Transport Processes and Separation Process Principles (Includes Unit Operations) Fourth Edition

12.8. INTRODUCTION AND EQUIPMENT FOR LIQUID–SOLID LEACHING

12.8A. Leaching Processes

1. Introduction

Many biological and inorganic and organic substances occur in a mixture of different components in a solid. In order to separate the desired solute constituent or remove an undesirable solute component from the solid phase, the solid is contacted with a liquid phase. The two phases are in intimate contact and the solute or solutes can diffuse from the solid to the liquid phase, resulting in a separation of the components originally in the solid. This separation process is called liquid–solid leaching or simply leaching. The term extraction is also used to describe this separation process, although it also refers to liquid–liquid extraction. In ...