This paper investigates the application of K₂CO₃ supported onto porous alumina, as sorbent for selective CO₂ capture in marine applications. Alumina-functionalized sorbents were prepared by incipient wetness impregnation achieving K₂CO₃ loadings from 3.6 to 14.1% wt. Carbonation tests were performed in a fixed-bed column at temperatures between 60 and 105 °C, as those typically occurring at the outlet of a scrubber and/or a waste heat recovery unit, with a model diesel engine exhaust (5% vol. CO₂, 5% vol. H₂O, balance N₂). According to the carbonate loading, the sorbents may reach conversion degrees of carbonate up to 90% and overall capture capacity up to 0.66 mol kg⁻¹ sorbent. Experimental data showed higher conversion degree and capture capacity compared with unsupported K₂CO₃, which is affected by significant intraparticle diffusion limitations. Steam regeneration tests performed in a fixed-bed column on the sorbent with 3.6% wt K₂CO₃ loading revealed that a temperature of 120 °C assures almost complete recovery of captured CO₂ while preserving the sorbent carbonation degree for 10 consecutive carbonation/regeneration cycles. The preliminary design of a temperature swing carbonation/regeneration unit for on-board ship installation was performed for the reference case study of a passenger ship equipped with a 4.35 MW marine engine fueled with marine gas oil and with a commercial seawater scrubber for SO₂ removal. The proposed unit appeared able to cut up to 30% carbon dioxide emission by using the sorbent containing 3.6% wt K₂CO₃ and operating the carbonation and regeneration stage at 60 and 120 °C, respectively.

本文研究了负载在多孔氧化铝上的K ₂ CO ₃作为吸附剂在海洋应用中选择性捕获CO _2的应用。通过初期湿润浸渍来制备氧化铝官能化的吸附剂，以使K ₂ CO _3的负载量为3.6至14.1 wt％。碳化试验是在固定床塔中于60至105°C之间的温度下进行的，通常在洗涤器和/或废热回收装置的出口进行，并使用柴油机排气模型（5％体积的CO）。₂，体积H ₂ O的5％，平衡N ₂）。根据碳酸盐的负载量，吸附剂可以达到高达90％的碳酸盐转化率和高达0.66 mol kg ^-1吸附剂的总捕获能力。实验数据显示，与不受支持的K ₂ CO ₃相比，其转化度和捕获能力更高，而K ₂ CO ₃受到明显的颗粒内扩散限制。在固定床色谱柱上吸附量为3.6％wt K ₂ CO ₃的吸附剂上进行的蒸汽再生测试表明，120°C的温度可确保几乎完全回收捕获的CO ₂同时保持吸附剂碳酸化度连续10次碳酸/再生循环。进行了船上安装的变温碳酸化/再生装置的初步设计，以对某客船进行参考案例研究，该客船配备了4.35 MW船用柴油机，该船用柴油供船用瓦斯油，并配有商用海水洗涤塔，用于去除SO _2。。通过使用包含3.6％wt K ₂ CO ₃的吸附剂并分别在60和120°C下运行碳酸化和再生阶段，拟议的装置似乎能够减少多达30％的二氧化碳排放。