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Tubular porous silicate cement compacts with hierarchical porosity were successfully fabricated via a tert-butyl alcohol (TBA)-based freeze-casting technique in one single step. These samples were characterized by unidirectional aligned pore channels and completely open porosity. Various experimental parameters affecting the macropore size, mesopore size, porosity, and compression strength were investigated, including the initial solids loading, freezing temperature and curing period. Both the research findings of microstructure observations and property tests show that the pore size decreased significantly with decreasing freezing temperature and increasing solids loading. The porosity increased significantly with decreasing solids loading, while the compressive strength decreased remarkably. In addition to their tunable physical characteristics, these brand-new inorganic porous materials with oriented aligned pore channels and dense layer surface showed high permeation performance and desirable separation ability. These results endow the silicate cement, a kind of low-cost and high-performance architecture material, with great potential as a novel ordered porous inorganic material for numerous applications, especially in separation process. [ABSTRACT FROM AUTHOR]

[Display omitted] • NF-like iTFC FO membrane was paired with a high-valence food additive. • C 6 H 5 K 3 O 7 was identified as the optimal draw solute for pre-concentrating fruit juice. • MgSO 4 was found to be suitable for further concentration of fruit juice. • One dual-stage and dual-cycle FO was proposed without the need of DS recovery. • A hybrid system can establish a relationship between fruit and juice production. The technology of forward osmosis (FO) has garnered increasing research interest for its excellent advantages in producing high-quality concentrated juice. However, the practical application of FO to concentrate juice is hindered by the lack of an appropriate FO membrane and matched draw solution. To address this challenge, several additives containing high-valence ions were investigated to improve the feasibility of the FO process for juice concentration, using a nanofiltration(NF)-like FO membrane with an interlayer constructed by MOFs-based nanoparticles. The prepared NF-like FO membranes exhibited negative potential, superior hydrophilicity, and uneven crosslinking, which matched well with five selected additives (C 6 H 8 O 7 , K 2 SO 4 , C 6 H 5 K 3 O 7 , MgSO 4 , and KH 2 PO 4), potentially preventing bacterial growth on the membrane surface during the concentration process and contributing to the growth of plants. A comprehensive comparison of selected five additives indicated that, with the exception of MgSO 4 , these additives at their saturated concentration exhibited marginally higher osmotic pressure than that of the fresh juice, indicating their limited suitability for further concentration of the fresh juice. However, during the pre-concentration phase of the fresh juice, the juice concentration is lower than that of the fresh juice due to the additional water incorporated during the juice production process. C 6 H 5 K 3 O 7 was the optimal draw solution for pre-concentrating apple juice, while MgSO 4 was better suited for further concentrating fresh juice. The concentrations of C 6 H 5 K 3 O 7 and MgSO 4 in the final juice were well below their limit value. Based on these results, a proposal for a dual-stage and dual-cycle FO process has demonstrated to achieve highly efficient concentration of fruit juice and seamless integration of juice production and fertigation of fruit trees, without the need to consider draw solution recovery. [ABSTRACT FROM AUTHOR]

• Smooth (R a less than 2 nm) surface of the GQDs-interlayered membrane was achieved. • The 25 nm-thick skin layers of the GQDs-interlayered membranes. • The GQDs-PEI interlayer covalent bonded between substrate and skin layer. • The prepared membrane maintained stable performance in DMF for 45 days at 80 °C. Novel thin film nanocomposite (TFN) organic solvent nanofiltration (OSN) membranes with sandwich-like structure were developed via interfacial polymerization (IP) using both low concentration m-phenylenediamine (MPD) and trimesoyl chloride (TMC), on graphene quantum dots (GQDs)-polyethyleneimine (PEI) modified polyimide substrate surface, and followed by post-IP crosslinking and solvent activation. Such GQDs-interlayered OSN membranes have exhibited a remarkable reduced thickness (about 25 nm) and an ultra-low average surface roughness (less than 2 nm) of their IP skin layers, respectively. Both material features are rarely reported in literature. Meanwhile, our GQDs-interlayered OSN membranes have shown an increased Rhodamine B (479 Da) rejection (from 87.4% to 98.7%) and an increased ethanol permeance (from 33.5 to 40.3 L m−2 h−1 MPa−1) compared with the pristine OSN membrane. Superior solvent resistance was demonstrated after long immersion in pure N , N -dimethylformamide (DMF) at room temperature for 81 days, and at 80 °C for 45 days, and after a long-term consecutively filtration with Rose Bengal (1017 Da) DMF solution at 25 °C for 5 days, without scarifying solute rejection. Antifouling properties during the long-term filtration were also indicated. This paper presents a novel GQDs-interlayered strategy in developing high-performance TFN membranes for OSN application. [ABSTRACT FROM AUTHOR]