Chemistry

Core reactions, formulas, and process chemistry for green hydrogen production and export

H₂ Process Layer

Green Hydrogen Chemistry Overview

From H₂O to H₂, and from H₂ to exportable carriers

This module explains the main chemical reactions behind hydrogen production, conditioning, storage, and export. It connects the plant design layer with the transport and strategy modules of the platform.

Process Chain

Water Input

Purified water is supplied to the electrolyzer system. Water quality matters, especially for PEM units.

Renewable Electricity

Solar or wind electricity powers electrolysis. This is what makes the hydrogen ‘green’.

Electrolysis

Water molecules split into hydrogen and oxygen. Hydrogen is collected, dried, and prepared for storage or conversion.

Conditioning

Hydrogen may be compressed, liquefied, or converted into ammonia / LOHC depending on the transport pathway.

Export / End Use

Hydrogen or hydrogen-derived carriers are delivered to industrial users, power systems, or export terminals.

Quick Parameters

Electrolyzer feedDeionized water + electricity

Main productHydrogen (H2)

By-productOxygen (O2)

Conversion routeDirect H2 / NH3 / LOHC / LH2

Main loss sourcesElectrolysis inefficiency, compression, liquefaction, cracking

Export relevanceStrong for Central Asia → Europe corridors

Water Electrolysis

Core reaction for green hydrogen production from water using renewable electricity.

Overall: 2H2O(l) → 2H2(g) + O2(g)

Cathode: 2H2O + 2e− → H2 + 2OH−

Anode: 4OH− → O2 + 2H2O + 4e−

• Hydrogen is generated at the cathode.

• Oxygen is released at the anode.

• Electricity demand is the main driver of operating cost.

PEM Electrolysis

Proton Exchange Membrane systems operate with high-purity water and respond fast to variable wind/solar power.

Anode: H2O → 1/2 O2 + 2H+ + 2e−

Cathode: 2H+ + 2e− → H2

Overall: H2O → H2 + 1/2 O2

• Fast dynamic response for renewables.

• High hydrogen purity.

• Typically higher CAPEX than alkaline electrolysis.

Hydrogen Compression

Hydrogen is compressed after production for storage, transport, or downstream synthesis.

H2(g, low P) → H2(g, high P)

No chemical conversion, only pressure increase

• Compression consumes extra energy.

• Important for pipeline injection and tank storage.

• Used before export or synthesis steps.

Ammonia Synthesis

Hydrogen can be converted to ammonia for easier long-distance transport.

N2 + 3H2 ⇌ 2NH3

Haber–Bosch process

High pressure + catalyst + elevated temperature

• Ammonia is easier to store and ship than pure hydrogen.

• Can be exported directly or cracked back to hydrogen.

• Useful for maritime logistics.

Ammonia Cracking

At destination, ammonia may be converted back to hydrogen.

2NH3 → N2 + 3H2

Endothermic decomposition reaction

• Adds reconversion losses.

• Requires heat and catalytic system.

• Important in export cost chain.

LOHC Pathway

Liquid Organic Hydrogen Carriers store hydrogen chemically in a liquid medium.

Carrier + H2 ⇌ Hydrogenated carrier

Hydrogenation / Dehydrogenation cycle

• Convenient liquid handling infrastructure.

• Hydrogen release needs heat.

• Often lower delivery efficiency than direct hydrogen routes.