원자력 열을 이용한 요오드-황 열화학 수소 제조 사이클에서 분젠 공정 부분의 고효율 운전을 목적으로 2 액상(황산 상과 HIx 상)으로의 분리 및 H2O의 분배를 위한 H2SO4-HI-H2O-I2 혼합 계의 공정 특성을 연구하였다. 공정 변수 실험은 298~353 K의 온도 범위와 H2SO4/HI/H2O/I2 = 1/2/14~20/0.5~8.0의 몰 조성 범위에서 수행했다. 결과로서, SO2-I2-H2O 분젠 반응계를 위하여 계산에 의해 2 액상으로 분리되는 분리점 및 포화점의 사이의 범위를 결정하였다. 각 상내 불순물들(황산 상내 HI 및 I2 그리고 HIx 상내 H2SO4)이 최소화되는 최적의 결과는 가장 높은 온도인 353 K와 가장 높은 I2 몰 농도에서 얻을 수 있었다. 이 조건에서 황산 상을 위한 HI/H2SO4와 HIx 상을 위한 H2SO4/HIx 몰 비율은 각각 0.024와 0.028였다. 각 상으로 H2O의 분배를 위하여 HIx와 H2O 사이의 친화력이 H2SO4와 H2O 사이의 친화력보다 우세한 것으로 나타났으며, HIx와 H2O 사이의 친화력은 온도 증가에 따라 감소하고 I2 몰 농도에 따라 증가했다.

For highly efficient operation of a Bunsen process section in an iodine-sulfur thermochemical hydrogen production cycle using nuclear heat, the process characteristics of H2SO4-HI-H2O-I2 mixture system for separating into two liquid phases (H2SO4-rich phase and HIx-rich phase) and the distribution of H2O to each phase were investigated. The experiments for process variables were carried out in the temperature range, from 298 to 353 K, and in the H2SO4/HI/H2O/I2 molar ratio of 1/2/14~20/0.5~8.0. As the results, for the SO2-I2-H2O Bunsen reaction system, the ranges between the starting point and the saturation point for two liquid phases separation were determined by calculation. The best result for the minimization of impurities (HI and I2 in H2SO4 phase and H2SO4 in HIx phase) in each phase was obtained in an optimum condition with the highest temperature of 353 K and the highest I2 molar composition. In this condition, the HI/H2SO4 molar ratio in the H2SO4-rich phase and the H2SO4/HIx molar ratio in the HIx-rich phase were 0.024 and 0.028, respectively. For the distribution of H2O to each phase, it is appeared that the affinity between HIx and H2O was more superior to that between H2SO4 and H2O. The affinity between HIx and H2O was decreased with increasing temperature but increased with increasing I2 molar composition.

Iodine-Sulfur Cycle Hydrogen Production Bunsen Process Two Liquid Phases Separation H2O Distribution

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