What is caustic calcined magnesite and how is it produced?
What Is Caustic Calcined Magnesite (CCM)? Caustic calcined magnesite (CCM), also known as light burned magnesia or caustic magnesia, is a highly reactive form of magnesium oxide (MgO) produced by calcining natural magnesite ore (MgCO₃) at relatively low temperatures of 700–1,000 °C. Unlike dead burned or fused magnesia, CCM retains a high specific surface area (15–50 m²/g) and a citric acid reactivity (CIT) of 10–30 seconds, making it the preferred MgO grade for chemical reactions, environmental applications, agriculture, and animal nutrition. At CNMGO (HOLY Magnesium Industry), CCM is a core product line with MgO purity ranging from 60% to 98%, supplying customers in over 50 countries with an annual production capacity of 80,000 metric tons. How Is Caustic Calcined Magnesite Produced? The production of CCM follows a well-established thermal decomposition process. Below are the four main stages: 1. Raw Material Preparation High-grade magnesite ore (MgCO₃ 43% MgO equivalent) is mined, crushed, and screened to uniform particle size. 2. Calcination in Rotary Kiln The crushed magnesite is fed into a rotary kiln and heated to 700–1,000 °C. The thermal decomposition: MgCO₃ + Heat → MgO + CO₂ ↑ 3. Grinding & Classification The calcined product is cooled, ground to target fineness (200–325 mesh for powder, 0.1–2 mm for granular). Magnetic separation removes ferrous impurities. 4. Quality Control & Packing Each batch is tested for MgO content, reactivity (CIT), and LOI. Packed in 25 kg, 50 kg, or 1,000 kg jumbo bags with custom options. Key Properties of CCM at a Glance Calcination Temp 700–1,000 °C Surface Area 15–50 m²/g Reactivity (CIT) 10–30 seconds MgO Purity Range 60% to 98% LOI 2–8% Annual Capacity 80,000 MT Important Considerations When Choosing CCM Reactivity varies by calcination temperature — lower temperature (700–800 °C) produces higher reactivity but lower MgO content. Raw magnesite quality directly affects final product — ores with high SiO₂ or CaO content will produce lower-grade CCM. Storage conditions matter — CCM is hygroscopic. Store in sealed, dry conditions to prevent hydration. Always request a CIT test result before bulk purchasing to ensure reactivity matches your application. Looking for high-quality CCM for your industrial, agricultural, or environmental application? Browse our CCM product range or contact our technical team for a custom specification. Related Questions You May Have What is the difference between light burned magnesia and dead burned magnesia? What are the main applications of CCM in industry? How to test the reactivity of CCM before purchase? Where to buy high purity MgO powder 94-98% in bulk?