A model reference adaptive control scheme is designed for the control of both the pH and level variables in a neutralization process in a continuously stirred tank reactor. In this adaptive scheme, the control and parameter estimation laws are derived based on a reference model approach for nonlinearly parametrized systems. By suitably choosing the parameter update and control laws, the algorithms are much simplified for this pH problem. Global stability and zero tracking errors for both pH and level can be achieved with this new adaptive controller. Simulation and comparative results are given to illustrate the control scheme. Experimental results are given for the pH control.