Determination of water samples by electrothermal atomic absoption spectrometry

Şimşek, Nail Engin
Boron (B) is a rare element on Earth crust with a natural abundance of 0.001%. However, boron content of water and soils may be significantly high in the regions with rich boron reserves. In addition, extensive use of agrochemicals in soils as well as various natural processes increases the boron concentration in water. Despite B is an essential element for all living creatures, it may pose risks at high level exposures. World Health Organization (WHO) has recommended a daily intake of 1 to 13 mg B for adults. Turkey has almost 70% of world boron reserves principally in four regions: Kütahya, Emet; Balıkesir, Bigadiç; Eskişehir, Kırka and Bursa, Kemalpaşa. The boron content of water in these regions may go up to significant levels. Therefore, it is important to determine B in drinking water from these regions. Electrothermal atomic absorption spectrometry (ETAAS) is a relatively sensitive technique for determination of boron. However, the technique suffers from formation of molecular boron compounds. Therefore, use of chemical modifiers and pyrolytically coated graphite tubes modified with refractory carbide forming elements (Ta, W, Zr, Pd, Ru, Os) were utilized to develop a reliable and sensitive method. Based on optimization studies, Tantalum (Ta) coated tube and co-injection of 5.0 µL 0.01 mol/L Ca(NO3)2, 5.0 µL 0.05 mol/L citric acid together with 15.0 µL sample solution prepared in 1000 mg/L Mg(NO3)2 have been chosen as optimum conditions. Optimum temperatures for pyrolysis and atomization temperatures were determined as 1100 and 2700 °C, respectively. Under these conditions, a detection limit of 0.088 mg/L and a characteristic mass of 186 pg for 15.0 µL sample volume were obtained. The accuracy of the method was checked by EnviroMAT-Waste Water EU-L-1 CRM and NIST 1573a Tomato Leaves SRM analyses. Drinking water samples were collected from Balıkesir, Bigadiç and Kütahya, Emet and analyzed by the developed method. Samples were also analyzed by more sensitive techniques; ICP-OES and ICP-MS for a comparison study. The results are compatible with each other.


Production of boron nitride by carbothermic and mechanochemical methods, and nanotube formation
Camurlu, HE; Aydogdu, A; Topkaya, Yavuz Ali; Sevinc, N (2003-09-12)
The formation of hexagonal boron nitride by carbothermic reduction of boron oxide and nitridation has been examined. Experiments were conducted in the temperature range of 1100-1500degreesC for durations between 15-240 minutes. Products were examined by X-ray, SEM and chemical analysis. The results showed that the reaction proceeds through a gaseous boron containing species, which is most probably 13203(g). It was found that all of the carbon was consumed and formation of boron nitride was complete in 2 hou...
Investigation of the in vitro cytotoxic effects of boron on human hepatocellular carcinoma cell line, HepG2
Çöpoğlu, Hülya; Güray, Tülin; Aydın Son, Yeşim; Department of Molecular Biology and Genetics (2017)
Boron is a widely available element found in the earth’s crust. It is an essential micronutrient for plants and it is also beneficial for animals. At high concentrations boron is known to have toxic effects on cells, and currently the mechanism of this toxicity is still not documented. Liver, kidney, central nervous system, and gastrointestinal track were the most effected organs. Humans mostly exposure to boron as borates or boric acid. The exposure typically occurs through ingestion of food or water, thro...
Determination of boron in hazelnut (Corylus avellana L.) varieties by inductively coupled plasma optical emission spectrometry and spectrophotometry
Simsek, A; Korkmaz, D; Velioglu, YS; Ataman, Osman Yavuz (2003-11-01)
Boron content of 16 Turkish hazelnut (Corylus avellana L.) cultivars were determined by using inductively coupled plasma optical emission spectrometry (ICP-OES) and Azomethine H. spectrophotometric method. The results varied between 13.8 and 22.2 mg/kg. No significant difference was observed between the results by the two methods (P > 0.05). However, the difference among boron content of hazelnut varieties was found to be significantly important (P<0.01). The highest boron content was in Mincane (20-22.2 mg...
Production of boron nitride using chemical vapor deposition method
Mercan, Özge; Özbelge, Önder; Sezgi, Naime Aslı; Department of Chemical Engineering (2014)
Boron nitride is a promising material with its outstanding characteristics like chemical inertness, large band gap, high oxidation resistance and thermal conductivity. It is also used as ceramic matrix component which transfers external load and deflects matrix cracks. Therefore, it has become a subject matter for many studies. In this study, the process of boron nitride (BN) production from diborane (B2H6) and ammonia (NH3) on tungsten (W) substrate in impinging jet reactor is investigated using chemical v...
Evaluation of the alkali reactivity of cherts from Turkey
Bektas, F.; Topal, Tamer; Göncüoğlu, Mehmet Cemal; TURANLI, LUTFULLAH (2008-06-01)
Chert, which is a crypto and/or microcrystalline sedimentary rock, may lead to alkali-silica reaction in concrete when the conditions are favorable. However, cherts vary in composition and consequently may demonstrate different reaction characteristic. In this study, eight different chert types were investigated. Accelerated mortar bar test, ASTM C 1260, was performed on aggregate blends of limestone and chert. Ten sets of mortar bars with varying amount of cherts, 1 to 100%, were tested for each chert type...
Citation Formats
N. E. Şimşek, “Determination of water samples by electrothermal atomic absoption spectrometry,” M.S. - Master of Science, Middle East Technical University, 2012.