Overview
Arbok-Acidion converts the free energy of acid–base neutralization directly into electricity across proprietary bipolar membranes. Acid and alkali are fed to opposite faces of the membrane, protons and hydroxide ions recombine inside the catalytic interlayer, and the resulting ionic current is collected as DC. A 20-ft module delivers 1.2–1.4 MW of continuous output. The stack is reversible: applying current from an external source regenerates acid and alkali from the spent salt solution inside the same hardware, so the working medium is never replaced, only recharged. Reagents are produced internally from desalination brine by bipolar membrane electrodialysis rather than purchased as commodities. The system also runs on external acid and alkaline effluent, in which mode the working medium carries a negative cost through waste gate fees.
Applications
Primary use cases: baseload and dispatchable power at coastal sites with existing desalination; long-duration energy storage where capacity cost matters more than round-trip efficiency; simultaneous neutralization and energy recovery at chemical, metallurgical and mining effluent sites; autonomous power for communities adjacent to acid impoundments and tailings ponds.
Industries and users: desalination operators, chemical and metallurgical plants, mining and phosphate operations, island and off-grid utilities, industrial-ecology operators.
Scale: 1.2–1.4 MW per 20-ft module on internally produced reagent; 0.5–0.9 MW per module on contaminated external streams. Capacity scaled by module count.
Operating Principle
A bipolar membrane joins a cation-exchange and an anion-exchange layer through a thin catalytic interlayer. Under forward operation with acid on the cation-exchange face and alkali on the anion-exchange face, H⁺ + OH⁻ → H₂O proceeds spontaneously inside the membrane, generating 0.82–0.86 V per cell (theoretical 0.828 V from the ionic product of water; ΔG = −79.9 kJ/mol; 22.2 Wh/mol). Cells are assembled into repeating groups combining bipolar, cation-exchange and anion-exchange membranes, each group fed by its own set of flow channels; salt compartments close the internal ionic circuit and terminal electrodes transfer current out. The exact grouping and channel arrangement are proprietary engineering. Under reverse polarity the interlayer dissociates water and reagents re-form from the salt solution, storing energy.
Limitations: bipolar membrane service life under continuous duty is the governing unknown; performance degrades on streams carrying multivalent cations, heavy metals, suspended solids or high organic load; DC output requires inversion.
Key Parameters
Input: acid and alkali at working concentration, produced in-house from desalination brine; or external acid/alkaline effluent. Cell voltage 0.82–0.86 V, close to the theoretical value set by the ionic product of water. Theoretical energy ≈22 Wh per liter of 1 M acid. Practical yield 6–10 kWh per m³ of solution pair. Operating temperature: ambient, with stack cooling keeping conditions well within membrane and electrode thermal limits. Channel flow rate and current density are tuned within the working range demonstrated for bipolar-membrane electrodialysis stacks, balancing throughput against parasitic losses; net specific power reaches the tens of W/m² of bipolar membrane. Module output 1.2–1.4 MW DC. Round-trip efficiency (charge → discharge) 30–55 %. Electrode service life 5–8 years with partial regeneration.
Architecture and Components
Plate-and-frame stacks with fine sub-millimeter flow channels, packed at high density to give a large active membrane surface within a compact container footprint. The stack is divided into independently wired sections, each with its own current collection, arranged to suppress parasitic shunt currents through the electrolyte manifolds by design rather than by throttling flow. Electrodes and current collectors use a proprietary catalytic preparation that avoids noble metals and redox-shuttle mediators such as ferro/ferricyanide. Pumps, piping, buffer vessels, heat exchangers, inverters and controls are external or chassis-mounted, so effectively the whole internal volume of the 20-ft container is generating elements.
Advantages
Technical: fuel-free and weather-independent; reversible — the working medium is regenerated in the same hardware; no combustion, no pressure, no flammable gases, no heavy metals; energy capacity decoupled from power (added duration costs only tank volume); modular scaling by container.
Economic: working-medium cost $0.035–0.08 per kWh against $0.59 per kWh of fuel-only cost for an equivalent diesel generator — a ratio of 7–15; electrode contribution $0.012–0.029 per kWh; on external effluent the working medium carries negative cost through gate fees of $58–230 per tonne.
Environmental: neutralizes acid and alkaline waste streams while generating; no chlorine or hydrogen evolution in the BMED reagent stage, unlike chlor-alkali; closes the brine loop for co-located desalination.
Strategic: charged state holds two commodity chemicals with an independent market price, so the operator can dispatch electricity or ship reagent; membranes, electrode material and reagent cycle are all in-house, removing external supply-chain dependence.
Integrations
Reverse-osmosis and electrodialysis desalination plants (brine feed, CIP reagent supply); bipolar membrane electrodialysis as the charge stage; grid inverters and microgrids; industrial effluent pre-treatment trains (settling, filtration, selective precipitation); soda ash operations as an alternative co-produced reagent source.
Deployment & Operation
Steps: site container and external balance-of-plant → connect brine or effluent feed → commission BMED reagent stage → operate flow-through, discharging on demand and recharging on cheap or surplus power. Operation is continuous with buffer tankage sized to the required duration. Maintenance is sectional — individual stack blocks are replaceable without shutting down the module. Contaminated feeds require pre-treatment and more frequent flushing.
TRL
TRL 5 (confirmed by Michael). Principle proven and parameters confirmed at laboratory scale; industrial module in development. Remaining before deployment: long-duration bipolar membrane lifetime data, verified membrane cost per m², measured losses in aggregating the sectioned stack onto a single DC bus, and field data on real contaminated streams.
Market Potential
Three converging markets. Coastal and island power where desalination already exists and brine disposal is a liability. Long-duration storage, where the decoupling of capacity from power gives a cost-per-hour-of-storage far below lithium and a round-trip efficiency comparable to hydrogen without compression or cryogenics. Industrial ecology, where operators already pay to neutralize acid and alkaline effluent and the energy is currently dissipated as heat.
Typical Project Economics
Reference case, Europe mid-2026, 1.3 MW, 8,000 h/year. Diesel: 0.23 L/kWh → 2.39 million liters and $6.1 million per year on fuel alone, $0.59/kWh. Arbok-Acidion on internally produced acid and alkali, priced at commodity-equivalent rates on a 100 % basis: $0.035–0.08/kWh, $46–105 per hour, $0.35–0.81 million per year. On external effluent: output 0.5–0.9 MW, working medium at negative cost, dual revenue from power sales and $58–230/t gate fees. Module capital cost is dominated by membrane area, and therefore by the in-house cost of producing that membrane — the single largest driver of unit economics.
Risk Factors
Bipolar membrane service life at working concentration and temperature is unproven over long duty and governs both economics and maintenance. Membrane cost per m² has not yet been independently verified by a third party, and it is the main driver of module CAPEX. Aggregating many independent stack sections onto one DC bus is an unsolved-at-scale engineering task whose losses must be measured. Co-ion transport is reported in the literature as 39–65 % of total losses in comparable systems and its magnitude here is unmeasured. Contaminated feeds may poison membranes irreversibly; pre-treatment cost per effluent class is uncharacterized. Because the design is not yet fully patent-protected in every jurisdiction, detailed technical disclosure ahead of filing carries a genuine novelty risk.
Related Technologies
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