**Author details**

76 Multivariate Analysis in Management, Engineering and the Sciences

**Figure 7.** Graph of the two most influential factors in the process

Taguchi planning was applied to the degradation of effluent organic load. The experimental design showed that further reduction of TOC (%) is related to an increase in pH and ultraviolet intensity. The results obtained were significant for the removal of TOC (%) from polyester resin effluent treated with advanced oxidation processes, and heterogeneous

In our Taguchi orthogonal array the removal-percentage achieved was COT = 39.489%, which corresponds to experimental condition number three. This condition is inclusive of

**11. Conclusions** 

photocatalysis.

The most influential factors in the process show the percentage removal of Total Organic Carbon in Figure 7. An increasing degradation of the organic load is observed on the surface. This is achieved by independent variables: pH and potency of the ultraviolet lamp. The percentage of the increased removal of organic load occurs when there is an increase of the power of the lamp and a decrease of the pH. The greatest percentage reduction of the organic load is equal to 39.489%, whose parameters used in this experimental condition = H2O2 were 182 g, pH = 3, TiO2 = 0.250 g / L and the lamp power of 21 W. The response

variable was significant for the degradation of organic matter in the effluent.

Leandro Valim de Freitas *Petróleo Brasileiro SA (PETROBRAS), Brazil* 

Ana Paula Barbosa Rodrigues de Freitas, Leandro Valim de Freitas, Fernando Augusto Silva Marins, Carla Cristina Almeida Loures and Messias Borges Silva *São Paulo State University (UNESP), Brazil* 

Ana Paula Barbosa Rodrigues de Freitas, Carla Cristina Almeida Loures, Fatima Salman, Hilton Túlio Lima dos Santos and Messias Borges Silva *University of São Paulo (USP), Brazil* 

Gisella Lamas Samanamud *University of Texas at San Antonio (UTSA), USA* 
