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Investigating the physicochemical properties and embedding forms of residual carbon (RC) and slag particles (SPs) in coal gasification fine slag (FS) is the basis for achieving its separation and utilization. An in-depth understanding of their compositional characteristics allows for targeted treatment and utilization programs for different components. In this work, the physicochemical properties and embedding forms of RC and SPs in FS were systematically investigated. An innovative calculation method is proposed to determine the mass fraction of dispersed carbon particles, dispersed mineral-rich particles, and carbon–ash combined particles by using a high-temperature heating stage coupled with an optical microscope. The unburned RC with a rough, loose surface and a well-developed pore structure acted as a framework in which the smaller spherical SPs with a smooth surface were embedded. In addition, the sieving pretreatment process facilitated the enrichment of the RC. Moreover, the RC content showed significant dependencies according to the FS particle size. For FS with a particle size of 0.075–0.150 mm, the mass proportions of dispersed carbon, ash particles, and the carbon–ash combination were 15.19%, 38.72%, and 46.09%, respectively. These findings provide basic data and reliable technical support for the subsequent carbon and ash separation process and the comprehensive utilization of coal gasification slag. [ABSTRACT FROM AUTHOR]

The ability to rationally design a copper oxide anode with superior rate performance that possesses an ultra-small particle size is highly desirable for lithium-ion batteries (LIBs). Herein, the rapid and effective thermal expansion exfoliation technology was employed to synthesize ultra-small CuOx nanoparticles (∼2.7 nm) uniformly dispersed on graphite oxide after popping (CuOx/Li-PGO), in which the addition of lithium promoted the exfoliation process to obtain an enlarged specific surface area and efficient transfer ability of PGO. The CuOx/Li-PGO electrode achieved a reversible capacity as high as 512.1 mA h g−1 under 2.0 A g−1 after 1000 cycles, demonstrating superior rate performance and cycling stability. [ABSTRACT FROM AUTHOR]

A comprehensive and systematic study on the fundamental pyrolysis behaviors of a single coal particle was performed in this study. The pyrolysis characteristics of coal was investigated by non-isothermal thermo gravimetric analysis whereas the reaction kinetic parameters were obtained by using the distribute activation energy model (DAEM). As three heating rate profiles were applied (10, 20 and 30 °C/min) in TG/DTG experiments with a final pyrolysis temperature of 900 °C, the obtained kinetic parameters, i.e., activation energy (E 0 ), pre-exponential factor (k 0 ) and standard deviation (σ) were 186.5 kJ/mol, 3.96 × 10 10 s −1 and 39.5 kJ/mol, respectively. When these calculated kinetic parameters were used to predict devolatilization curves, the simulation results were in well agreement with the experimental data. As such, a one-dimensional, time-dependent particle pyrolysis model was proposed to characterize the detailed chemical and physical phenomena occurred within a pyrolyzing coal particle. It is found that this model successfully predicted the mass fraction residue and temperature profiles inside the coal particle. In addition, the effect of particle size on pyrolysis performance was also investigated through simulation. It is expected that such a model can be integrated with CFD simulation to provide useful insight for the design of a practical coal pyrolysis reactor. [ABSTRACT FROM AUTHOR]

The ability to rationally design a copper oxide anode with superior rate performance that possesses an ultra-small particle size is highly desirable for lithium-ion batteries (LIBs). Herein, the rapid and effective thermal expansion exfoliation technology was employed to synthesize ultra-small CuO x nanoparticles (∼2.7 nm) uniformly dispersed on graphite oxide after popping (CuO x /Li-PGO), in which the addition of lithium promoted the exfoliation process to obtain an enlarged specific surface area and efficient transfer ability of PGO. The CuO x /Li-PGO electrode achieved a reversible capacity as high as 512.1 mA h g -1 under 2.0 A g -1 after 1000 cycles, demonstrating superior rate performance and cycling stability.

Two sample pretreatment methods were developed and applied to determine 111 residues of pesticides in aquatic products. For Method I, the residues were extracted from homogenized tissue with acetone-ethylacetate-n-hexane (1 : 1 : 1, v/v/v), and then were redissolved in acetonitrile; for Method II, the residues were extracted from homogenized tissue with acetonitrile - water under ultrasonication, and then were separated by liquid-liquid partition. The supernatants were purified using solid phase extraction (Envi-18 and PSA columns) prior to the GC-MS analysis. The determination was performed in selected ion monitoring (SIM) mode with the external calibration for quantitative analysis. Under the optimal conditions, the detection limits (S/N = 3) for residues of pesticides were in the ranges of 0.001 -0.026 mg/kg. The recoveries of Method I for the spiked standards at concentration of 0.25 mg/kg were 72% - 113% with the relative standard deviations (RSDs) of 3.4% - 12.1%. The recoveries of Method II were 51% - 127%, among which the recoveries for 94% pesticides were between 70% and 120% with the RSDs of 3.2% - 13.8%.