Interaction between the water adsorption ability of aluminium-oxide-based sorbents and their chemical composition, acid-base properties of the surface, and textural characteristics has been analysed. Alumina desiccants were synthesized with the centrifugal–thermal activation of gibbsite followed by the hydration of the gibbsite under mild conditions. It was demonstrated that the multicyclic adsorption regeneration of samples under realistic conditions results in structural transformations and changes in the acidity of their surfaces and water adsorption ability. The modification of pseudoboehmite with alkali ions increases surface basicity and the dynamic capacity of adsorbents relating to water vapours. Equations have been presented that describe the adsorption and desorption processes taking place during water vapour adsorption with the materials studied.

The effect of alkali metal (Li, Na, K) incorporation on the morphology and water vapor uptake properties of mesoporous Al₂O₃ has been studied. The modification of the raw material, pseudoboehmite, represented a mixture of low-temperature phases (γ + η + χ)-Al₂O₃, and has been done at low-temperature that does not change the phase ratio. A decrease in specific surface values and an average pores size increase were observed as a result of the introduction of metal cations by impregnation and subsequent thermal treatment. The influence of the content of the modifying metal on the adsorption ability of the obtained samples in relation to water vapours has been studied. It has been established that alkaline modification Al₂O₃ with the lithium cations did not result in adsorption ability improvement, whereas samples that were modified with sodium or potassium in the amount of 1.2 weight % and 2.6 weight %, respectively, possess a higher equilibrium capacity (by ~40%), as compared to that of the initial sample (Al₂O₃), and a sufficiently high adsorption rate.

The review describes the main methods of obtaining hydroxides and aluminium oxides (AO) of various structures from gibbsite. The promising techniques of obtaining AO adsorbents are discussed, namely the technique of thermal activation in the mode of pneumatic transport with gibbsite by heated air (TCA Gb) and the technique of thermal activation of gibbsite in centrifugal flash reactors (CTA Gb). The main methods of improving the adsorbent properties of AO, such as the optimisation of texture characteristics and phase composition, as well as the influence of the modification of aluminium oxide adsorbents, obtained using CTA and TCA technologies with cations of alkaline metals, are considered. It is shown that the modification allows a controlled variation of the characteristics of donor and acceptor active sites on the surface of adsorbents and, thus, a substantial increase in their adsorption activity, in particular, with respect to water vapour.

The demand for biomass has been growing in recent years for several reasons, related to environmental, economic, and social trends. In the context of global climate changes and the depletion of natural resources, the recycling of plant biomass waste is a promising strategy for sustainable development that contributes to minimizing waste, improving resource efficiency, and achieving the goal of creating a circular economy. One of the highly demanded products of agricultural waste recycling is glucose. Glucose is an important organic substrate that allows a number of value-added products to be obtained. In this review, we focused on the commercially significant products of glucose oxidation: gluconic and glucaric acids. This review summarized the latest available data on the scope of the application of each product as well as the methods of their production. The capabilities and limitations of currently used methods of synthesis were highlighted.

The dynamic capacity of the commercial desiccant (NaX zeolite) and the adsorbent, synthesised based on low-temperature modifications of aluminium oxide, obtained from bayerite-containing hydroxide, was determined with respect to water vapour. Experimental studies were carried out using a pilot installation at the atmospheric pressure and increased pressure (up to 0.6 MPa) and high humidity. The increase in the height of the layer of the adsorbents leads to an increase of their dynamic capacity with respect to water vapour and the protective power (action) time of the layer. It was shown that at the atmospheric pressure and the pressure of up to 0.3 MPa, the dynamic capacity of NaX is greater; at a higher pressure, the adsorption capacity of the developed adsorbent Al₂O₃ becomes greater than the zeolite capacity, which allows recommending it as a desiccant at increased pressure.

A study is performed of the effect of the conditions of preparation (the nature and amount of alkali used to hydrate a gibbsite thermal activation product and the amount of nitric acid (acid modulus value) in preparing a moldable paste) on the properties of aluminum oxide desiccants. A desiccant is obtained that has higher dynamic capacity (more than 10.0 g/100 g) at close specific surface values of around 300 m²/g and higher static capacity (20–22 g/100 g) than foreign and Russian analogues. The desiccant has high strength of more than 8.0 MPa. Such a desiccant can improve the productivity of existing adsorbers and reduce the cost of sorbent regeneration, which is of undoubted practical interest.