Study On Biomass-based Metal-loaded Desulfurization Adsorbent

With the increasing emphasis on ecological environment protection in today’s society,the task of producing ultra-low sulfur fuel oil is becoming more and more urgent.Therefore,the adsorption desulfurization method has broad application prospects.The desulfurization adsorbents loaded with metal activated carbons have been extensively studied because of their excellent adsorption and desulfurization performance.However,their further development is limited due to poor metal dispersion and complex preparation methods.Therefore,the purpose of this study is to prepare the metal-loaded adsorbent by biological method,which has high metal dispersion,stable performance and high adsorption desulfurization capacity.In this paper,we choose pistia stratiotes to adsorb heavy metals in water to make it into metal-rich plant body,and then prepare it into desulfurization adsorbent containing different metal species.The relationship between the concentration of heavy metals in water and the content and dispersion of metals in the corresponding adsorbents and their desulfurization performance was investigated;the types of heavy metals in the water and the desulfurization performance of desulfurization adsorbents prepared by the combination of different metals;and the different degrees of adsorbents changes in adsorption desulfurization performance after hydrophobic modification.This article also investigated the amount of adsorbent added and the regeneration situation,in order to discuss the optimal usage of adsorbent in the adsorption desulfurization process and its cycle times.In addition,by using kinetics,adsorption models and thermodynamics to fit the adsorbent adsorption desulfurization process in this study,it provides theoretical guidance for the corresponding actual production.Some of the adsorbents in this study were characterized by N₂adsorption desorption,scanning electron microscopy（SEM）,scanning electron microscope-mapping（SEM-mapping）,transmission electron microscopy（TEM）,fourier transform infrared spectroscopy（FTIR）,inductively coupled plasma atomic emission spectroscopy（ICP-AES）,water contact angle test,and steam adsorption test.The experimental results show that the adsorption desulfurization experiment showed that pistia stratiotes’plants were cultivated in Ni solution with different concentrations,and the total adsorption desulfurization ability of the adsorbent prepared by pistia stratiotes’leaves and roots showed no significant change,with the highest floating difference of only 2.3%.Therefore,the new adsorption desulfurization agent proposed in this study has wide applicability and practical significance.The increase of the metal content in the adsorbent and its adsorption desulfurization capacity are not always positively correlated,and this relationship only occurs in a certain range internal;comparison of PSAC@Ni with PSLAC-Ni（150）and PSRAC-Ni（10）shows that the preparation method of the metal-loaded adsorbent in this study is better than the conventional method such as impregnation method.Comparison of different metals,PSRAC-Ni,PSRAC-Co,PSRAC-Fe adsorption desulfurization capacity are 78 mg g^-1,72 mg g^-1,71 mg g^-1,respectively.PSRAC-Ni-Co adsorption desulfurization capacity in the bimetallic compound 87 mg g^-1,which has the highest adsorption desulfurization capacity.PDMS-PSAC-200 has the highest adsorption desulfurization capacity of 68 mg g^-1,which is higher than PDMS-PSAC-1 with the best hydrophobic properties.The hydrophobic modification of the adsorbent should not simply improve its hydrophobic performance.The kinetic model of the adsorbent’s adsorption and desulfurization process conforms to the quasi-first order,and the L_Fmodel can better fit the adsorption data.The q _LFvalue is closer to the experimental value.The adsorption process is spontaneous,exothermic,and the degree of freedom is reduced.In addition,the test results of the cyclic regeneration performance of the specific adsorbent show that the desulfurization performance after five thermal regeneration treatments can reach about 50%of the adsorption desulfurization performance of the fresh adsorbent.Therefore,the adsorbent prepared in this study The agent has wide applicability and relatively stable adsorption desulfurization ability.Moreover,the method used in this research not only solves the pollution problem of heavy metals in the water,but also uses pistia stratiotes to prepare a high-performance adsorption desulfurizer,which plays a dual role in the development of a green-friendly environment.…………………...