The chemistry behind water treatment
CIWI offers a smarter way to take control of the chemistry of your water. Powered by steel and salt, our electrochemical technology generates coagulants on-site. Our systems integrate into existing plants with minimal modification. Discover how small adjustments deliver fast, measurable results.
We bind and remove dissolved and suspended pollutants from water using sustainable metal-based additives
01 Pollutants
Pollutants like organic matter, heavy metals such as arsenic, sulphide and phosphate exist in almost every water. If not properly removed, downstream treatment technologies can fail or under perform resulting in failing to meet standards.
02 Coagulation with CIWI
Coagulation makes these pollutants stick together and form larger, suspended, particles that can be removed easily. This is done by adding iron or aluminium, which act like magnets to neutralize the pollutants and clump them together. CIWI provides these treatment agents on-site.
03 Ready to be removed
Once pollutants have clumped together, they can be removed easily by gravity (settling), sand filtration, or membranes. Doing this properly prevents filters and membranes from clogging too quickly, allowing them to clean the water more effectively.
Utilizing electrochemistry, CIWI converts sacrificial steel electrodes into a tailored iron-based coagulant using only water, salt (NaCl), steel, and electricity. In the metal electrolyser, iron is oxidized at the anode (Fe⁰ → Fe²⁺ + 2e⁻), after which Fe²⁺ can be further oxidized to Fe³⁺ depending on redox conditions. The ratio between Fe²⁺ and Fe³⁺, as well as the formation of intermediate hydrolyzed species (e.g. Fe(OH)²⁺, Fe(OH)₂⁺), is actively controlled to optimize coagulation performance.
Simultaneously, a bipolar membrane system splits NaCl into acid (HCl) and base (NaOH), enabling independent control over proton concentration and pH. This allows precise tuning of hydrolysis, polymerization, and speciation of iron, resulting in the in-situ formation of poly-iron hydroxide complexes with enhanced charge neutralization and floc formation properties.
By controlling iron valence, proton availability, and hydrolysis pathways, CIWI produces a reactive, pre-hydrolyzed coagulant—while simultaneously generating NaOH as a valuable by-product—enabling optimized treatment efficiency and reduced chemical footprint.
Smart Chemistry, Real Results
CIWI delivers measurable impact across every level of water treatment operations. From performance and cost savings to sustainability, safety, and supply security, our solution is designed to strengthen plants today while preparing them for tomorrow.
100% equivalent to conventional products, with potential improvements through application-specific, custom-made production.
Operational costs are up to 60% lower than conventional chemicals, with additional upside depending on local chemical prices.
The carbon footprint is reduced by up to 75% from day one. By addressing Scope 3 emissions, we help our partners meet environmental targets.
In many cases, no chemical permits are required due to the low hazard classification. No risk of chemical burns, only mild skin irritation and limited corrosivity to certain metals.
No dependence on chemical prices or availability. Only steel and salt are required, widely available materials, with the flexibility to utilise circular resources such as brine streams.
Enables months of autonomous operation instead of weeks, by eliminating up to 86% of transported mass.
our whitepaper.
In this whitepaper, we explain CIWI's solution in detail: how our technology works, the underlying electrochemical principles, and how we replace traditional chemical supply with on-site production. Discover how we apply "chemistry over chemicals" to make water treatment safer, more efficient, and more sustainable.
information
Molengraaffsingel 12
2629 JD Delft
The Netherlands
