Albeladi Nawaf, Kur Anti, Mokaya Robert, Darkwa Jo, Roger-Lund Sarah, Worall Mark, Calautit John, Boukhanouf Rabah
School of Chemistry, University of Nottingham, Nottingham NG7 2RD, UK.
Department of Chemistry, Taibah University, Yanbu Al Bahr 46423, Saudi Arabia.
Materials (Basel). 2023 Sep 20;16(18):6296. doi: 10.3390/ma16186296.
The amount of waste heat generated annually in the UK exceeds the total annual electricity demand. Hence, it is crucial to effectively harness all available sources of waste heat based on their varying temperatures. Through suitable technologies, a substantial portion of this waste heat has the potential to be recovered for reutilization. Thermochemical energy storage (TCES) provides the best opportunities to recover waste heat at various temperatures for long-term storage and application. The potential of TCES with magnesium hydroxide, Mg(OH), has been established, but it has a relatively high dehydration temperature, thus limiting its potential for medium-temperature heat storage applications, which account for a vast proportion of industrial waste heat. To this end, samples of doped Mg(OH) with varying proportions (5, 10, 15, and 20 wt%) of potassium nitrate (KNO) have been developed and characterized for evaluation. The results showed that the Mg(OH) sample with 5 wt% KNO achieved the best outcome and was able to lower the dehydration temperature of the pure Mg(OH) from about 317 °C to 293 °C with an increase in the energy storage capacity from 1246 J/g to 1317 J/g. It also showed a monodisperse surface topology and thermal stability in the non-isothermal test conducted on the sample and therefore appears to have the potential for medium heat storage applications ranging from 293 °C to 400 °C.
英国每年产生的废热总量超过了年总电力需求。因此，根据不同温度有效利用所有可用的废热源至关重要。通过合适的技术，大部分废热有潜力被回收再利用。热化学储能（TCES）为在不同温度下回收废热进行长期存储和应用提供了最佳机会。氢氧化镁（Mg(OH)₂）热化学储能的潜力已得到证实，但其脱水温度相对较高，因此限制了其在占工业废热很大比例的中温蓄热应用中的潜力。为此，已制备了掺杂不同比例（5%、10%、15%和20%重量）硝酸钾（KNO₃）的Mg(OH)₂样品，并对其进行表征以进行评估。结果表明，含有5%重量KNO₃的Mg(OH)₂样品取得了最佳效果，能够将纯Mg(OH)₂的脱水温度从约317℃降至293℃，储能容量从1246 J/g增加到1317 J/g。在对该样品进行的非等温测试中，它还表现出单分散的表面拓扑结构和热稳定性，因此似乎有潜力用于293℃至400℃的中温蓄热应用。
