Remediation of soil contaminated by toxic rocket fuel components using modified carbon-mineral adsorbing material produced from Shubarkol semi-coke modified with Cu 2+

Abstract

Unsymmetrical dimethylhydrazine (UDMH) is an effective but highly toxic fuel conventionally used as a rocket propellant. Removal of corrosive, poisonous, mutagenic, and carcinogenic UDMH and its derivatives requires high efficiency, abundantly available, and low cost materials. This study develops a new carbon-mineral catalytic adsorbent for the remediation of soils contaminated with toxic rocket fuel components (RFC) and investigates its efficiency. The modified carbon-mineral sorbent (CMS) is obtained from the semi-coke and modified with Cu(NH₄)₂[Cu(C₂O₄)₂]. CMS production process is developed and detoxification efficiency using CMS is tested on soil samples from the areas where RFCs contaminated wrecks of separating stages of carrier rockets (SSCR) crash-land. The structure and physicochemical parameters of CMS, as well as the migration activity of rocket fuel transformation products in the soil at the SSCR impact sites, have been investigated, along with the mechanism and transformation pathways. CMS total pore volume: 0.30 cm³/g, iodine sorption capacity: 45–47 mg/g, and specific surface area: 486–502 m²/g. The obtained CMS demonstrated highest efficiency in the sorption and catalytic decomposition of RFCs at soil-to-sorbent ratio of 5:1 with CuO content up to 21.3 wt% and soil-sorbent contact time of 24 h. The soil detoxification reached is 87–99% for the RFC transformation products concentrations ranging from 0.185 to 5.10 mg/kg. CMS with CuO exhibits high sorption capacity and catalytic activity allowing complete restoration of soil contaminated with UDMH and its derivatives.