Cu/ZSM5-Geopolymer 3D-Printed Monoliths for the NH3-SCR of NOx

Geopolymer-based monoliths manufactured by direct ink writing, containing up to 60% by weight of presynthesized ZSM5 with low Si/Al ratio, were investigated as structured catalysts for the NH3-SCR of NOx. Copper was introduced as the active metal by ion exchange after a preliminary acid treatment of the monoliths. Monolithic catalysts were characterized by morphological (XRD and SEM), textural (BET and pore size distribution), mechanical (compressive strength), chemical (ICP–MS), redox (H2-TPR) and surface (NH3-TPD) analyses, showing the preservation of Cu-exchanged zeolite features in the composite monoliths. NH3-SCR tests, carried out on both monolithic and powdered samples in the temperature range 70–550 °C, confirmed that composite monoliths provide a very good activity and a high selectivity to N2 over the whole range of temperatures explored due to the hierarchical structure of the materials, in addition to a good mechanical resistance—mostly related to the geopolymer matrix.

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The synergistic effects between Ce and Cu in CuyCe1−yW5Ox catalysts for enhanced NH3-SCR of NOx and SO2 tolerance

Catalysis Science & Technology ◽

10.1039/c8cy01949e ◽

2019 ◽

Vol 9 (3) ◽

pp. 718-730 ◽

Cited By ~ 17

Author(s):

Jian-Wen Shi ◽

Yao Wang ◽

Ruibin Duan ◽

Chen Gao ◽

Baorui Wang ◽

...

Keyword(s):

Metal Oxides ◽

Selective Catalytic Reduction ◽

Low Temperatures ◽

Catalytic Reduction ◽

Synergistic Effects ◽

Reduction Of No ◽

Nh3 Scr ◽

So2 Tolerance ◽

Scr Of Nox

Non-manganese-based metal oxides are promising catalysts for the NH3-SCR (selective catalytic reduction) of NOx at low temperatures.

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Continuous Based Direct Ink Write for Tubular Cardiovascular Medical Devices

Polymers ◽

10.3390/polym13010077 ◽

2020 ◽

Vol 13 (1) ◽

pp. 77

Author(s):

Enric Casanova-Batlle ◽

Antonio J. Guerra ◽

Joaquim Ciurana

Keyword(s):

Medical Devices ◽

New Technology ◽

Vascular Grafts ◽

Mechanical Resistance ◽

Medical Applications ◽

End User ◽

Cardiovascular Stents ◽

Direct Ink Writing ◽

Late Restenosis ◽

Printing Parameters

Bioresorbable cardiovascular applications are increasing in demand as fixed medical devices cause episodes of late restenosis. The autologous treatment is, so far, the gold standard for vascular grafts due to the similarities to the replaced tissue. Thus, the possibility of customizing each application to its end user is ideal for treating pathologies within a dynamic system that receives constant stimuli, such as the cardiovascular system. Direct Ink Writing (DIW) is increasingly utilized for biomedical purposes because it can create composite bioinks by combining polymers and materials from other domains to create DIW-printable materials that provide characteristics of interest, such as anticoagulation, mechanical resistance, or radiopacity. In addition, bioinks can be tailored to encounter the optimal rheological properties for the DIW purpose. This review delves into a novel emerging field of cardiovascular medical applications, where this technology is applied in the tubular 3D printing approach. Cardiovascular stents and vascular grafts manufactured with this new technology are reviewed. The advantages and limitations of blending inks with cells, composite materials, or drugs are highlighted. Furthermore, the printing parameters and the different possibilities of designing these medical applications have been explored.

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3D Printed Masks for Powders and Viruses Safety Protection Using Food Grade Polymers: Empirical Tests

Polymers ◽

10.3390/polym13040617 ◽

2021 ◽

Vol 13 (4) ◽

pp. 617

Author(s):

Ruben Foresti ◽

Benedetta Ghezzi ◽

Matteo Vettori ◽

Lorenzo Bergonzi ◽

Silvia Attolino ◽

...

Keyword(s):

Surface Roughness ◽

Additive Manufacturing ◽

Material Selection ◽

Mechanical Resistance ◽

Biological Safety ◽

Fused Deposition ◽

Industrial Grade ◽

Safety Protection ◽

3D Printed ◽

Manufacturing Technologies

The production of 3D printed safety protection devices (SPD) requires particular attention to the material selection and to the evaluation of mechanical resistance, biological safety and surface roughness related to the accumulation of bacteria and viruses. We explored the possibility to adopt additive manufacturing technologies for the production of respirator masks, responding to the sudden demand of SPDs caused by the emergency scenario of the pandemic spread of SARS-COV-2. In this study, we developed different prototypes of masks, exclusively applying basic additive manufacturing technologies like fused deposition modeling (FDM) and droplet-based precision extrusion deposition (db-PED) to common food packaging materials. We analyzed the resulting mechanical characteristics, biological safety (cell adhesion and viability), surface roughness and resistance to dissolution, before and after the cleaning and disinfection phases. We showed that masks 3D printed with home-grade printing equipment have similar performances compared to the industrial-grade ones, and furthermore we obtained a perfect face fit by customizing their shape. Finally, we developed novel approaches to the additive manufacturing post-processing phases essential to assure human safety in the production of 3D printed custom medical devices.

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Direct ink writing of organic and carbon aerogels

Materials Horizons ◽

10.1039/c8mh00603b ◽

2018 ◽

Vol 5 (6) ◽

pp. 1166-1175 ◽

Cited By ~ 22

Author(s):

Swetha Chandrasekaran ◽

Bin Yao ◽

Tianyu Liu ◽

Wang Xiao ◽

Yu Song ◽

...

Keyword(s):

Additive Manufacturing ◽

Ion Transport ◽

Carbon Aerogels ◽

Direct Ink Writing ◽

3D Printed ◽

Fast Ion ◽

Large Capacitance

Additive manufacturing is used to overcome inherent aerogel limitations. 3D printed aerogels simultaneously exhibit large capacitance and fast ion transport in millimeter-thick electrodes.

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