid aqueous solution and
acid mine drainage taken from Sasa mine, Macedonia, is elaborated in this paper. The results present that adsorption
occurs effi ciently in both of cases.
The physical and chemical properties of the used natural material, zeolite bearing tuff, are characterized by X-ray
diffraction, scanning electron microscopy, energy dispersive spectroscopy. The concentration of metal ions in solution
before and after treatment is obtained by AES-ICP.
The effectivity of zeolite bearing tuff is determined through a series of experiments under batch conditions from
single ion solutions, whereby the main parameters are the effects of initial pH of solution, mass of adsorbent, initial
metal concentration in solution, contacting time and competing cations. The maximum capacity of zeolite bearing tuff
for removal of lead ions from solution is determined by equilibrium studies.
The experimental obtained data are fi tted with Freundlich and Langmuir adsorption models. The experimental
data are better fi tted with Langmuir adsorption isotherm.
Zeolite bearing tuff is effective adsorbent for treating acid mine drainage. The results showed that 99% of lead ions
are removed from acid mine drainage, i.e. the concentration of lead ions from 0.329 mg/dm3
decrease to 0.002 mg/dm3
.
The pH value of acid mine drainage from 3.90 after treatment with zeolite bearing tuff increases to 5.36.
Product quality tests require accurate and precise analytical techniques. Fertilizers belong to a group
of products whose chemical composition is of great importance due to health, environmental and economic
reasons. The following paper presents the results of the research into the content of selected substances in several mineral fertilizers manufactured in Poland. Ion chromatography (IC) was employed to determine selected
inorganic anions and cations, whereas energy dispersive X-ray fluorescence spectrometry (EDXRF) was used
to determine the content of selected elements.
In recent years, the increasing threat to ground water quality due to human activities has become a matter of great con-cern. The ground water quality problems present today are caused by contamination and by over exploitation or by combination of both. Reverse osmosis (RO) desalination is one of the main technologies for producing fresh water from sea water and brackish ground water.
Algeria is one of the countries which suffer from the water shortage since many years, so desalination technology becomes inevitable solution to this matter.
In this study, a comparison is provided of results of reverse osmosis desalination for three different qualities of brack-ish water from the central-east region of Algeria (Bouira and Setif Prefectures), wherein they cannot use it as human drink-ing or in irrigation systems. The main objective of our study is to establish a comparison of the reverse osmosis membrane TW30-2540 performances in the term of (permeate flow, recovery rate, permeate total dissolved solids – TDS and salts re-jection) under different operation pressures (each one takes a time of 720 second for pilot scaling). In order to make an overview comparison between the experimental and the simulated results we used ROSA (Reverse Osmosis System Analy-sis) software.
At the end of this study we noted that, the simulated results are lower than the pilot scaling values and the most re-moved salts are the sodium chlorides with 99.05% of rejection rate.
The paper presents an impact of the metallurgical wastes dumping site on the following parts of the environment: air, soil and surface waters. Some of the methods used to prevent wastes interactions were showed. The results of the metallurgical wastes leachate samples research, in which toxic metal ions have been found, are presented results of examinations performed on water extracts derived from two types of metallurgical wastes were given. The chemical analysis of water extracts indicate exceeded concentration of toxic metals, such as: lead, arsenic, barium and others. Preliminary results of some metals elimination from the water extracts with PUROLITE ion-exchangers were also presented. The utilised acidous cationit with Na+ groups exchanges the Ba2+ ions in almost 90%, similar to S 930 ionit with chelating groups (Table 5 and 7). Whereas the anionit with hydroxyl groups removes the arsenic ions(V) from the solution with the 60% efficacy (Table 7).
Analysis is performed of the contemporary views on the effect of ion etching (ion-beam milling and reactive ion etching) on physical properties of HgCdTe and on the mechanisms of the processes responsible for modification of these properties under the etching. Possibilities are discussed that ion etching opens for defect studies in HgCdTe, including detecting electrically neutral tellurium nanocomplexes, determining background donor concentration in the material of various origins, and understanding the mechanism of arsenic incorporation in molecular-beam epitaxy-grown films.