Thermodynamics, kinetics and reaction mechanism of hydrogen production from a novel Al alloy/NaCl/g-C3N4 composite by low temperature hydrolysis. (1st March 2021)

• Record Type: Journal Article
• Authors: Su, Ming; Hu, Haiping; Gan, Jianchang; Ye, Wenhua; Zhang, Wenhua; Wang, Huihu
• Is Part Of: Energy. Volume 218(2021)
• Publication Date: 2021-03-01
• Subjects: Al -- Hydrogen -- g-C3N4 -- Mechanical ball milling -- Mechanism; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2020.119489
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Real-time hydrogen production at low temperature can effectively solve the problem of hydrogen storage and transportation in cold area and plateau region. In this study, a novel Al alloy/NaCl/g-C3 N4 composite with enhanced low temperature reactivity for hydrogen production has been synthesized by mechanical ball milling method. The feasibility of Al-water reaction at the temperature of 253.15–373.15 K was firstly proved by thermodynamic calculation. The hydrogen generation performance was studied in tap water at 298.15 K and 23 wt% NaCl aqueous solution at low temperature of 253.15–273.15 K. The results indicated that the addition of g-C3 N4 can effectively promoted the hydrolysis of activated Al composites. Hydrogen yield of Al alloy/NaCl/g-C3 N4 composite with 1 g of g-C3 N4 addition reached 1006 mL·gAl −1 and the induction time of reaction was 90 s at 253.15 K, while that of Al alloy was only 230 mL·gAl −1 and 1120s respectively. It was supposed that the addition of g-C3 N4 effectively reduced the size of NaCl particles and promoted their uniform distribution in Al matrix and more cracks were generated. The kinetics and reaction mechanism using Al alloy/NaCl/g-C3 N4 composite were discussed. This study provides a new idea for the synthesis of Al composites with high reactivity at low temperature. Highlights: A novel Al alloy/NaCl/g-C3 N4 composite was prepared by ball milling. The feasibility of Al-water reaction was proved by thermodynamics analysis. Al alloy/NaCl/g-C3 N4 composite exhibited the enhanced reactivity at low temperature. The addition of g-C3 N4 can greatly reduce the activation energy of Al-water reaction. The hydrolysis mechanism of composites at low temperature were studied systematically.