Preparation of 2,5-Bis(Aminomethyl)Furan by Direct Reductive Amination of 2,5-Diformylfuran over Nickel-Raney Catalysts

The direct reductive amination of 2,5-diformylfuran (DFF) with ammonia to 2,5-bis(aminomethyl)furan (BAF) was demonstrated, for the first time, over the commercial type Nickel-Raney and acid treated Nickel-Raney catalysts. The effects of reaction parameters such as reaction medium, temperature and hydrogen pressure were described. The acid treated Nickel-Raney catalyst exhibited the highest BAF yield in the THF-water mixed reaction medium. The relatively higher Ni0 species composition and larger surface area of the acid treated Nickel-Raney catalyst with specific reaction conditions contributed greatly to the BAF formation. The oligomeric species, such as furanic imine trimers and tetramers confirmed by MALDI-MS analysis were presented as the intermediates of DFF reductive amination.

Silicate minerals control the potential uses of phosphorus-laden mineral-engineered biochar as phosphorus fertilizers

Silicate minerals constitute the main components in silicon(Si)-rich biomass,affecting the phosphorus(P)adsorption and release competencies of mineral-engineered biochar;however,the mechanisms underlying their differences remain largely unresolved.To examine these interactions,we investigated the mineralogical compositions and quantified the P-adsorption capacities of Al-,Fe-,Mn-,Zn-,and Mg-engineered biochars from Si-rich rice husk material.The potential uses of P-laden mineral-engineered biochar for P fertilizers were assessed using citric acid extraction.The results from X-ray diffraction,scanning electron microscopy,and Fourier transform infrared spectrometry revealed that mixed metal(oxyhydr)oxides and metal-silicate compounds precipitated in the biochar structure and acted as the main P adsorbents.Micro-crystalline silicates derived from the biomass-induced metal-silicate precipitates in all engineered biochars,which effectively retained the aqueous P with varying excellent capacities(25.6-46.5 mg/g)but relatively slow kinetics(48 h).The suitability of the Zn-,Mg-,Mn-,and Fe-biochars as P-recycled fertilizers was confirmed by the high amounts of citric acid extractable P(19-69%of the total P).Varying amounts of Zn,Mg,and Mn(34-47%of the total host metals)were also released from the engineered biochar through ligand-promoted dissolution.Our data shed light on the novel potential utilization of Mn-,Mg-and Zn-biochars from Si-rich biomass for P retrieval and their use for P,Mg,and micronutrient(Mn and Zn)fertilizers.Regarding the P removal capacity,the mineral-engineered biochar needed a longer adsorption period than conventional metal-engineered biochar.

Utilization of waste vanadium-bearing resources in the preparation of rare-earth vanadate catalysts for semi-hydrogenation of α,β-unsaturated aldehydes

Recycling industrial solid waste not only saves resources but also eliminates environmental concerns of toxic threats.Herein,we proposed a new strategy for the utilization of petrochemical-derived carbon black waste,a waste vanadium-bearing resource(V>30000 ppm(10−6)).Chemical leaching was employed to extract metallic vanadium from the waste and the leachate containing V was used as an alternative raw material for the fabrication of vanadate nanomaterials.Through the screening of various metal cations,it was found that the contaminated Na^(+)during the leaching process showed strong competitive coordination with the vanadium ions.However,by adding foreign Ce^(3+)and Y^(3+)cations,two rare-earth vanadates,viz.,flower-like CeVO_(4)and spherical YVO_(4)nanomaterials,were successfully synthesized.Characterization techniques such as scanning electron microscopy,transmission electron microscopy,X-ray diffraction,energy-dispersive X-ray spectroscopy,Fourier-transform infrared,and N2 physisorption were applied to analyze the physicochemical properties of the waste-derived nanomaterials.Importantly,we found that rare-earth vanadate catalysts exhibited good activities toward the semi-hydrogenation ofα,β-unsaturated aldehydes.The conversion of cinnamaldehyde and cinnamic alcohol selectivity were even higher than those of the common CeVO_(4)prepared using pure chemicals(67.2%vs.27.7%and 88.4%vs.53.5%).Our work provides a valuable new reference for preparing vanadate catalysts by the use of abundant vanadium-bearing waste resources.