Ba-modified Ni-P amorphous alloy/acidified bentonite catalyst: preparation and the catalytic hydrogenation of nitrobenze

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Ba-modified Ni-P amorphous alloy/acidified bentonite catalyst: preparation and the catalytic hydrogenation of nitrobenzene to aniline Tongming Su1 · Yuexiu Jiang1 · Yun Xu1 · Xuan Luo1 · Xinling Xie1 · Zuzeng Qin1   · Hongbing Ji1,2 Received: 14 August 2020 / Accepted: 18 October 2020 © Akadémiai Kiadó, Budapest, Hungary 2020

Abstract In the present work, a Ba-modified Ni-P amorphous alloy/acid bentonite catalyst (Ni-P A/B) was prepared, and used for nitrobenzene hydrogenation to aniline in the liquid phase. The results showed that Ba addition could increase the dispersion of the active component Ni on the support and further form more Ni active centers. The addition of Ba could provide electrons for Ni, increasing the electron cloud density around Ni and improving the hydrogenation activity of the catalyst. At the condition of a Ba addition amount of 3.0%, a hydrogen pressure of 1.4  MPa, and a reaction temperature of 105 °C, the optimal nitrobenzene conversion and aniline selectivity was 99.0% and 98.9%, respectively. The catalyst maintained excellent stability when it was reused 10 times, which was 4 times greater than that of Ni-P A/B. Keywords  Barium · Amorphous alloy · Bentonite · Nitrobenzene · Hydrogenation · Aniline · Stability

Introduction Aniline (AN) is an important organic compound and reaction intermediate, which was used in many industrial fields, such as rubber chemicals, dyes, organic pigments, amino resins, polyurethanes, cyclohexylamine, pharmaceuticals, and pesticides [1, 2]. In the fields of polyurethane and rubber, AN was raw material and additive, and the demand for aniline was the largest and obtained the most rapid growth in recent years.

* Zuzeng Qin [email protected]; [email protected] 1

School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China

2

School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China



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Reaction Kinetics, Mechanisms and Catalysis

In general, AN is manufactured by the nitrobenzene hydrogenation [3, 4], including catalytic hydrogenation of nitrobenzene in the gas-solid and liquid-phase. Because the aromatic nitro compounds exhibited high boiling points and thermal instability, the liquid-phase process would be much better for industrial production. Moreover, liquid-phase catalytic hydrogenation has the following advantages: a higher heat transfer coefficient, which causes a higher and more stable yield of hydrogenation, greater utilization of the reaction heat, environmental friendliness, mild reaction conditions (temperature and pressure are relatively low), and a more straightforward reaction process. Therefore, the liquid-phase method received more attention in recent years [5–7]. The commonly used catalysts for nitrobenzene hydrogenation in the liquid phase are precious metal catalysts [8–10], and Ni-based catalysts [4, 11–14], and amorphous alloy catalysts [15, 16]. Because of the high catalytic activity, mild reaction conditions, and long catalyst life, precious metal catalysts occupy