LOI Test for Ceramic Raw Materials: Methods & Analysis

LOI Test for Ceramic Raw Materials: Methods & Analysis

Overview

LOI test is done on all incoming raw materials. It is particularly useful for raw materials other than clay, to understand the percentage of organic materials present in those materials.

The Loss on ignition helps to understand the loss of weight in the raw materials during firing after material is dried. Major part of loss of ignition comes from the chemically combined water in the raw material and the organic content. LIO significantly influences raw material shrinkage and firing properties.

Test Procedure

1. Weigh an empty crucible and record as W1

2. Take 100g of raw material and place it in a drier for one hour

3. Allow the material to cool in the desiccator

4. Weigh the crucible plus dried raw material and record as W2

5. Place the crucible in the kiln for firing

6. After firing, cool the crucible in the desiccator

7. Weigh the crucible with fired raw material and record as W3

LOI Calculation

LOI (%) = [(W2 - W3) / (W2 - W1)] × 100