Preparation Of Molasses-based Porous Carbon Materials And Its Adsorption Toward Anisole And CO₂/CH₄

In this paper,the potential application background is the aroma release in the daily chemical field and CO₂ capture in the environmental protection field.The molasses is used as carbon source to develop a novel porous carbon material with excellent properties.This paper mainly involves the preparation of molasses-based porous carbon materials,the research on the slow-release properties and diffusion mechanism of sample materials towards aroma,and the study on CO₂ capture and adsorptive separation of CO₂/CH₄.Those all have theoretical research and practical application value.In this paper,a series of molasses-based porous carbon materials were prepared from cane molasses.The anisole adsorption capacity of sample MACs-800-5 was up to 1823 mg/g,and the anisole desorption rate was 86.8%.Those data all met the needs of practical application.The analysis results of the diffusion coefficient De estimation model revealed that the desorption process of anisole molecules on adsorbent material first undergoes general diffusion and then Knudsen diffusion,finally,surface diffusion.Knudsen diffusion and surface diffusion play a leading role in the slow-release process.The pore structure of material plays a key role in the diffusion mechanism.The larger the proportion of material micropores,the larger the proportion of surface diffusion.In this paper,the performance for CO₂ capture and adsorptive separation of CO₂/CH₄ on the molasses-based porous carbon materials were systematically studied.The ultra-micropores volume of sample MACs-800-2 reached 0.273 cm³/g.And its CO₂ adsorption capacity was 3.69mmol/g at 298K and 1 bar.CO₂/CH₄ selectivity was in the range of 3.45-4.01.In this paper,the dicyandiamide was used as a modifier to synthesize a series of molasses-based porous carbon materials with high ultra-micropore volume by one-step method.And their performance for CO₂ capture and adsorptive separation of CO₂/CH₄ were systematically studied.Among them,the ultra-micropores volume of the sample 0.3D-MACs reached 0.373 cm³/g,and its CO₂ adsorption capacity reached as high as 4.66 mmol/g at 298K and 1 bar,which is 23%higher than the original carbon material.This was mainly due to the introduction of dicyandiamide,which increased the N-containing functional groups on the surface of the materials and produced more ultra-micropores void structure.0.3D-MACs for CO₂/CH₄selectivity was in the range of 5-6,which is significantly higher than the original carbon material.The breakthrough curves in fixed-bed proved that 0.3D-MACs had excellent CO₂/CH₄ separation performance.