Adsorpcja barwników z roztworów wodnych na popiołach

Celem niniejszej pracy było określenie efektywności adsorpcji barwników anionowych i kationowych z roztworów wodnych na popiołach pochodzących, z dwóch różnych źródeł: ze spalania osadów ściekowych w Grupowej Oczyszczalni Ścieków "Dębogórze" w Gdyni i ze spalania węgla kamiennego w Olsztyńskiej Elektrowni Ciepłowniczej (OZOS). Jako adsorbaty zastosowane zostały barwniki rozpuszczalne w wodzie: z wytworzeniem barwnego kationu - Basic Green 4 (barwnik zasadowy) oraz z wytworzeniem barwnego anionu - Reactive Black 5 (barwnik helaktynowy winylosulfonylowy.

This study was conducted with water-soluble dyes used as sorbates: with the formation of color cation - Basic Green 4 (basic dye) and with the formation of color anion - Reactive Black 5 (helactine vinyl sulfone dye). Its objective was to investigate possibilities of dyes adsorption from aqueous solutions on ashes. The scope of the study included a comparison of adsorption effective-ness of two dyes originating from the textile industry: Reactive Black 5 (RB5) and Basic Green 4 (BG4) by fly ashes of two different origins: from coal combustion at the Olsztyn Thermal Power Station (OZOS), from combustion of sewage sludge originating from Group Wastewater Treatment Plant "Dębogórze" in Gdynia. Results achieved in the study demonstrated that the effectiveness of the adsorption process was determined by the type of dye and adsorbent as well as by pH value of the aqueous solution. In the case of the anionic dye RB 5, the increase in pH was accompanied by diminishing adsorption effectiveness, whereas an opposite tendency was observed in the case of the cationic dye BG4 when the increase in pH value resulted in enhanced dye removal. The fly ashes applied in the research, both from the Thermal Power Station OZOS and from combustion of activated sludge, were characterized by a high effectiveness of cationic dye removal. In the case of the cationic dye BG 4, the highest adsorption capacity (b) accounting for 500.5 mg/g was achieved on fly ashes from the Thermal Power Station at pH = 9.0. In turn, the effectiveness of anionic dye RB 5 removal on both sorbents was at a similar, considerably lower level (0.6÷4%). In the case of this dye, the highest adsorption capacity (b) reaching 6 mg/g d.m. was achieved on ashes from the sludge at pH 3.0, whereas the lowest one ? 0.1 mg/g d.m. - at pH 9.0 on fly ashes from the Thermal Power Station.