| H2S is a toxic and harmful gas, it can bring not only serious threat to human health, cause catalyst poisoning, but also corrode equipment in hot and humid conditions, make cost increased, contribute to a series of problems. In addition, H2S burns into SO2, forming acid rain, resulting in environmental pollution. Removal of H2S produced in industrial production is an urgent issue to solve.In this paper, raw carbon frow ChangGe were as precursors of the desulphurizer. A series of H2S removal agents of modified samples were prepared from raw carbon by means of HNO3 oxidation, heat treatment at high temperature and impregnated with metal nitrate solution as well as their combined modifications.Adopt non-aqueous titration to determine the content of acid and basic groups of raw carbon and a series of samples. Titration results showed that the surface acidity group content more on raw material, presented acidic entirety. Nitric acid modification made a sharp decrease of basic groups and it had a strong acid surface. After firing under nitrogen atmosphere at 400℃the basic groups increased, but the surface still presented acidic. Samples impregnated with metal nitric acid had their basic groups increased in different degree, sample impregnated with nitric acid iron increased most almost 43.73%.Industrial analysis results showed that the carbon had higher ash and volatile, lower fixed carbon content. The nitric had obvious effect of ash removal, the ash content of sample oxidatd by HNO3 which concentration was 45% fell from 12.06% to 8.53%, but there were notable increases of volatile specifics. High temperature firing made volatile dropped by nearly 35%, fixed carbon content were increased by 33% yet. Surface area and pore volume of raw carbon were low, 349.94m2/g and 0.2150cm3/g respectively. After modified by many steps, the surface area sharply increased to 835.67 m2/g, at the same time pore volume of the modified sample more than doubled.The capacity of H2S and effect of process operation on H2S removal activities for various samples were investigated in fixed bed reactor in simulated syngas at low temperature. Results showed that raw material presented poor activity and soon to penetrate. With the same concentration of HNO3 at the same temperature the activation time increased. Impregnated with Fe (NO3)3, Cu (NO3)2 and Mn (NO3)2 all can improve desulfurization effect, among which impregnated with Fe (NO3)3 presented the best effect. The best operating conditions were as follows the best temperature was 30℃, the suitable H2O steam content was 3%, and O2 content about 1.5%.It has been done the dynamics research according to the relationship between temperature and the reaction rate. The results showed that the influence of reaction temperature was complicated. With the basic functional groups contents of surface amplified, the sulfur let increased, and they had an obvious linear relationship. SEM images showed that the pore structure was not obvious at preparation process. EDS displayed sample impregnented with nitric acid iron the content of S had a great increase after desulfurization, about 12.65 times of the fresh sample, but sulfur-containing were not found in XRD spectras.Water washing regeneration, H2O2 regeneration, hot regeneration and their combination were used in regeneration experiment. Experimental results showed that the effect of washing-hot regeneration was the best, maximum sulfur volume regeneration rate reached to 82.91%, after three times regeneration the sulfur volume regeneration rate was 57.32%. Neither single regeneration method by water washing nor H2O2 was ideal, the sulfur volume regeneration rate was less than 15%. |
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