Fracturing Fluid Crosslinking via Catalytic Amine

The patent applies preliminary action by pre-forming a complex between the metal ion (Al³⁺ or Fe³⁺) and a ligand (such as EDTA, DTPA, or other chelating agents) before mixing with the hydrocarbon fluid. This pre-complexed metal ion is more reactive and facilitates faster gel formation when contacted with the phosphate ester gelling agent, thereby reducing the mixing time required for onsite applications.

The patent uses an intermediary substance (ligand/chelating agent) that mediates between the metal ion and the phosphate ester gelling agent. The ligand forms a temporary complex with the metal ion that enhances its catalytic activity and reactivity toward the phosphate ester, enabling faster crosslinking and gel formation without requiring direct contact between the metal salt and gelling agent.

The patent applies parameter changes by modifying the chemical composition parameters of the fracturing fluid system. Specifically, it introduces alternative crosslinking mechanisms using metal ions with different coordination chemistries (such as Al³⁺ with octahedral coordination or Fe³⁺ with various ligands) that create more thermally stable crosslinks. This changes the chemical parameters of the gel structure to withstand higher temperatures while maintaining the required viscosity for fracturing operations.

The patent creates a composite crosslinking system by combining multiple components: metal ions (Al³⁺, Fe³⁺), ligands (chelating agents), and phosphate ester gelling agents. This composite approach produces a hybrid crosslinked gel structure where the metal-ligand-phosphate ester complex forms a more thermally stable network than any single component could provide alone, enabling operation at temperatures above 100°C.