Direct generation of Zn metal using laser-induced ZnS to eradicate carbon emissions from electrolysis Zn production

In response to the goal of net-zero emissions proposed by Intergovernmental Panel on Climate Change, Chinese government has pledged that carbon emissions will peak by 2030, and achieve carbon neutrality by 2060. However, the high carbon energy structure of traditional industries has aggravated environmental problems, such as greenhouse effect and air pollution. The goal of carbon neutrality will be difficult to achieve without the development of disruptive theories and technologies. The electrolytic zinc industry requires high-temperature roasting at ~1000 ℃, generating large amounts of greenhouse gases and SO_(2). High concentrations of sulfuric acid (200 g/L) are subsequently used for electrolysis, and each ton of zinc produced generates 50 kg of anode slime with lead content of up to 16%, as well as 0.35 m3 of wastewater containing zinc and lead. To solve these problems, an optical metallurgy method is proposed in this study. The proposed method uses laser-induced photoreduction to decompose ZnS and reduce metal ions to metal. Results indicate that Zn0 and S8 can be detected on the surface of ZnS at a specific wavelength and laser fluence. The generation mechanism of Zn0 is such that laser induces an electronic transition that breaks ionic bond in ZnS, resulting in its decomposition and photoreduction to Zn0 under an inert argon gas atmosphere. This method does not reduce other metals in the mineral since it does not use high-temperature roasting, providing a new way of producing high-purity metal without greenhouse gas emissions and heavy metal pollution caused by traditional zinc electrolysis.

Rational design of palladium single-atoms and clusters supported on silicoaluminophosphate-31 by a photochemical route for chemoselective hydrodeoxygenation of vanillin

Chemoselective hydrodeoxygenation of vanillin is of great importance in converting biomass into high value-added chemicals.Herein,we describe a facile photochemical route to access palladium single atoms and clusters supported on silicoaluminophosphate-31(SAPO-31)as a highly active,chemoselective,and reusable catalyst for hydrodeoxygenation of vanillin.Characterizations by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy,extended X-ray absorption fine structure measurement,and CO-absorbed diffuse reflectance infrared Fourier transform spectroscopy reveal the atomically dispersed palladium single atoms and clusters are loosely bonded and randomly dispersed,without forming strong palladium-palladium metallic bonding,over the SAPO-31 support.This catalyst,with a full metal availability to the reactants,exhibits exceptional catalytic activity(TOF:3,000 h^(−1),Yield:>99%)in the hydrodeoxygenation of vanillin toward 2-methoxy-4-methylphenol(MMP)under mild conditions(1 atm,80°C,30 min),along with excellent stability,scalability(up to 100-fold),and wide substrate scope.The superior catalytic performance can be attributed to the synergistic effect of the positively charged palladium single atoms and fully exposed clusters,as well as the strong metal-support interactions.This work may offer a new avenue for the design and synthesis of fully exposed metal catalysts with targeted functionalities.

Enantioselectivity of Photochemical Reactions within Polymer Microcapsules

Polymer microcapsule was employed as a reaction medium to achieve enantioselectivity in photochemical reduction of phenyl cyclohexyl ketone and photoelectrocyclization of tropolone methyl ether under the influence of various chiral inductors. In all cases, low but evident enantioselectivity was observed. The poor enantioselectivity is probably due to the facts that not all the capsules include simultaneously both the chiral inductor and the reactant molecules, and the wall of the microcapsule is not rigid enough to hold the reactant and the chiral inductor molecules in close contact.

Dissolved organic matter-mediated reduction of ionic Au(Ⅲ)to elemental Au nanoparticles and their growth to visible granules

The biogeochemical transformation of gold(Au),i.e.its dissolution and re-precipitation,is critical in supergene transport of Au and formation of Au granules.Besides biogenic reduction,the formation Au granules can also be driven by chemical processes.Previous studies have showed the fo rmation of Au nanoparticles(AuNPs)from ionic Au(Ⅲ)can be mediated by dissolved organic matter under sunlight.In this letter,we further demonstrated that these AuNPs can further slowly(in years)grow into visible Au granules.Different sized nano-flower and fractal dendrite-like branched gold structures(from tens of nanometres to over 100μm)were observed in the Au granule sample.This growth of AuNPs into visible Au granules may play a critical role in the supergene mineralization and enrichment of secondary Au and drive the biogeochemical cycle of Au.

Photochemical Synthesis, Properties and X-Ray Crystal Structure of Tetrabutylammonium Dodecamolybdophosphate Heteropoly Blue

The title heteropoly blue, (Bu_4N)_6H_(10)[PMo_(11)~ⅥMo~ⅤO_(40)]_4·H_2Ohas been photochemically synthesized and characterized with elemental analysis, solid diffusionreflectance electronic spectra, CV, ESR, XPS, IR spectra, conductivity measurement and X-ray singlecrystal analysis. The crystallographic data for C_(96)H_(218)Mo_(48)N_6O_(169)P_4 are as follows:M_r = 8889.76, triclinic, P_1, a = 1.4142(3) nm, b = 2.6027(5) nm, c = 2.6403(5) nm, α=113.96(3)°, β = 90.05(3)°, γ= 105.71(3)°, V = 8.481(3) nm^3, Z = 1, D_c = 1.741 g/cm^3, F(000)= 4264, μ= 1.798 mm^(-1). The X-ray crystal structure analysis reveals that there is oneindependent molecule in the unit cell of the title heteropoly blue which contains four mixed-valenceheteropoly anions, six tetrabutylammonium cations and one water molecule. Its molecular structurepossesses a centrosymmetrical arrangement in the unit cell. The phosphorus atom is in thecrystallographic inversion center of the heteropoly anion and the eight oxygen atoms surroundingcentral phosphorus atom comprise of a distorted hexahedron. Heteropoly anion has two equal sets ofPO_4 tetrahedron. The PO_4 tetrahedron and the MoO_6 octahedron in the polyanion are greatlydistorted.