Chemical Oxygen Demand and Color Removal from Textile Wastewater by UV/H2O2 Using Artificial Neural Networks

The growth of pollution in aquatic environments increases every day, causing compounds like pharmaceuticas to be detected in surface waters. Thus, tecniques such as advanced oxidation processes (AOP) have been used to degrade this compounds. In this work, the efficiency of AOP in the degradation of nimesulide and ibuprofen pharmaceuticals was evaluated through chromatographic analysis as well as organic matter through the levels of chemical oxygen demand (COD) and total organic carbon (TOC). It was verified that the photo-Fenton process presented the bests results, degrading 89.70% of nimesulide and 93.35% of ibuprofen. This same process managed to reduce COD by 91.60% and mineralize 90.04% of the TOC. The kinetic study showed a good linear fit (R2=0.993) for the clustered kinetic model, as well as a good fit to the mathematical model of artificial neural networks (ANNs), with a value of R2=1.000 for the MLP4-4-1 BFGS 4567 model. Finally, the toxicity of the solution after treatment was verified against the seeds of Lactuta sativa, Cichorium endívia, Ocimum basilicum and American Hard grain. It was found that the seeds that received the solution before treatment had a lower germination amount than the ones where the post AOP treatment solution was added. Then, the root growth was evaluated, in which a relative toxic effect was observed.

Download Full-text

Treatment of textile industry effluents using orange waste: a proposal to reduce color and chemical oxygen demand

Water Science & Technology ◽

10.2166/wst.2016.298 ◽

2016 ◽

Vol 74 (4) ◽

pp. 994-1004 ◽

Cited By ~ 7

Author(s):

Carlos Eduardo de Farias Silva ◽

Andreza Heloiza da Silva Gonçalves ◽

Ana Karla de Souza Abud

Keyword(s):

Chemical Oxygen Demand ◽

Textile Industry ◽

Adsorption Process ◽

Low Cost ◽

High Surface ◽

High Surface Area ◽

Dye Adsorption ◽

Oxygen Demand ◽

Textile Wastewater ◽

Color Removal

Various agricultural residues have been tested as biosorbents due to their low cost, high surface area, and favorable surface chemistry. In this work, a sweet orange albedo was tested as a biosorbent for treatment of real textile effluents. The orange albedo powder was prepared by drying the residue at 50 °C and milling to 30 mesh, and then used for dye adsorption from a alkaline (pH = 10.71) effluent. The adsorption process was studied in batch experiments at 30 °C by measuring color removal and chemical oxygen demand (COD). The color removal was found not to be significantly altered when the effluent was used in its raw state, while COD increased probably due to albedo degradation. For the effluent diluted to 60% (Veffluent VH2O−1), color and COD removal percentages of approximately 89% were obtained. It was found that pH played a very significant role on the adsorption process, as the treated albedo displayed a relative pHPZC* of 4.61, and the highest dye removal efficiencies were reached at pH lower than 2. The COD was strongly influenced by the effluent dilution. The effectiveness in eliminating color and COD shows that orange albedo can be potentially used as a biosorbent to treat textile wastewater.

Download Full-text