News
Contact
Address: North of Wutong Avenue, Hi-Tech Park, Jingdezhen City, Jiangxi Province, China
24-Hour Hotline
Enhancing Adsorption in Activated Carbon: The Significance of Iodine Value
Release time:
2025-06-10 16:14
Source:
In the world of activated carbon, the term iodine value often comes up when evaluating product quality. But what exactly does it mean? And how does it relate to the carbon’s real-world performance? In this article, we break down the concept of iodine value in simple terms to help you make informed decisions when choosing activated carbon for your industry.
✅ What Is Iodine Value?
The iodine value is one of the most important indicators of an activated carbon’s adsorption performance. It measures how many milligrams of iodine can be adsorbed by one gram of carbon, typically expressed in mg/g. A higher iodine value generally means a higher capacity to adsorb small molecules, which usually translates into better performance in many purification applications.
✅ Why Is Iodine Value Important?
Iodine molecules are very small, so this test focuses on the micropore structure of activated carbon — that is, pores smaller than 2 nanometers. These micropores are essential for capturing tiny contaminants from water, air, and chemical solutions. A higher iodine value means more micropores, and thus better performance for certain tasks.
For example:
Iodine value of <600 mg/g: Lower adsorption, suitable for general use or pre-treatment.
600–900 mg/g: Moderate performance, used in water and air purification.
900–1100+ mg/g: High performance, ideal for demanding applications like gold recovery, electronics, or pharmaceuticals.
✅ How Is Iodine Value Measured?
Iodine value is typically tested according to standards such as ASTM D4607 or GB/T 12496.8. In a simplified version of the process:
The activated carbon sample is mixed with an iodine solution.
After a set reaction time, the excess iodine is titrated.
The amount of iodine adsorbed by the carbon is calculated.
This test provides insight into how well the carbon can adsorb small, low-molecular-weight compounds.
✅ Common Misunderstandings About Iodine Value
While iodine value is a key indicator, it should not be the only factor considered when evaluating activated carbon. Some common misconceptions include:
“Higher is always better”
Not necessarily. Some applications require mesopores or macropores instead of micropores. A balance is more important.
“Iodine value = overall quality”
Not true. Other important properties include hardness, moisture, ash content, pH, particle size, and surface chemistry.
“Any activated carbon can reach 1000 mg/g”
In reality, iodine value is influenced by raw material, activation process, and intended use. Not all types are meant to have high iodine values.
| Application Field | Recommended Iodine Value | Purpose |
| Gold Extraction | 900–1100+ mg/g | Adsorb dissolved gold ions |
| Water Treatment | 700–1000 mg/g | Remove organic compounds, odor |
| Air Purification | 600–900 mg/g | Trap VOCs and industrial gases |
| Chemical Processing | 800–1100 mg/g | Recover solvents, purify chemicals |
✅ Final Thoughts
Understanding the iodine value of activated carbon helps you choose the right product for your specific application. While it’s a useful indicator of adsorption performance, it should always be evaluated alongside other technical parameters. A well-balanced activated carbon solution—tailored to your industry’s needs—will deliver better results than simply chasing the highest number.
If you’re looking for high-performance activated carbon with reliable iodine values, our technical team is here to help. Contact us today to get expert advice or request a sample.
adsorption performance,iodine value,activated carbon,gold recovery
