How Silicone is Made: Part 1 – From Quartz to Metal Silicon
Understanding materials starts with understanding their origins. Just like with someone you love—you want to know everything about them, right?
In this first article of our “How Silicone is Made” series, we take a deep dive into the raw material that starts it all: metal silicon. From its formation in electric furnaces to its role in producing silicone, this is a story of chemistry, energy, and innovation.
🌋 What Is Metal Silicon?
Metal silicon (also called metallurgical-grade silicon) is a key ingredient in silicone production. It’s produced by reducing silica (SiO₂), which naturally occurs in the form of quartz.
Surprisingly, silicon is the second most abundant element on Earth, just after oxygen:
| Rank | Element | Percentage (%) |
|---|---|---|
| 1 | Oxygen | 49.5% |
| 2 | Silicon | 25.8% |
| 3 | Aluminum | 7.56% |
| 4 | Iron | 4.70% |
| 5 | Calcium | 3.39% |
This abundance is why we’re able to build a huge industry around silicon-based materials.
🔧 How Is Metal Silicon Made?
Here’s a simplified production flow:
Quartz (SiO₂) + Coke → (Electric Furnace @ ~2000°C) → Metal Silicon (98–99.5%) → Crushing → Raw Material for Silicone
Now let’s look deeper into each step involved in producing metal silicon for silicone applications.
🧪 Step-by-Step Manufacturing Process
1. Raw Material Selection
| Material | Description |
|---|---|
| SiO₂ | High-purity quartzite or silica sand with low impurities |
| C | Coke or charcoal with minimal sulfur and phosphorus |
👉 For silicone applications, minimizing impurities like Fe, Al, Ca, and P is crucial.
2. High-Temperature Reduction in Arc Furnace
A sealed or semi-sealed electric arc furnace is used.
Operating temperature: 2000–2500°C
Reduction Reaction (simplified):
SiO₂ + 2C → Si (liquid) + 2CO (gas)
3. Slag Removal and Extraction
Slag (CaO, Al₂O₃, etc.) forms on top and is removed.
Molten silicon is collected from the bottom, cooled, and solidified.
4. Crushing and Sizing
After cooling, silicon is crushed into 1–10 mm chunks or powders.
5. Quality Testing and Analysis
Impurity levels (Fe, Al, Ca, B, P) are checked via ICP and XRF.
For silicone use, Fe and Al should be below a few hundred ppm.
🏭 Metal Silicon Grades for Silicone Use
| Application | Required Purity | Typical Si Content | Notes |
|---|---|---|---|
| Silicone Rubber | ~98.5–99.5% | >98.5% | Low Fe, Al, and Ca are critical |
| Semiconductors | 99.9999%+ (Ultra High) | N/A | Made via chemical vapor deposition (CVD) |
🌎 Global Metal Silicon Production (2023)
According to USGS Mineral Commodity Summaries 2024:
| Rank | Country | Production (kMT) | Notes |
|---|---|---|---|
| 1 | 🇨🇳 China | 5,500–6,000 | 70–80% of global production |
| 2 | 🇧🇷 Brazil | 300–350 | Relies on hydroelectric power |
| 3 | 🇳🇴 Norway | 200–250 | Powered by renewable energy |
| 4 | 🇷🇺 Russia | 100–150 | Major exporter to Europe |
| 5 | 🇺🇸 USA | 70–100 | Balanced between imports and production |
🏢 Leading Producers
Elkem ASA (Norway) – Renowned for sustainable production using hydropower
RIMA Industrial (Brazil) – Brazil’s largest producer using renewable resources
Shin-Etsu Chemical (Japan) – Supplies high-purity metal silicon for silicone
Wacker Chemie AG (Germany) – Major player in silicon and chemical products
Ferroglobe PLC (Spain) – Global presence in silicon materials
📦 Top Importers from China (2024)
From SMM January 2024 report:
| Rank | Country | Imports (kMT) |
|---|---|---|
| 1 | 🇯🇵 Japan | 12.7 |
| 2 | 🇰🇷 South Korea | 5.5 |
| 3 | 🇮🇳 India | 5.4 |
| 4 | 🇳🇱 Netherlands | 5.3 |
| 5 | 🇲🇾 Malaysia | 4.3 |
💰 Price Trends in 2023
Based on IMARC Group data:
| Region | Price (USD/MT, Q4 2023) |
|---|---|
| China | $2,070 |
| USA | $3,570 |
| Europe | $2,510 |
📚 Further Reading
USGS Mineral Commodity Summaries 2024 Index of /pubs/periodicals/mcs2024
Procurement Resource – Silicon Market Trends Silicon Production Cost Analysis Reports 2025
💭 Final Thoughts
From Earth’s crust to your silicone kitchenware or medical-grade rubber—this journey begins with quartz and coke in a blistering furnace. What may seem like a simple gray rock is actually the beginning of a fascinating transformation.
Stay tuned for the next part in our series: “From Metal Silicon to Silicone Compounds”.
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