Industrial dye degradation
Industrial dye degradation is any of a number of processed by which dyes are broken down, ideally into innocuous products.[1] Many dyes, specifically in the textile industry such as methylene blue or methyl red, are released into ecosystems through water waste.[2] Many of these dyes can be carcinogenic. In paper recycling dyes can be removed from fibres during a deinking stage prior to degradation.
Methods
Heterogeneous photocataylsis is one approach to the degradation of dyes.[3]
As applied to dye-containing effluents from the textile industry, several approaches are standardized for removal or degradation of dyes.[4] These include oxidation, e.g. using air or hydrogen peroxide]], ozone, or Fenton chemistry. One challenge is that oxidants can be indiscriminent such that large amounts of reagents can be required (see Chemical oxygen demand). One promising approach combines oxidation with photocatalysis.[5] Reduction is also employed, a standard reagent being dithionite, which traditionally affords leuco dyes. Precipitation, often coupled with flocculation, is yet another approach, although it can produce substantial quantities of solids.
References
- ^ Rauf, M.A.; Ashraf, S. Salman (2009). "Fundamental principles and application of heterogeneous photocatalytic degradation of dyes in solution". Chemical Engineering Journal. 151 (1–3): 10–18. doi:10.1016/j.cej.2009.02.026.
- ^ Huang, C.; Y. Huang; H. Cheng; Y. Huang. Kinetic Study of an Immobilized Iron Oxide for Catalytic Degradation of Azo Dye Reactive Black B with Catalytic Decomposition of Hydrogen Peroxide. Catalysis Communications 2009, 10 (5), 561-566.
- ^ Pandit, V.K.; Arbuj, S.S.; Pandit, Y.B.; Naik, S.D.; Rane, S.B.; Mulik, U.P.; Gosavic, S.W.; Kale, B.B. Solar Light driven Dye Degradation using novel Organo–Inorganic (6,13-Pentacenequinone/TiO2) Nanocomposite”. RSC Adv. 2015, 5, 10326-10331.
- ^ Sewekow, Ulrich (2016). "Textile Dyeing, 7. Legal Aspects, Toxicology, and Ecology". Ullmann's Encyclopedia of Industrial Chemistry. pp. 1–11. doi:10.1002/14356007.u26_u06. ISBN 9783527306732.
- ^ Shafiq, Iqrash; Hussain, Murid; Shehzad, Nasir; Maafa, Ibrahim M.; Akhter, Parveen; Amjad, Um-e-salma; Shafique, Sumeer; Razzaq, Abdul; Yang, Wenshu; Tahir, Muhammad; Russo, Nunzio (August 2019). "The effect of crystal facets and induced porosity on the performance of monoclinic BiVO4 for the enhanced visible-light driven photocatalytic abatement of methylene blue". Journal of Environmental Chemical Engineering. 7 (4): 103265. doi:10.1016/j.jece.2019.103265. ISSN 2213-3437. S2CID 198742844.