Quantify the fraction of all process materials that are recovered and recycled. MRI captures the circular economy performance of an entire process — across reagents, solvents, catalysts, and auxiliaries — in a single percentage. Results update live as you type, and every session stays in your browser, never on a server.
The Material Recycle Index (MRI) measures the fraction of all materials used in a chemical process that are successfully recovered and recycled, expressed as a percentage. Unlike the E-factor, which quantifies waste generated, or the Solvent Recycle Index (SRI), which is limited to solvents, MRI provides a holistic, process-wide view of circular material use — capturing reagents, solvents, catalysts, auxiliaries, and workup materials together.
A high MRI reflects a genuinely circular process: materials are not simply used once and discarded, but are recovered, returned to the process, and their embedded energy and cost are preserved. This aligns directly with Green Chemistry Principle 1 (Prevent Waste) and supports the broader goals of industrial circular economy.
| Symbol | Term | Units |
|---|---|---|
| $\text{MRI}$ | Material Recycle Index | % (0–100%); ideal = 100% |
| $m_{\text{recycled}}$ | Total mass of all materials successfully recovered and recycled back into the process or supply chain | g (or kg) |
| $m_{\text{total input}}$ | Total mass of all materials entering the process (reagents, solvents, catalysts, auxiliaries, workup materials) | g (or kg) |
"Recycled" means material that is recovered and returned to use — either back into the same process step, to another step, or to an external supply chain. Material sent to incineration, landfill, or waste water treatment is not recycled. The denominator is the total mass of all materials input to the process, not just the waste. A higher MRI is always better.
| Process type | Typical MRI | Notes |
|---|---|---|
| Highly optimised industrial process | 60–90% | Closed-loop solvent recovery, catalyst regeneration |
| Pharmaceutical API synthesis | 10–40% | Complex workup, limited solvent recovery, single-use reagents |
| Undergraduate teaching lab | 0–15% | Minimal recovery; solvents typically disposed |
| Ideal circular process | 100% | All auxiliary materials recovered; only feedstock atoms consumed |
| Metric | What it measures | Ideal direction |
|---|---|---|
| E-Factor | Mass of all waste per mass of product | Minimise (→ 0) |
| PMI | Total material input per mass of product | Minimise (→ 1) |
| SRI | Fraction of solvents recovered and recycled (%) | Maximise (→ 100%) |
| MRI | Fraction of all materials recovered and recycled (%) | Maximise (→ 100%) |
| WRR | Fraction of generated waste that is recovered/recycled | Maximise (→ 100%) |
Enter all materials used in the process: reagents, solvents, catalysts, and workup/purification materials. For each entry, enter the total mass used and the mass successfully recovered and recycled. The desired product(s) should not be included here — MRI measures the recycling performance of auxiliary and process materials, not product recovery.
| Material name | Category | Mass used (g) | Mass recycled (g) | Recycle % |
|---|
| Material | Category | Mass used (g) | Recycled (g) | Not recycled (g) | Recycle % | Visual |
|---|---|---|---|---|---|---|
| Enter materials above to see breakdown. | ||||||
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