Influence of process parameters on properties of the 4a zeolite with X-ray and FT-IR instrumental methods characterization

Abstract

For more than three decades 4A zeolite has been an irreplaceable ingredient of powder detergents, but there is still striving to it’s improvement in order to meet the ever more stringent market and environmental demands.Alumina d.o.o., as one of the world-renowned producers of this zeolite, tends to meet these requirements, and one of the latest examples is the work on the production of zeolite 4A with increased adsorption of surface active substances, and the testing of parameters for the synthesis of such a zeolite as well as its characterization is the subject of this paper. The zeolite synthesis were performed to examine the effect of the Na2O concentration in the reaction system, as well as the crystallization time on thecharacteristics of detergent zeolite, namely:the adsorption of dibutylphthalate (DBP), the mean particle diameter, and the ion exchange capacity. The additional characterization of the samples was performed by XRD and FTIR instrumental methods. It’s shown that the conditions examined have a significant effect on the characteristics of the synthesized powders. In general, at all crystallization times, adsorption of DBP, as well as the mean diameter, increases with the increase in Na2O concentration, while the ion exchange capacity decreases,and it is very important to find the right conditions in which all the parameters will be satisfactory.The influence of the crystallization time is not significantly pronounced when adsorption is concerned, but it is on the other characteristics of zeolite.XRD diffractograms and FT-IR spectroscopy showed the effect of reaction conditions on the crystallinity of the synthesized powders, and the relationship between the crystallinity and other characteristics of 4A zeolite.

Zeolit 4A sada već više od tri decenije nezamenljiv je sastojak praškastih deterdženata, ali se i dalje teži njegovom usavršavanju kako bi se što uspešnije ispunili sve strožiji tržišni i ekološki zahtevi. Kompanija Alumina d.o.o. kao jedan od svetski priznatih proizvođača ovog zeolita teži ispunjavanju tih zahteva. Predmet ovog rada je upravo ispitivanje parametara za sintezu takvog zeolita kao i njegova karakterizacija. Sinteze zeolita izvođene su tako da se ispita uticaj koncentracije Na2O u reakcionom sistemu, kao i vremena kristalizacije na karakteristike deterdžentskog zeolita, i to adsorpciju dibutilftalata (DBP), srednji prečnik čestice (Ds50) i jonoizmenjivački kappacitet (JIK).Dodatna karakterizacija uzoraka izvršena je XRD i FTIR instrumentalnim metodama. Pokazalo se da ispitivani uslovi imaju značajan uticaj na karakteristike sintetisanih prahova. Generalno, pri svim vremenima kristalizacije, adsorpcija DBP raste sa porastom koncentracije Na2O, kao i srednji prečnik, dok JIK opada, te je jako bitno pronaći uslove u kojima će svi parametri biti zadovoljavajući. Uticaj vremena nije značajno izražen kada je adsorpcija u pitanju, ali jeste na ostale karakteristike zeolita. XRD difraktogramii FT-IR spektroskopija pokazali su uticaj reakcionih uslova na kristaliničnost, te vezu između kristaliničnosti i drugih karakteristika 4A zeolita.