Ion chromatography method development for analysys and water quality control in paper production

[D. Žarković]

PDF/A (176 str.)

Hemija i hemijska tehnologija - kontrola kvaliteta / Chemistry and chemical technology - quality control

Predmet rada ove doktorske disertacije je razvoj i primena jonske hromatografije (eng. Ion-chromatography, IC) za analizu i kontrolu kvaliteta vode u proizvodnji papira. U radu su utvrđeni optimalni uslovi i detaljni postupci za analizu i praćenje sadrţaja jonskih vrsta u vodi (anjona neorganskih soli i organskih kiselina), koji negativno utiču na proizvodnju papira i kvalitet krajnjeg proizvoda. U uvodnim ispitivanjima razvijena je i utvrđena metoda supresivne jonske hromatografije za određivanje anjona neorganskih soli i organskih kiselina u procesnoj i otpadnoj vodi pri proizvodnji papira. Najvaţniji anjoni neorganskih soli (F–, Cl–, NO3–, PO43– i SO42–) i anjoni organskih kiselina (mravlje, sirćetne, mlečne, buterne i glikolne) kvantitativno su određeni u uzorcima procesne i tehnološke vode sistema za proizvodnju papira. Dobijeni rezultati ukazuju na to da primena izabrane kolone (IonPac®-AS14) u izokratskim uslovima sa karbonatnim (za neorganske anjone) i hidroksidnim eluentom (za anjone organskih kiselina), samoregenerišućim anjonskim supresorom (ASRS) i detekcijom metodom supresije provodljivosti predstavlja pouzdanu metodu za razdvajanje i određivanje jona u procesnim vodama industrije papira. Rezultati su pokazali da je metoda jonske hromatografije postupkom direktnog injektiranja velike zapremine uzorka sasvim zadovoljavajuća u pogledu selektivnosti, osetljivosti i preciznosti i da je bila pogodna za određivanje anjona u koncentracijama reda veličine mg/L. Postignuto je dobro razdvajanje jona i visoka preciznost, tačnost i linearnost (korelacioni faktor r>0,991, relativna standardna devijacija RSD<8%). Minimalna granica detekcije, MDL je bila manja od 0,36 mg/L za neorganske anjone, odnosno manja od 10,14 mg/L za anjone organskih kiselina. Ukupna koncentracija ispitivanih anjona u procesnoj vodi bila je manja od 1,2 g/L, što prema dostupnim literaturnim podacima predstavlja kritičnu vrednost pri kojoj dolazi do pojave operativnih problema u sistemima za proizvodnju papira. Imajući u vidu najnovija svetska dostignuća, prvi put je kod nas, u laboratorijskim uslovima, izvršena analiza jonskih vrsta u procesnoj vodi industrije papira. Ostvareni su originalni rezultati u oblasti razvoja metode jonske hromatografije za određivanje neorganskih anjona (Cl–, F–, SO42–, NO3– i PO43–), kao i jona organskih kiselina (mravlje, sirćetne, mlečne, buterne i glikolne). Jonska hromatografija sa jasno utvrđenim analitičkim parametrima predstavlja osetljivu i selektivnu metodu koja daje pouzdan, reproduktivan i brz odgovor. Razvijena IC metoda moţe biti integrisana u moderan sistem savremene analitičke kontrole u laboratorijama i sluţbama hemije pri proizvodnji papira. Ovo se posebno odnosi na praćenje sadrţaja sulfat- i hlorid-jona u procesnoj vodi, koji predstavljaju indikatore korozionih procesa. Praćenje sadrţaja anjona organskih kiselina u procesnoj vodi IC metodom predstavlja pouzdano analitičko sredstvo za predviđanje i kontrolu štetnih pojava pri proizvodnji papira (formiranje biloških naslaga, pojačana mikrobiološka aktivnost, nagomilavanje gasovitih produkata metabolizma mikroorganizama i pojava neprijatnih mirisa). Dobijeni rezultati i predloţeni postupci ukazuju na to da se jedna savremena analitička metoda kao što je jonska hromatografija, moţe efikasno primeniti u proizvodnom procesu kao kontrolni parametar za analizu vode.

This thesis details the development and the usage of an Ion-chromatography (IC) method for the analysis and water quality control in paper production. The method was developed by embedding optimal conditions and detailed procedures fot the analysis and control of ion species content in water (anions of inorganic salts and organic acids), which negatively affect paper production and quality of the final product. In preliminary examinations, supressive ion chromatography method was developed for determination of inorganic salts anions and organic acids anions in process water and wastewater of paper production. The most important anions of inorganic salts (F–, Cl–, NO3–, PO43– i SO42–) and organic acids anions (formic, acetic, lactic, butyric and glycolic acids) were detected and quantified in samples of process water and wastewater in paper production system. Obtained results indicate that the application of selected column (IonPac®-AS14) in isocratic conditions with carbonate eluent (for inorganic anions) and hydroxide eluent (for anions of organic acids), self-regenerated anionic supressor (ASRS) with supressed conductivity as the detection type, presents available method for the separation and quantification of ion species in process water and wastewater from paper production. Obtained results appointed that applied and validated IC method with direct injection of large volume of sample, presents quite satisfied method in means of selectivity, sensibility and precision. This method was suitable for anion detection in mg/L concentration range. Beside, good separation of ions and high precision, accuracy and linearity were accomplished (correlation factor r>0,991, relative standard deviation, RSD<8%). Minimal detection limit, MDL was less than 0,36 mg/L for inorganic anions, and less than 10,14 mg/L for anions of organic acids. Total concentration of all analyzed anions in process waters was less than 1,2 g/L. According to relevant literature data, this value presents the critical value for the occurence of operating problems in paper production systems. Acording to the latest worldwide investigations, first time in local area in laboratory conditions, analysis of ion species in papermaking process water was obtained. Original results were accomplished in developement of the ion chromatography for determination of inorganic anions (Cl–, F–, SO42–, NO3– and PO43– -ions), as well as ions of organic acids – formic, acetic, lactic, butyric and glycolic). Ion chromatography method with clearly defined analytical parameters presents highly sensitive and selective method, which brings assured, reproductive and fast response. Developed and validated IC method might be integrated as modern, up-to-date analytical control system in laboratories and chemistry services in paper mills. This is especially appointed in monitoring of sulfate- and chloride-ions in process water, as well as organic acids anions, because they present indicators of corrosion processes. Monitoring of content of organic acids anions in process water with IC method presents assured analytical tool for the prediction and control of harmful effects during paper production (biological slime forming, increased microbiological activity, deposition of vapour microorganizms metabolism and appearance of unpleasent smells). Obtained results and suggested procedures indicate that developed IC method could be effectively used as up-to-date analytical tool in paper production process as control parameter for water analysis.

jonska hromatografija, kontrola kvaliteta, voda, proizvodnja papira, neorganski anjoni, organske kiseline

ion chromatography, water, quality control, paper production, inorganic anions, organic acids

676:628.3(043.3) ; 543.544.1.061(043.3)

Jonska hromatografija

Proizvodnja papira - Otpadne vode - Kontrola kvaliteta

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