INGRID BUCIŞCANU 1*, STELIAN S. MAIER 1, VIORICA DESELNICU 2 (1)“GH.ASACHI” TECHNICAL UNIVERSITY OF IAŞI, DEPARTMENT OF LEATHER CHEMICAL TECHNOLOGY, O.P. IAŞI 10, CP 2070 IAŞI, 700050, ROMANIA (2)LEATHER AND FOOTWEAR RESEARCH INSTITUTE, 93 ION MINULESCU ST, 74259, BUCHAREST, ROMANIA *CORRESPONDING AUTHOR: IIACOMI@C
This paper is dealing with the obtaining of some pillared smectites (SmP) and with the assessment of their adsorptive affinity for several azoic acid dyes, used for leather and fur dyeing. Three SmPs were obtained by the reaction between a native Na-smectite (Sm) and partially hydrolyzed solutions of: AlCl3 (PAC), FeCl3 (PFC) and Fe2(SO4)3 (PFS). The adsorption capacity of three acid dyes – Acid yellow 166, Acid Red 337 and the Acid Green 73 1:2 Cr-complex, was determined at pH = 5.5, over a 25 ÷ 300 mg/L dye concentration range and adsorbent dosage of 2 g/L. The minimal metal/Sm ratios required for a permanent pillaring effect are: 3 mmol Al/g Sm and 4 mmol Fe/g Sm, respectively. The adsorbents efficiency decreases in the order: Sm-PAC > Sm-PFC > Sm-PFS, while the dyes adsorption capacity decreases as follows: Yellow > Green > Red. The maximum uptake was of 232 mg Yellow dye/g Sm-PAC and the minimal uptake was of 28.35 mg Red dye/g Sm-PFS. The S-shaped experimental adsorption isotherms confirm the SmPs mesoporous solids behaviour.
