Publications by authors named "Pengjia Dou"

Thin-film composite (TFC) membranes have gradually replaced some traditional technologies in the extraction, separation, and concentration of high value-added pharmaceutical ingredients due to their controllable microstructure. Nevertheless, devising solvent-stable, scalable TFC membranes with high permeance and efficient molecule selectivity is urgently needed to improve the separation efficiency in the separation process. Here, we propose phenolphthalein, a commercial acid-base indicator, as an economical monomer for optimizing the micropore structure of selective layers with thickness down to 30 nanometers formed by in situ interfacial reactions.

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Among the various types of materials with intrinsic porosity, porous organic cages (POCs) are distinctive as discrete molecules that possess intrinsic cavities and extrinsic channels capable of facilitating molecular sieving. However, the fabrication of POC membranes remains highly challenging due to the weak noncovalent intermolecular interactions and most reported POCs are powders. In this study, we constructed crystalline free-standing porous organic cage membranes by fortifying intermolecular interactions through the induction of intramolecular hydrogen bonds, which was confirmed by single-crystal X-ray analysis.

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The precise manipulation of the microstructure (pore size, free volume distribution, and connectivity of the free-volume elements), thickness, and mechanical characteristics of membranes holds paramount significance in facilitating the effective utilization of self-standing membranes. In this contribution, the synthesis of two innovative ester-linked covalent-organic framework (COF) membranes is first reported, which are generated through the selection of plant-derived ellagic acid and quercetin phenolic monomers in conjunction with terephthaloyl chloride as a building block. The optimization of the microstructure of these two COF membranes is systematically achieved through the application of three different interfacial electric field systems: electric neutrality, positive electricity, and negative electricity.

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To extract lithium from salt lake brine involves a process of separation and concentration. After separating lithium from brine, the lithium ion concentration is generally a few hundred mg/L which is far below the required 20-30 g/L (as Li) before precipitation as lithium carbonate. The concentration step of a lithium enriched brine is crucial but highly energy-intensive.

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Hemodialysis is one of the therapies for patients with kidney failure. Hemodialysis requires large amounts of pure water, and is one of the most water-hungry medical procedures, and thus represents a clear opportunity where improvements should be made concerning the consumption and wastage of water. In this paper, we explored the potential of forward osmosis (FO) membrane for recycling the spent dialysate using the dialysis concentrate as the draw solution.

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Forward osmosis has been widely used due to its advantages such as low energy consumption and low membrane fouling. Conventional treatment of vegetable industry wastes leaving the liquor an additional puzzle. The objective of this study is to evaluate the feasibility of reducing energy consumption by using forward osmotic membrane technology to concentrate vegetable liquor.

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