Integrated Membrane Process for the Recovery of Chromium Salts from Tannery Effluents
| Autor: | Leondina Della Pietra, Alfredo Cassano, Enrico Drioli |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Suspended solids
integumentary system Chemistry General Chemical Engineering Leather industry technology industry and agriculture Ultrafiltration chemistry.chemical_element chromium recovery General Chemistry Permeation Pulp and paper industry Tannery effluents Industrial and Manufacturing Engineering Chromium Membrane nanofiltration Scientific method Nanofiltration |
| Zdroj: | Industrial & engineering chemistry research 46 (2007): 6825–6830. doi:10.1021/ie070144n info:cnr-pdr/source/autori:Cassano A.; Della Pietra L.; Drioli E./titolo:Integrated membrane process for the recovery of chromium salts from tannery effluent/doi:10.1021%2Fie070144n/rivista:Industrial & engineering chemistry research/anno:2007/pagina_da:6825/pagina_a:6830/intervallo_pagine:6825–6830/volume:46 |
| ISSN: | 1520-5045 0888-5885 |
| DOI: | 10.1021/ie070144n |
| Popis: | Conventional chrome tanning in leather production produces spent liquors containing significant amounts of chromium and other polluting substances, both organic and inorganic. The aim of this study was to identify a technically viable method for recovering chromium salts from spent tanning liquors. For this purpose, an integrated process based on a preliminary ultrafiltration (UF) treatment of the spent liquor followed by a nanofiltration (NF) treatment of the UF permeate was studied on the laboratory scale. The UF process permitted a marked reduction of suspended solids and fat substances to be obtained. A tanning solution with a chromium(111) concentration of about 10 g/L was obtained in the NF process. The concentrated chromium solutions were used in experimental trials of chrome tannage performed on pickled sheepskins (experimental group). Their properties were compared with those of skins (control group) treated with the conventional method using basic chromium sulfate powder. The NF retentate seems to guarantee improved characteristics of the tanned skins with respect to the control group. Furthermore, a higher percentage of chromium depletion was observed for the tanning operation performed with the NF retentate. The process also permitted the reuse of the NF permeate in the pickling step because of its high content of chlorides. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|