[Ultrasonic Composite Iron-carbon Activated Persulfate for Treating Organic Wastewater].

A coupling system of ultrasonic composite iron-carbon activated persulfate (US/PS/Fe-C) was built to treat a triphenylmethane derivative, crystal violet (CV). The results revealed that US/PS/Fe-C ternary system had a good coupling effect. The structure and surface morphology of commercial Fe-C and self-made Fe-C catalysts were analyzed using an X-ray diffractometer (XRD) and scanning electron microscope (SEM), respectively. Finally, commercial Fe-C was used to study the effects of different factors on the CV of US/PS/Fe-C ternary coupling degradation, and the optimum conditions were as follows:PDS concentration 2 mmol·L-1, iron-carbon catalyst 1 g·L-1, pH without adjustment, and the removal rate of 15 mg·L-1 CV reached 90% after 30 min. To explore the effects of anions and cations on the system, it was observed that Mg2+ and NO3- had almost no effect on the treatment of the system, and Mn2+, Cl-, and CO32- had a certain effect on the treatment of the system, whereas Fe2+ could promote the reaction at low concentration and inhibit the reaction at high concentration. By adding different quenchants, it was concluded that there were four types of active substances:1O2, SO4-·,·O2-, and·OH.

A tuff interlayer in deep potash-bearing salt rocks and its implication for potash mineralization in the Simao Basin, southwestern China.

The lithology and genesis of a dark grey clastic interlayer first encountered within the deepest potassium-rich salt body in the Simao Basin, southwestern China, were analysed. Analyses of the petrography, mineralogy, and element geochemistry of the layer revealed that (1) the layer contains quartz crystals with gulf corrosion edges and explosion cracks and angular volcanic ash-sized glasses; (2) the main mineral components of the crystal fragments are chlorite, illite, biotite, quartz, anhydrite, gypsum, magnesite, pyrite, molybdenite, clinopyroxene, and zircon; (3) the rare earth element patterns, Zr/TiO2 and Nb/Y diagrams as well as boron content all indicate a volcanic origin for the layer. Based on these observations, the layer is suggested to be an altered tuff associated with various volcanic fragments dominated by chlorite and formed after alteration of a parent tuff in an alkaline, salty, and low-temperature water body. Discovery of the layer indicates that the potash-bearing salt rocks could have taken in volcanic materials during these volcanic activities and provides the possibility of reliable zircon U‒Pb dating to determine the absolute age of the host rock, which is fundamental in studying the genetic mechanism of this deeply buried salt body.