Commercial Aluminum Hydroxides. Part 1: Phase Composition and Textural Characteristics of Commercial Aluminum Hydroxides/Oxides

Aluminum oxides are the most common component used in the design of heterogeneous catalysts of oil refining and petrochemistry. The optimum characteristics of aluminum oxide supports and catalysts (e.g., specific surface area, pore size, and phase and impurity compositions) correspond to the type of hydrocarbon feedstocks and technological process. In light of the trend toward import substitution, it is becoming ever more relevant to study the market for domestic producers of aluminum hydroxide feedstocks used in the synthesis of aluminum oxides. In this work, domestic commercial samples of aluminum hydroxides are investigated via X-ray diffraction, simultaneous thermogravimetry/differential scanning calorimetry, low-temperature nitrogen adsorption, and elemental analysis. It is established that the objects of study are most often inhomogeneous in phase and contain iron, silicon, and calcium impurities. The effect of degree of crystallinity and the sizes of coherent scattering regions in aluminum hydroxides with a predominantly boehmite structure (and in some cases, aluminum hydroxides containing bayerite) on the textural characteristics of synthesized aluminum oxides is demonstrated.