Semihydrogenation of acetylene in an ethylene-rich stream is an industrially important process. Conventional supported monometallic Pd catalysts offer high acetylene conversion, but they suffer from very low selectivity to ethylene due to overhydrogenation and the formation of carbonaceous deposits. Herein, a series of Ag alloyed Pd single-atom catalysts, possessing only ppm levels of Pd, supported on silica gel were prepared by a simple incipient wetness coimpregnation method and applied to the selective hydrogenation of acetylene in an ethylene-rich stream under conditions close to the front-end employed by industry. High acetylene conversion and simultaneous selectivity to ethylene was attained over a wide temperature window, surpassing an analogous Au alloyed Pd single-atom system we previously reported. Restructuring of AgPd nanoparticles and electron transfer from Ag to Pd were evidenced by in situ FTIR and in situ XPS as a function of increasing reduction temperature. Microcalorimetry and XANES measurements support both geometric and electronic synergetic effects between the alloyed Pd and Ag. Kinetic studies provide valuable insight into the nature of the active sites within these AgPd/SiO2 catalysts, and hence, they provide evidence for the key factors underpinning the excellent performance of these bimetallic catalysts toward the selective hydrogenation of acetylene under ethylene-rich conditions while minimizing precious metal usage.

A temperature-controlled phase-transfer catalyst-tungsten acid, which in combination with a robust heterogeneous catalyst Ru/C shows a high activity and exceptional reusability for the one-pot conversion of cellulose to ethylene glycol. This binary system can be reused more than 20 times with ethylene glycol yield over 50%.The efficient utilization of biomass for the sustainable production of energy and chemicals is an important way towards both decreasing the dependence on fossil resources and reducing CO 2 emissions. Cellulose is the most abundant biomass on earth, and its non-food nature and rich hydroxyl groups in its molecules make it an ideal feedstock for the production of polyols.

Following our previous report on the selective transformation of cellulose to ethylene glycol (EG) over a binary catalyst composed of tungstic acid and Ru/C, we herein report a new low‐cost but more effective binary catalyst by using Raney nickel in place of Ru/C (Raney Ni+H2WO4). In addition to tungstic acid, other W compounds were also investigated in combination with Raney Ni. The results showed that the EG yield depended on the W compound: H4SiW12O40<H3PW12O40<WO3<H2WO4, but all the investigated W compounds were selective towards EG. Moreover, both WO3 and H2WO4 were dissolved partially under the reaction conditions and transformed into HxWO3, which is the genuinely active species for the CC bond breakage of cellulose. This result further confirmed that the reaction that involves the selective breakage of the CC bonds of cellulose with W species is homogenous. Among various binary catalysts, the combination of Raney Ni and H2WO4 gave the highest yield of EG (65 %), which could be attributed to the high activity of Raney Ni for hydrogenation and its inertness for the further degradation of EG. Moreover, Raney Ni+H2WO4 showed good reusability; it could be reused at least 17 times without any decay in the EG yield, which shows its great potential for industrial applications.