沥青基多孔碳材料的制备及应用性能研究

发布时间：2018-10-09 07:39

【摘要】：新型的多孔碳材料如高比表面积的活性炭和高疏水高吸油性能的大孔炭等由于其独特的孔径结构而具有优异的气体吸附、油品吸收等性能,从而广泛应用于气体存储/分离、油水分离/溢油处理等方面。目前,如何高效、环保、经济的制备这些碳材料是当今科学界面临的一大挑战。本论文以廉价易得且富含天然类石墨烯结构的石油沥青为碳源,制备了超高比表面积的沥青基活性炭、高疏水高吸油性能的大孔炭,研究了他们在气体存储和油水分离的应用,另外,本论文还探讨了液相物性对大孔炭材料吸油性能的影响。以乳化沥青为碳源,KOH为活化剂,简便、高效的一步碳化法制备了以微孔结构为主并含有一定量介孔结构的超高比表面积的活性炭。制备的活性炭表现出优越的CO2和CH4吸附能力,样品AC4比表面积最大,高达2736m2/g,并且在高压区内表现出最大气体吸附量,CO2和CH4分别为19.31mmol/g和9.85mmol/g。样品AC2表现出低压区内最大的气体吸附能力,CO2和CH4分别为3.97mmol/g和4.22mmol/g。本论文以廉价易得的石油沥青为碳源,以商品化的密胺海绵为大孔模板,采用一种简单、高效的浸渍-碳化的工艺合成了三种高疏水和高亲油的沥青/密胺海绵基复合大孔炭材料(AMS)。其一,以富含沥青质的脱油沥青DOA为碳源,制得了大孔炭AMS-d;其二,以沥青质含量较低的石油沥青为碳源,制得了大孔炭AMS-a;其三,考虑到有机溶剂的挥发性,本文使用乳化沥青为碳源,使整个制备过程在水相中进行,避免了有机溶剂的使用,绿色、环保的制备了性能优异的大孔炭AMS-e,吸油能力显著高于以上两种材料,吸油量可达自身重量的90~246倍。本论文考察了液相物性对沥青/密胺海绵基复合大孔炭材料吸液性能的影响,结果证明,有机溶剂和表面活性剂都可以有效的降低水溶液的表面张力,降低液滴在海绵炭表面的接触角,实现海绵炭在混合液中由疏水到吸液的改变。而盐溶液的加入可以增加水溶液的表面张力和接触角,不利于海绵炭吸液。因此,海绵炭对含有机溶剂和表面活性剂的污水具有良好的吸收效果,对高盐废水难以发挥作用。
[Abstract]:New porous carbon materials, such as activated carbon with high specific surface area and macroporous carbon with high hydrophobic and high oil absorption properties, have excellent gas adsorption and oil absorption properties due to their unique pore structure, so they are widely used in gas storage / separation. Oil / water separation / oil spill treatment. At present, how to prepare these carbon materials efficiently, environmentally and economically is a major challenge facing the scientific community. In this paper, asphalt-based activated carbon with ultra-high specific surface area and macroporous carbon with high hydrophobic and oil-absorbability were prepared by using petroleum asphalt which is cheap and easy to obtain and rich in natural graphene structure. Their applications in gas storage and oil-water separation were studied. In addition, the effects of liquid phase properties on the oil absorption properties of macroporous carbon materials were also discussed. Using emulsified asphalt as carbon source and Koh as activator, a simple and efficient one-step carbonization method was used to prepare ultrahigh specific surface area activated carbon with microporous structure and a certain amount of mesoporous structure. The prepared activated carbon showed excellent adsorption capacity of CO2 and CH4. The specific surface area of AC4 was the largest, up to 2736 m2 / g, and the maximum gas adsorption capacity of CO2 and CH4 were 19.31mmol/g and 9.85 mmol / g in high pressure region, respectively. The maximum adsorption capacity of CO _ 2 and CH4 was 3.97mmol/g and 4.22 mmol / g, respectively, in the low pressure region of AC2. In this paper, the cheap and easily available petroleum asphalt is used as carbon source, and the commercialized melamine sponge is used as a macroporous template. Three kinds of high hydrophobic and high oleophilic bitumen / melamine sponge based composite macroporous carbon materials (AMS). Were synthesized by high efficiency impregnation and carbonation process. First, macroporous carbon AMS-d; was prepared by using asphaltene rich deoiled asphalt DOA as carbon source. Secondly, macroporous carbon AMS-a; was prepared from asphaltene petroleum asphalt as carbon source, considering the volatility of organic solvents. In this paper, emulsified bitumen is used as carbon source to make the whole preparation process in water phase, avoiding the use of organic solvent, green, environmental protection of the preparation of excellent performance of macroporous carbon AMS-e, oil absorption ability is significantly higher than the above two materials. The oil absorption can reach 90 / 246 times of its own weight. In this paper, the effect of liquid phase properties on the absorbency of asphalt / melamine sponge composite macroporous carbon materials was investigated. The results show that both organic solvents and surfactants can effectively reduce the surface tension of aqueous solution. The contact angle of droplets on the surface of sponge carbon was reduced to change from hydrophobic to absorbent in the mixture. The addition of salt solution can increase the surface tension and contact angle of the solution, which is not conducive to the absorption of carbon sponge. Therefore, sponge carbon has a good absorption effect on wastewater containing organic solvents and surfactants, but it is difficult to play a role in high salt wastewater.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

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