Plan a trial for your application
Industrial wastewater reduction
Measure redox parameters and endpoint residuals in representative site water. Verify the instrument method.
Reductive pulp or textile processing
Compare whiteness, shade and downstream residue on the same substrate within the same operating window.
Purchase specifications and incoming inspection
Include the intended grade or current specification in the enquiry. Use the table to compare selection criteria and inspection conditions. The specification agreed by both parties defines the contractual limits. ENVO public product information · Verify against the ordered grade and lot ↗
| Property | Unit | Published or agreed specification | Test conditions and checks |
|---|---|---|---|
| Active ingredient | Mass fraction | Specify whether expressed as Na₂S₂O₅ or SO₂. | Confirm the reporting basis and use the same method for retesting. |
| Iron | mg/kg | Set an upper limit for the required product color. | Report as elemental Fe and check the method and quantification limit. |
| Insolubles after dissolution | Mass fraction | Set the limit from allowable process residue. | Record water quality, filtration method and elapsed time after opening. |
When approving a sample, record the grade, methods, limits and specification revision. On receipt, match the packing lot number to the lot-specific COA and record the measured values and release decision.
Chemical identity
| Database entry | Molecular or composition formula | Molar mass |
|---|---|---|
| Sodium Pyrosulfite | Na2O5S2 | 190.11 g/mol |
The values refer to the compound indicated. Confirm hydrate form, solution concentration and blend composition for the commercial grade.
From samples to commercial delivery
Packaging and receiving
The public listing specifies PE-lined woven bags. Choose unit net weight with shift demand and moisture-resistant reclosure in mind.
Storage and handling
Keep reducing-capacity results and opening date on receipt. Verify segregation and storage against the applicable SDS.
Sample and order lead times
State the concentration or hydrate, initial net quantity, destination and unloading method. Confirm minimum order, pallet or truckload quantity, dispatch point and arrival date separately.
Questions from the plant
Why does oxidant remain at the same product feed rate?
Measure the target residual before and after treatment in actual influent and retain the feed lot record.
How can metabisulphite and SO₂-equivalent quotations be compared?
Verify actual composition and the conversion used on both reports. Compare the same reducing equivalent and delivered net weight.
Report a delivery or batch issue
Include the order number, lot number from the package, label photos and inspection records for the affected lot. When retesting, check Active ingredient, Iron content, moisture protection after opening.
Request documents for your application
TDS · Technical data sheet
For grade selection and sample approval, specify the grade and revision required.
SDS · Safety data sheet
Specify the country or region of use and the required language.
COA · Certificate of analysis
Request a sample COA during supplier review. For incoming inspection, provide the actual lot number.