Immobilized inorganic diffusion barriers and the use thereof in the separation of small molecular species from a solution

TLDR: In this article, the modification of a diffusion barrier by the deposition of one or more inorganic species within the pores and on the surfaces of said diffusion barrier to form an immobilized crystalline lattice barrier or molecular grid having substantially uniform permeability and to select and separate different ionic species, giving a high efficiency of separation with a low energy input.

Abstract: The modification of a diffusion barrier by the deposition of one or more inorganic species within the pores and on to the surfaces of said diffusion barrier to form an immobilized crystalline lattice barrier or molecular grid having substantially uniform permeability and to select and separate different ionic species, giving a high efficiency of separation with a low energy input. The diffusion barrier is characterized by one or more units, each incorporating a tubular housing with a bundle of porous hollow fibres therein, arranged in the axial direction of the housing. The inorganic crystalline lattice is exemplified by barium sulphate (BaSO 4 ) formed by the interdiffusion of barium hydroxide (Ba(OH) 2 ) and sulphuric acid (H 2 SO 4 ) solutions, or, alternatively, co-precipitated aluminium hydroxide (Al(OH) 2 ) and barium sulphate (BaSO 4 ) formed by the interdiffusion of barium hydroxide (Ba(OH) 2 ) and aluminium sulphate (Al 2 (SO 4 ) 3 ) solutions. These immobilized inorganic diffusion barriers are used for selective separation of small molecules (e.g. with a molecular weight of less than 1000 daltons) and provide means for the more effective separation of ionic species. A method is also provided for the low cost removal of ions from molasses, to enhance fermentation efficiency and to improve its usefulness as a stock feed supplement, or it may be followed by other treatments to reduce and/or remove higher molecular weight substances, such as proteins and waxes, to produce sugar syrups and caramel substitutes.