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The presence of phosphine (PH3) and hydrogen sulfide (H2S) in industrial tail gas results in the difficulty of secondary utilization. Using waste solid as a wet absorbent to purify the H2S and PH3 is an attractive strategy with the achievement of &ldquo, waste controlled by waste&rdquo, In this study, the reaction mechanism of simultaneously removing H2S and PH3 by modified manganese slag slurry was investigated. Through the acid leaching method for raw manganese slag and the solid&ndash, liquid separation subsequently, the liquid-phase part has a critical influence on removing H2S and PH3. Furthermore, simulation experiments using metal ions for modified manganese slag slurry were carried out to investigate the effect of varied metal ions on the removal of H2S and PH3. The results showed that Cu2+ and Al3+ have a promoting effect on H2S and PH3 conversion. In addition, the Cu2+ has liquid-phase catalytic oxidation for H2S and PH3 through the conversion of Cu(II) to Cu(I).

Nitrate (NO3–) removal on nanoscale zero-valent iron-based nanoparticles (nFe0 particles) represents one efficient and green technology for nitrate pollution abatement, but its development is hindered by the low product selectivity towards harmless N2. Herein we demonstrate the inferior performance of nFe0 in N2 production originates from its over-strong affinity with both the H* and the N-intermediates (denoted as N*), leading to a low N/H molar ratio and a poor mobility of N* on Fe surface that facilitates the formation of NH3 rather than N2. Increasing NO3– feeding concentration or lowing nFe0 dose can uplift the N2 selectivity up to 41.9% (vs. 19.3% by single nFe0 in removing 20 mg L-1 NO3–-N), but has to sacrifice NO3– removal efficiency and yield more toxic NO2–. The nFe0 surface modification by 12.0 wt% palladium (Pd) gives rise to a N2 selectivity of 46.0% and a NO3– removal efficiency above 90% (vs. 100% by single nFe0). Theoretical calculations reveal the critical role of Pd in weakening the binding strengths of H* and N* on catalyst, which enables to reduce the H* adsorption and promote the migration of N* that increases the N*-N* encountering possibility for N2 formation. This correlation between surface chemistry and NO3– conversion may guide the design of improved Fe0-based materials for practical nitrate remediation.

Utilizing halogens as traceless directing goups represents an attractive strategy for C-H functionalization. A two C-H alkylation system, initiated by the oxidative addition of organohalides to Pd0 , has been developed. The first reaction involves an intermolecular alkylation of palladacycles to form C(sp3 )-C(sp2 ) bonds followed by C(sp2 )-H activation/cyclization to deliver alkylated benzocyclobutenes as the final products. In the second reaction, two C-C bonds are formed by the reaction of palladacycles with CH2 Br2 , and provides a facile and efficient method for the synthesis of indanes. The alkylated benzocyclobutene products can be transformed into tricyclic hyrocarbons, and the indane derivatives are essential structural motifs in bioactive and odorant molecules.

Electrocatalytic hydrodechlorination (EHDC) provides one promising solution to mitigate challenges from the water pollutions by persistent chlorinated organics. Palladium (Pd) has shown appealing properties as EHDC catalysts, while the low earth abundance has urged us to raise its activity and minimize usage. Herein, one novel semiconductor-metal Pd-TiO2 Schottky heterojunction catalyst was developed, which notably outperformed the conventional Pd-C catalyst in mass activity, dechlorination degree and energy selectivity towards EHDC of 2,4-dichlorophenol (2,4-DCP) in water. A combined experimental and DFT calculation study on mechanism revealed that the primary product phenol had a considerable negative effect on EHDC by competing the active sites with 2,4-DCP. The enhanced performance of Pd-TiO2 originated from the Schottky heterojunction-induced metal-support interactions, which optimized the Pd electronic structure and balanced the 2,4-DCP adsorption and phenol desorption on Pd. This study highlights one novel strategy to boost the metal performance in electrocatalytic hydrogenation reactions.