title: Production of basic chromium sulfate by using recovered chromium from ashes of thermally treated leather.
abstract: Leather wastes tanned with chromium are generated during the production process of leather, hence the wastes from hand crafted goods and footwear industries are a serious environmental problem. The thermal treatment of leather wastes can be one of the treatment options because the wastes are rich in chromium and can be used as a raw material for sodium chromate production and further to obtain several chromium compounds. The objective of this study was to utilize the chromium from leather wastes via basic chromium sulfate production to be subsequently applied in a hide tanning. The obtained results have shown that this is the first successful attempt to achieve desired base properties of the product. The result was achieved when the following conditions were applied: a molar ratio between sodium sulfite and sodium dichromate equal to 6; reaction time equal to 5 min before addition of sulfuric acid; pH of sodium dichromate solution equal to 2. Summarizing, there is an opportunity to utilize the dangerous wastes and reused them in the production scheme by minimizing or annulling the environmental impact and to attend a sustainable process development concept.
authors.affiliation: Department of Chemical Engineering, Laboratory of Wastes Treatment (LPR), Federal University of Rio Grande do Sul, Luiz Englert str., 90.040-040, Porto Alegre, RS, Brazil. alinedet@enq.ufrgs.br
authors.forename: Aline
authors.initials: A
authors.lastname: Dettmer
authors.forename: Keila Guerra Pacheco
authors.initials: KG
authors.lastname: Nunes
authors.forename: Mariliz
authors.initials: M
authors.lastname: Gutterres
authors.forename: Nilson Romeu
authors.initials: NR
authors.lastname: Marcílio
mesh_terms: D002857:Chromium / Q000737:chemistry / Q000302:isolation & purification*; D017608:Chromium Compounds / Q000138:chemical synthesis*; D003247:Conservation of Natural Resources / Q000379:methods; D004787:Environmental Pollution / Q000517:prevention & control; D017745:Incineration; D007220:Industrial Waste / Q000517:prevention & control*; D013431:Sulfates / Q000138:chemical synthesis*; D013633:Tanning
chemical_list: D017608:Chromium Compounds; D007220:Industrial Waste; D013431:Sulfates; D002857:Chromium; C040874:chromium sulfate