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A novel sulfur tolerant water gas shift (SWGS) catalyst has been developed for the applications under lean (low) steam/gas ratio conditions, which has been extensively used for H2/CO adjustment of syngas and H2 enrichment in the world since 2000s with safer operation and lower steam consumption. Technology design and catalyst performances under different lean steam/gas conditions were comprehensively reported. Industrial data were collected from several large scale running plants with a variety of served catalysts characterized and precisely re-examined in the laboratory. It is shown that the developed Mo–Co/alkali/Al2O3 SWGS catalyst can operate very steadily even with the steam/gas ratio as low as 0.2–0.3, and the main deactivation factors are accidental caking, sintering, as well as poisoning impurities, such as As or Cl. The adoption of lean steam/gas SWGS catalyst can significantly improve the plant efficiency & safety and remarkably reduce the actual steam consumption for H2 production, which can decrease CO2 emission correspondingly. The work helps to evaluate how specially designed SWGS catalysts performed under applied lean steam/gas conditions, providing important references for researchers and industry.

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Mg-Zn-Nd master alloys containing spherical quasicrystal phase were prepared under conventional casting conditions. The microstructures and phases of Mg-Zn-Nd ternary alloy have been investigated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The results show that the microstructure of Mg-Zn-Nd master alloys has been changed significantly with the addition of Nd. When adding 5wt% Nd, it is clear that a lot of spherical I-phase with high roundness and size below 10μm distributed evenly in the matrix. With the increase of Nd, the number of spherical I-phases is reduced and rod-like phases increased. The growth process and the final growth morphology of quasicrystal phase are restricted by the element Nd, thus the growth rates of all quasicrystal growth surfaces tend to be consistent, which contributes to the formation of spherical quasicrystal phase.