In this paper, we present a new method for preparing γ-alumina nanoparticles with a bimodal pore size distribution by using an efficiently mixing membrane dispersion microreactor. NH₄HCO₃ and Al₂(SO₄)₃∙18H₂O were reacted under vigorous mixing to give an ammonium aluminum carbonate hydroxide (AACH) precursor. γ-Alumina was obtained by calcination of AACH at 550 °C for 6 h. The effects of NH₄HCO₃ concentration, pH during aging, and reaction temperature were investigated. The mechanism of bimodal pore formation was clarified. The results showed that large pores (10–100 nm) were mainly formed in the reactor and during aging, and small pores (0–10 nm) were mainly formed during calcination. When the concentration of NH₄HCO₃ was 1.5 mol/L, the aging pH was 9.2, and the reaction temperature was 80 °C, γ-alumina with a specific surface area of 504.7 m²/g and pore volume of 1.76 mL/g was obtained. The average size of the large pores was about 30 nm, and the average size of the small pores was about 4 nm.

在本文中，我们提出了一种通过使用有效混合的膜分散微反应器来制备具有双峰孔径分布的γ-氧化铝纳米粒子的新方法。在剧烈混合下使NH ₄ HCO ₃和Al ₂（SO ₄）₃ ∙18H ₂ O反应，得到氢氧化铝碳酸铵（AACH）的前体。通过在550°C下煅烧AACH 6小时获得γ-氧化铝。NH ₄ HCO _3的作用研究了浓度，老化过程中的pH值和反应温度。阐明了双峰孔形成的机理。结果表明，大孔（10–100 nm）主要在反应器中和老化过程中形成，而小孔（0–10 nm）主要在煅烧过程中形成。NH ₄ HCO ₃浓度为1.5 mol / L时，老化pH为9.2，反应温度为80℃，比表面积为504.7 m ² / g，孔容为1.76 mL / g的γ-氧化铝。得到g。大孔的平均尺寸为约30nm，而小孔的平均尺寸为约4nm。