Mixing is among the most important unit operation processes in many industries. It involves the mixing of solids, liquids, or gases having two or more than two components.
Mixing is the process where two or more ingredients are treated so that every particle of any one ingredient lies as near as possible to the particle of the other.
Several factors affect the mixing process, like the density of the material, particle size, shape, and proportion of the constituents.
In the pharmacy field, mixing is considered an important process because it might affect the preparation’s efficiency at different steps.
Objective of mixing
Chemical Reaction Enhancement: In chemical industries, mixing is used to continue a reaction appropriately, which requires close contact among reacting substances.
Simple Physical Mixtures: It is a mixture of two or more miscible liquids, homogeneously divided solids, etc., and can be
Physical Changes: They are carried out by mixing such as from supersaturated solution crystals are formed.
Achieving Dispersion: It is also an objective of mixing in which two or more immiscible liquids and one or more liquids with finely divided solids are mixed to produce a quasi-homogenous substance.
To obtain the following types of product, usually the process of mixing operation
True Solutions: These solutions are formed when two or more miscible liquids are mixed.
Emulsions: These are formed when two immiscible liquids are mixed with the addition of an emulsifying agent.
Solutions: These are formed when any solute (solid) is dissolved in a solvent (vehicle).
Suspensions: These are formed when an insoluble solid (solute) is mixed with the solvent or vehicle.
Ointments or Suppositories: These are formed when any liquid or a solid is mixed with a semisolid base.
Capsules: When mixing two or more solid materials, they form a powder, which is then filled into the gelatin capsule shells.
Tablets: When mixing two or more solid substances, they form a powder, which is then compressed under heavy pressure to obtain tablets.
Applications
In tablet and capsule manufacturing, the granulation stage involves actively performing wet mixing.
To facilitate the easy compression of tablets, dry mixing combines various components.
In the manufacturing of capsules, compound powders, and dry syrups, the process involves dry blending of powder.
In capsule manufacturing, the process involves forming pellets.
In tablet manufacturing, the importance of powder mixing lies in the addition of many additives.
Factors Affecting Mixing
Surface Nature
Particle Density
Particle Size
Particle Shape
Particle Charge
Material Proportion
Equipments for Mixing
For the mixing and homogenization process, use a mixer that facilitates random mixing and prevents conditions that may result in segregation. Critically optimize the operational conditions.
Mixing Equipments
· Double cone mixer
· Turbine mixer
· Triple roller mill
· Silverson mixer (homogenizer)
