The Usage of Coated Zeolita for Removing Organic Matter from Compost Water

V diplomskem delu smo proučevali odstranjevanje huminske kisline iz modelnih in kompostnih vod z adsorpcijo na zeolit. Testirali smo štiri različne sintetične zeolite: ZSM-5 Silicalite, ZSM-5 MFI:14-19, ZP-13X, ZP-4A-TSR. Ker se je kot najprimernejši izkazal ZSM-5 Silicalite, smo ga granulirali ter granule oplastili s TiO2. Proučevali smo učinkovitost oplaščenega zeolita in neoplaščenega zeolita za adsorpcijo huminske kisline iz modelne in kompostne vode. Poskuse smo izvajali v koloni z nasutim slojem granul, pri spreminjanju pretoka in pH modelne vode. Pri pretoku 4 mL/min smo na podlagi izmerjenih absorbanc pri 254 nm ugotovili, da je največji izkoristek v kislem pH modelne vode, in sicer za oplaščen zeolit 23,4 % in za neoplaščen zeolit 13,9 %. Pri adsorpciji pod pogoji kislega in bazičnega pH je bil izkoristek adsorpcije višji pri uporabi oplaščenega zeolita napram uporabi neoplaščenega zeolita, ravno obratno pa je bilo pri nevtralnem pH. Pretok smo zmanjšali na 2 mL/min in ponovili poskus z nevtralnim pH modelne vode, pri čemer se je izkazalo, da je izkoristek višji pri uporabi oplaščenega zeolita, in sicer 32,4 % za oplaščen in 26,5 % za neoplaščen zeolit. Poskuse smo na enak način izvedli še s kompostno vodo, pri čemer smo spreminjali pretok. Izkoristek adsorpcije z uporabo oplaščenega proti neoplaščenemu zeolitu v kompostni vodi se je pri pretoku 0,5 mL/min zvišal za 7,0 % in pri pretoku 2 mL/min za 9,9 %.In this thesis we studied the method of removing humic acid from model and compost waters by using zeolite adsorption. Therefore, we tested four different synthetic zeolites: ZSM-5 Silicalite, ZSM-5 MFI:14-19, ZP-13X and ZP-4A-TSR. Since ZSM-5 Silicalite proved to be the most suitable, it was granulated and coated in TiO2. Hence, we proceeded to study the efficiency of the modified and the non-modified zeolites when used for adsorbing humic acid from model and compost waters. The experiments were conducted on a granular column with several alterations to the flow and to the pH of the model water. With the flow rate at 4 mL/min and measured absorbance levels at 254 nm, we concluded that the highest efficiency was in the acidic pH of the model water. Namely, the efficiency of the modified zeolite was at 23,4 %, while the non-modified zeolite tested at 13,9 %. In regards to the adsorption efficiency in the acidic and the basic pH, the modified zeolite proved to be more efficient compared to the non-modified. However, this cannot be said for the neutral pH, where the behaviour proved to be quite the opposite. Namely, the flow was reduced to 2 mL/min and the experiment was conducted once again with a neutral pH model water. The results demonstrated that the efficiency of the modified zeolite was higher, that is at 32,4 %, while the non-modified zeolite tested at 26,5 %. The experiments for compost water were conducted in the same manner, with several alterations to the flow. The adsorption efficiency of the modified zeolite in compost water showed an increase in comparison to the non-modified zeolite. At the flow rate of 0,5 mL/min, there was an increase of 7,0 %, while the flow rate of 2 mL/min raised the efficiency by 9,9 %