Alumina Membranes for Desalination and Water Treatment

Abstract

In recent years, there has been a growing interest in utilizing inorganic membranes, particularly alumina (Al 2 O 3) ceramic membranes (CMs), and to address a variety of separation problems in miscellaneous industry. Al 2 O 3 membranes are commercially predominant in CMs market. Al 2 O 3 material is generally used either as membrane support and/or as membrane layer due to advantages provided by this material and its derivatives such as availability in tonnage quantities, chemical inertness, good hardness, and thermal stability of the porous texture during elaboration steps. In this chapter, we comprehensibly look at the recent studies related to desalination and water treatment by ultrafiltration (UF), nanofiltration (NF) Al 2 O 3 membrane, and highlight the separation properties of the membrane in specific environmental pollution. The influences of membrane operating conditions and water quality on the rejection of pollutant by Al 2 O 3 membrane are reported through a series of bench-level experiments.

Deposition of Thin Alumina Films Containing 3D Ordered Network of Nanopores on Porous Substrates

“…Alumina is a very good material for porous membranes because it is chemically stable, semitransparent, insoluble, inert, and biocompatible [ 17 , 18 , 19 ]. One of the very attractive applications of nanoporous alumina membranes is their incorporation into a wide variety of sensors [ 20 , 21 , 22 , 23 ], for filtration purposes [ 8 , 17 , 24 , 25 ] and water treatment [ 26 , 27 , 28 , 29 , 30 , 31 ].…”

New Generation of Mesoporous Silica Membranes Prepared by a Stöber-Solution Pore-Growth Approach

“…5 Although SiO 2 and γ-Al 2 O 3 membranes are less considered for water treatment and desalination applications, there is a growing interest in utilizing such membranes to address a variety of separation problems in miscellaneous industries. 6,7 Among these systems, silica membranes, consisting of ultrasmall and uniform nanometer-sized pores/channels, are promising systems for molecular filtration separation because of the possibility to combine high-flux and high-rejection properties. 8 The porosity, pore size, and tortuosity of acid-catalyzed sol− gel-derived silica layers can be tailored by incorporation of templating units during the synthesis.…”

“…On the other hand, ceramic NF and ultrafiltration (UF) membranes possess better properties such as high chemical, thermal, and mechanical stability, which makes them suitable for use in desalination and water treatment processes . Although SiO 2 and γ-Al 2 O 3 membranes are less considered for water treatment and desalination applications, there is a growing interest in utilizing such membranes to address a variety of separation problems in miscellaneous industries. , Among these systems, silica membranes, consisting of ultra-small and uniform nanometer-sized pores/channels, are promising systems for molecular filtration separation because of the possibility to combine high-flux and high-rejection properties…”

Development of porous membranes for water desalination

“…Among them, α-and γ-alumina have been frequently applied for membrane fabrication (55). α-Alumina can be obtained at a heat treatment temperature above 1000°C, it is the most stable form of alumina that can withstand extreme pH and thermal conditions (56). Nevertheless, the application range of the α-alumina is mostly MF, in reason of the large pores formed by the rapid crystal growth during the heat treatment (57).…”

“…Figure 2-8: (A) The forming of the crystal phases of Al2O3 based on the starting materials and heat treatment temperatures, and (B) the application range of α-alumina and γ-alumina for membrane synthesis(56,58) …”