19052-59-6Relevant articles and documents
Highly efficient reduction of 4-nitrophenolate to 4-aminophenolate by Au/γ-Fe2O3@HAP magnetic composites
Xia, Yide,Liu, Ying,Shi, Nannan,Zhang, Xungao
, p. 10272 - 10281 (2019)
In this article, the catalyst Au/γ-Fe2O3@hydroxyapatite (Au/γ-Fe2O3@HAP) consisting of Au nanoparticles supported on the core-shell structure γ-Fe2O3@HAP was prepared through a deposition-precipitation method. The catalyst was characterized by transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, N2 adsorption-desorption and atomic absorption spectrometry. The as-prepared Au/γ-Fe2O3@HAP exhibited excellent performance for the reduction of 4-nitrophenolate (4-NP) to 4-aminophenolate (4-AP) in the presence of NaBH4 at room temperature. Thermodynamic and kinetic data on the reduction of 4-NP to 4-AP catalyzed by the as-prepared catalyst were studied. The as-prepared catalyst could be easily separated by a magnet and recycled 6 times with over 92% conversion of 4-NP to 4-AP. In addition, the as-prepared catalyst showed excellent catalytic performance on other nitrophenolates. The TOF value of this work on the reduction of 4-NP to 4-AP was 241.3 h-1. Au/γ-Fe2O3@HAP might have a promising potential application on the production of 4-AP and its derivatives.
Ag-Fe3O4 nanocomposites@chitin microspheres constructed by in situ one-pot synthesis for rapid hydrogenation catalysis
Duan, Bo,Liu, Feng,He, Meng,Zhang, Lina
, p. 2835 - 2845 (2014)
The fabrication of reusable and biodegradable materials from renewable resources such as chitin is essential for a sustainable world. In the present work, chitin was dissolved in 11 wt% NaOH-4 wt% urea aqueous solution via freezing-thawing, and then chitin microspheres (RChS) were prepared by a sol-gel transition method. Subsequently, novel magnetic Ag-Fe3O 4@chitin microspheres (MRChS) were constructed successfully by an in situ one-pot synthesis of Ag-Fe3O4 nanoparticles onto the RChS surface. The magnetic chitin microspheres displayed a spherical shape with a 3D-mesh structure, and had a narrow size distribution (150-400 μm). There were many micro- and nano-pores existing in MRChS, and the Ag-Fe 3O4 nanoparticles were immobilized through anchoring with the acetyl amine groups of chitin in these pores. The MRChS microspheres were used as a chromatography column packing material for a catalytic reaction column , and exhibited highly effective catalytic activity in the rapid transformation from 4-nitrophenol to 4-aminophenol. Moreover, the microspheres displayed a small hysteresis loop and low coercivity, as well as high turnover frequency (at least 10 times) without any loss of catalytic activity. Thus, MRChS could be quickly removed from the water under a magnetic field, leading to easy recycling and reuse. Therefore, this is an environmentally friendly process, and would be highly beneficial to address industrial requirements. the Partner Organisations 2014.
A Broader-scope Analysis of the Catalytic Reduction of Nitrophenols and Azo Dyes with Noble Metal Nanoparticles
Shultz, Lorianne R.,Hu, Lin,Preradovic, Konstantin,Beazley, Melanie J.,Feng, Xiaofeng,Jurca, Titel
, p. 2590 - 2595 (2019/05/15)
In addition to the broad environmental implications associated with the removal of nitroaromatics from industrial effluent, the catalytic reduction of 4-nitrophenol (4NP) has emerged as a benchmark model for quantifying catalytic activity of metal nanoparticles. Here we present a series of noble metal nanoparticles immobilized on amorphous carbon (Au@C, Ag@C, Pt@C and Pd@C). All materials show competitive catalytic activity over 4NP, amino-substituted nitrophenols (ANPs) and azo dyes. Overall, Pd@C exhibits superior activity that increases further when exposed to recycling protocol. Moreover, testing all materials synthesized over a broader substrate scope with added functionalities reveals inconsistencies in the prognosticating ability of the ubiquitous 4NP model reaction. By incorporating variably substituted ANPs into the substrate scope and averaging performance, the resulting rank of catalyst activity more accurately reflects activity trends when applied to other reducible functionalities, such as -N=N- groups in azo dyes.
