The work reports a novel strategy for combining polymers and metal–organic frameworks (MOFs) into composites for adsorption applications. Calcium silicate (CaSiO₃) was introduced into acrylonitrile butadiene styrene/thermoplastic polyurethane (ABS/TPU) alloy, and the CaSiO₃/ABS/TPU skeleton was fabricated by 3D printing technology. The Ca-MOF was directly loaded on the surface of acetone-etched 3D skeleton by in-situ growth method. The obtained 3D skeleton was characterized and the performance of methylene blue (MB) adsorption was determined. It is clear that Ca-MOF is successfully loaded on the surface of 3D skeleton due to the presence of CaSiO₃. The MB adsorption ratios of the solutions with initial concentrations of 50, 100 and 200 mg/L at the equilibrium time (5 h) are 88%, 88% and 80%, respectively, revealing good MB adsorption performance of the 3D skeleton. The MB adsorption ratio remains 70% at six runs of adsorption–desorption experiment, indicating the excellent recovering property of the skeleton. The results show that the prepared CaSiO₃/ABS/TPU 3D skeleton is a candidate adsorbent for printing and dyeing effluent treatment.

Both adsorption and photocatalysis are considered to be effective methods for removing organic contaminants from dye wastewater. In this study, the construction of 3D skeletons based on the nanoparticles ZnO and ABS/TPU/calcium silicate (CaSiO₃) (shortened as ATC) were fabricated via fused deposition molding (FDM) technology. Characterization by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) depicted that ZnO nanospheres had been successfully grown on the 3D skeleton surface with an enlarged specific surface area. As the results of the RhB adsorption and photocatalytic degradation experiments showed, the removal ratio of RhB onto the ZnO-ATC skeleton was as high as 97.94% and the synergistic effect of adsorption and photocatalysis greatly shortened the RhB degradation time under ultraviolet light irradiation. The nanocomposites synthesized in this study showed a significant removal ability for organic pollutants, and could effectively overcome the limitation of the secondary removal of photocatalysts.

Immobilization is considered as a promising strategy toward the practical applications of powdered adsorbent. Herein, three dimensional (3D) printing cylindrical capsules with cross-linked PVA hydrogels membrane in encapsulate Chlorella pyrenoidosa (Cp) were utilized for removal of lead ions. The chemical compositions, hydrogels performance and morphologies of the membranes were determined by Fourier transformed infrared spectroscopy (FTIR), cross-linking degree, swelling degree, membrane flux and scanning electron microscopy (SEM). It is found that PVA cross-linking structure is successfully synthesized on the surface of capsule body and cap due to the presence of PVA in the filament. The lead ions adsorption capacity related to initial concentration of 50 mg/L in 48 h is reached 75.61%, revealing a good removal ability. The self-floating 3D printed capsules device also shows an excellent recovering property. After 7 runs of adsorption experiment, the lead ions adsorption ratio remains 78.56%, which will bring a broad prospect in wastewater treatment, chemical slow release along with sample preparation and separation.

Adsorption is considered to be one of the most effective and economically viable technologies for removing contaminants from the environment. However, the disadvantages of its high-cost complicated process and difficulty in efficient recycling limit its practical application. Herein, a thermoplastic elastomer–polyvinyl alcohol composite (LAY-FOMM 60) sponge three-dimensional structure (3D printing sponge) was fabricated by the fused filament fabrication combined with water erosion technique. The size and shape of the resultant sponge were tailored, and the batch of adsorption/desorption experiments of Rhodamine B (RhB) onto the sponge was performed. The results show that the adsorption of RhB on the 3D printing sponge was mainly via physical adsorption, and pseudo-second-order and Langmuir models exhibited good correlation with the adsorption kinetic and isotherm data, respectively. Thermodynamic parameters suggest that the adsorption is an endothermic and spontaneous process. It is worth to note that the adsorption/desorption efficiency can be raised by compression. This results in high efficiency and low cost for adsorption/desorption process and benefit for regeneration of the adsorbent. The adsorption capacity was maintained over 85% of the initial capacity after being used for five cycles. The approach provides a simple strategy for manufacturing customizable porous adsorbent materials that meet various water treatment requirements.