Characteristic analysis of complex antioxidant enzyme inhibitors to inhibit spontaneous combustion of coal

Experimental and Quantum Chemical Study on the Inhibition Characteristics of Glutathione to Coal Oxidation at Low Temperature

“…The g factor reflects the number of unpaired electrons in the system, and the g factor of coal at normal temperature and pressure is higher than the free electrons of the empty groups ( g e = 2.0023) . As can be seen from Figure , the g factors of the three raw coal samples also increase gradually with increasing temperature, which is due to the increase of the free radicals contributing to the ascend of the unpaired electrons.…”

“…Chemical inhibitors are predominantly antioxidants, which can be divided into free radical scavengers, hydroperoxide decomposers, free radical quenchers, metal chelating agents, and so forth . Their mechanism is to inert reactive free radicals, which can fundamentally inhibit the COLT. ,, Li et al proposed 2,2,6,6-tetramethyl-1-piperidine-noxyl (TEMPO), butylated hydroxytoluene, VC, triphenyl phosphite, edetic acid, and phytic acid as new inhibitors from the perspective of inhibiting chain reactions, which showed that they all have certain inhibiting effects and TEMPO had the best inhibiting effects . Lu et al investigated the inhibiting properties of environment-friendly dl -malic acid on lignite and bituminous coal.…”

Study of Butylated Hydroxytoluene Inhibiting the Coal Oxidation at Low Temperature: Combining Experiments and Quantum Chemical Calculations

“…At room temperature and pressure, the g of lignite is higher than that of free electrons (g e = 2.0023), which is related to the coupling of spin orbits. 43 It can be seen from the results that the g of raw coal gradually increases with the temperature rise, mainly because the formation of chain reactions greatly increases the types of free radicals. At the same temperature, the g of BHT-Coal is less than that of raw coal and decreases with the increase in temperature, indicating that BHT can reduce the types and content of free radicals.…”

Experimental Investigation on Using Chloride/Hydroxide Aerosol to Control Spontaneous Combustion of Lignite in Underground Coal Mines

“…The most common disaster in underground coal mines is the spontaneous combustion of residual coal in goafs. ,, Much residual coal, broken rock blocks, and relatively closely-spaced material in goafs make it difficult to locate any fire source therein. , The main fire-extinguishing technologies used in underground goafs are grouting, sealing, plugging, inert media injection, etc. − Unfortunately, these technologies have excellent mine-fire extinguishing effects only when the mining, ventilation, and geological conditions are relatively simple. Consequently, under complex conditions, management of spontaneous coal combustion remains a challenge. − During fires in goafs with large seam dip angles, inert liquids such as mud colloids are injected; however, these materials are susceptible to flow under gravity and thus cannot remain in a fixed area for long periods, which results in the loss of fire extinguishing material and poor performance. − In addition, injecting a large amount of inert gas into the goaf will reduce the content of O 2 in a limited space. Thus, this fire-extinguishing method relies on a continual supply of N 2 or CO 2 , especially onerous on ventilation management to ensure no air leakage. − Therefore, it is necessary to identify techniques with a more effective ability to extinguish incidences of the spontaneous combustion of coal.…”

“…The results showed that the crossing-point temperature increased, index gas concentrations (CO and C 2 H 4 ) decreased, and the activation energy increased with increasing temperature during the coal oxidation. Xi et al proposed the use of a complex antioxidant enzyme inhibitor (SC), which mainly includes polyethylene glycol–Cu, Zn superoxide dismutase (PEG-SOD), Mn catalase (CAT), and sodium dodecyl sulfate (SDS). The SC could not only quickly neutralize superoxide radicals by a disproportionation reaction, but the fused PEG colloid could cover the coal surface to prevent oxygen adsorption and homolysis of chemical bonds, resulting in chain propagation reactions being terminated and generation of new radicals being interrupted.…”