Chapter 6 focuses on optimization commands applicable to chemical engineering, explaining MATLAB functions such as 'fminbnd' for single decision variable optimization, 'fminunc' for multivariate problems, and various approaches for linear and quadratic programming. It provides detailed examples and explains how to utilize genetic algorithms and nonlinear programming to solve complex optimization scenarios. Additionally, the chapter covers multi-objective and semi-infinite optimization problems, illustrating practical applications through MATLAB coding examples.