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Evaluation of a Ti-Base Alloy as Steam Cracking Reactor Material.

ABSTRACT: Low-coking reactor material technologies are key for improving the performance and sustainability of steam crackers. In an attempt to appraise the coking performance of an alternative Ti-base alloy during ethane steam cracking, an experimental study was performed in a jet stirred reactor under industrially relevant conditions using thermogravimetry (T_gasphase = 1173 K, P_tot = 0.1 MPa, X_C2H6 = 70%, and dilution δ = 0.33 kg_H2O/kg_HC). Initially, a typical pretreatment used for Fe-Ni-Cr alloys was utilized and compared with a pretreatment at increased temperature, aiming at better surface oxidation and thus suppressing coke formation. The results revealed a decrease in coking rates upon high temperature pretreatment of the Ti-base alloy, however, its coking performance was significantly worse compared to the typically used Fe-Ni-Cr alloys, and carbon oxides formation increased by a factor of 30 or more. Moreover, the analyzed coupons showed crack propagation after coking/decoking and cooling down to ambient temperature. Scanning electron microscopy combined with energy-dispersive X-ray spectroscopy indicated that the prompt and unsystematic oxidation of the surface and bulk caused observable crack initiation and propagation due to alloy brittleness. Hence, the tested Ti-base alloy cannot be considered an industrially noteworthy steam cracking reactor alloy.

SUBMITTER: Sarris SA

PROVIDER: S-EPMC6719091 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Biomechanical evaluation of Ti-Nb-Sn alloy implants with a low Young's modulus.

Project description:Dental implants are widely used and are a predictable treatment in various edentulous cases. Occlusal overload may be causally related to implant bone loss and a loss of integration. Stress concentrations may be diminished using a mechanobiologically integrated implant with bone tissue. The purpose of this study was to investigate the biomechanical behavior, biocompatibility and bioactivity of a Ti-Nb-Sn alloy as a dental implant material. It was compared with cpTi. Cell proliferation and alkaline phosphatase (ALP) activity were quantified. To assess the degree of osseointegration, a push-in test was carried out. Cell proliferation and ALP activity in the cells grown on prepared surfaces were similar for the Ti-Nb-Sn alloy and for cpTi in all the experiments. A comparison between the Ti-Nb-Sn alloy implant and the cpTi implant revealed that no significant difference was apparent for the push-in test values. These results suggest that implants fabricated using Ti-Nb-Sn have a similar biological potential as cpTi and are capable of excellent osseointegration.

| S-EPMC4394505 | biostudies-literature

Long-term survivorship of an exchangeable-neck hip prosthesis with a Ti-alloy/Ti-alloy neck-stem junction.

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| S-EPMC10192172 | biostudies-literature

Optimal Synthesis and Application of a Si-Ti-Al Ternary Alloy as an Anode Material for Lithium-Ion Batteries.

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Project description:With energy savings

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| S-EPMC5457277 | biostudies-other

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| S-EPMC7191259 | biostudies-literature

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| S-EPMC8748655 | biostudies-literature

The Influence of Cryogenic Conditions on the Process of AA2519 Aluminum Alloy Cracking.

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| S-EPMC7178225 | biostudies-literature

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| S-EPMC7193587 | biostudies-literature

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