Green chemistry advancement in methane storage: a biodegradable surfactant for improved gas hydrate formation and sustainability†

Abstract

This study presents a significant advancement in green chemistry for methane storage through the development of a novel green and safe surfactant, disodium 1-(oleamido monoethanolamine) sulfosuccinate (DSOS), specifically designed to enhance gas hydrate formation. Inspired by the structure of amino acids and SDS, DSOS integrates sulfonate, amide, and carboxyl groups to accelerate methane hydrate nucleation and growth. DSOS outperformed SDS, achieving a final methane uptake of 0.160 mol gas per mol water at 500 ppm, with a conversion degree of 97.03%. DSOS exhibited a dose-dependent effect, with conversion rates of 75.42% at 100 ppm and 83.43% at 300 ppm, highlighting its effectiveness even at lower concentrations. Molecular simulations aligned with experimental findings, confirming DSOS's high effectiveness at low concentrations but reduced performance at higher levels. Structural analysis indicated that while DSOS doesn't change the hydrate growth pattern, it boosts methane solubility and interfacial area, leading to faster hydrate formation. Toxicity assessments demonstrated DSOS's safety, with high cell viability in NIH/3T3 and MRC-5 cells, as well as no significant oral or dermal toxicity. Additionally, DSOS demonstrated 68.9% biodegradation within 28 days using the OECD method, classifying it as readily biodegradable. DSOS proves to be an environmentally friendly and safe surfactant that matches the performance of conventional alternatives like SDS in promoting methane hydrate formation. Its ability to accelerate gas hydrate formation, enhance storage capacity, and perform well in saline and thermally diverse environments positions DSOS as a promising agent for the sustainable development of gas hydrate technologies. This progress represents a significant step toward greener, more efficient methane storage systems, supporting the transition to cleaner energy solutions in the future.