基于钒取代的Keggin型钼磷酸的石墨烯杂化材料及催化氧化脱硫活性研究
发布时间：2018-09-03 09:10
【摘要】：本论文中采用两种方法制备了基于钒取代Keggin型钼磷酸(H_5PV_2Mo_(10)O_(40)简称:POVM)的石墨烯杂化材料,系统研究了该材料在燃料油脱硫反应中的催化活性。主要内容及创新性研究如下:1.利用乙二胺还原氧化石墨烯得到胺功能化的石墨烯杂化物,将其浸泡在多酸的水溶液中制备了多酸石墨烯杂化材料(POVM-rGO-1)。在材料的合成过程中,通过调节乙二胺和多酸的用量,可以控制材料表面胺基的数量以及多酸的担载量。经实验发现,将50mgGO分散在10mL水中,加入0.1mL乙二胺还原,而后将rGO浸泡在20mg/mL,10mL的多酸水溶液中可以得到催化效果最好的材料(POVM-rGO-1a)。虽然催化剂可以较好的分散在油相中,但是在加入过氧化氢之后,催化剂出现团聚现象。这可能有两方面原因,一方面,催化剂表面的胺基基团和过氧化氢之间形成氢键;另一方面,多酸具有极强的亲水性,而过氧化氢溶液中含有大量水。这两种原因导致催化剂更容易聚集在过氧化氢相,而过氧化氢相的强极性使其不能在油相中良好的分散,因此也破坏了催化剂在油相中的分散。基于此种情况,在体系中加入了萃取剂乙腈,形成了萃取-催化氧化脱硫体系。乙腈可以从油相中萃取一部分的硫化物,并且过氧化氢和催化剂都更容易分散在极性较强的乙腈相中。当乙腈中的硫化物被氧化为相应的砜时,随着搅拌的过程,会再次萃取一部分硫化物,直至达到完全脱硫。10mL,500ppm的模拟油中加入5m L的乙腈,0.05g催化剂(POVM-rGO-1a),0.5mL 30%过氧化氢,在60℃油浴中搅拌30min转化率达到100%。催化剂可以使用离心方法分离,重复使用5次依然保持较高的活性。2.采用光还原的方法,利用乙二醇还原POVM得到的杂多蓝来还原氧化石墨烯,得到材料(POVM-rGO-2)。以氧气为氧化剂,异丁醛为牺牲试剂,80℃时,5h,0.1g的POVM-rGO-2可以催化10mL的500ppm的模拟油实现完全脱硫。
[Abstract]:In this paper, graphene hybrid materials based on vanadium substituted Keggin molybdenum phosphoric acid (HAP5PV2Mo10 O40) were prepared and their catalytic activity in desulfurization of fuel oil was systematically studied. The main contents and innovative research are as follows: 1. The graphene hybrid material (POVM-rGO-1) was prepared by using ethylenediamine to reduce graphene oxide to amine-functionalized graphene hybrid material, which was immersed in aqueous solution of polyacid. The amount of amino groups on the surface and the loading of polyacids can be controlled by adjusting the amount of ethylenediamine and polyacid during the synthesis of the materials. It was found that the best catalytic material (POVM-rGO-1a) could be obtained by dispersing 50mgGO in 10mL water adding 0.1mL ethylenediamine and then immersing rGO in 20mg / mL 10 mL polyacid solution. Although the catalyst can be well dispersed in the oil phase, but after the addition of hydrogen peroxide, the catalyst appears agglomeration. There may be two reasons for this: on the one hand, hydrogen bonds are formed between the amine groups on the surface of the catalyst and hydrogen peroxide; on the other hand, polyacids have a strong hydrophilicity, and hydrogen peroxide solution contains a lot of water. These two reasons cause the catalyst to concentrate in the hydrogen peroxide phase more easily, and the strong polarity of the hydrogen peroxide phase makes it can not be well dispersed in the oil phase, thus destroying the dispersion of the catalyst in the oil phase. In this case, the extractant acetonitrile was added to the system to form an extraction-catalytic oxidation desulfurization system. Acetonitrile can extract part of sulfides from oil phase, and hydrogen peroxide and catalyst are more easily dispersed in highly polar acetonitrile phase. When the sulfides in acetonitrile are oxidized to corresponding sulfone, some sulfides will be extracted again with the stirring process, until the amount of acetonitrile 0.05g catalyst (POVM-rGO-1a) of 0.5 mL 30% hydrogen peroxide is added to the simulated oil of complete desulphurization. The conversion rate of 30min agitated in 60 鈩，
本文编号：2219532
[Abstract]:In this paper, graphene hybrid materials based on vanadium substituted Keggin molybdenum phosphoric acid (HAP5PV2Mo10 O40) were prepared and their catalytic activity in desulfurization of fuel oil was systematically studied. The main contents and innovative research are as follows: 1. The graphene hybrid material (POVM-rGO-1) was prepared by using ethylenediamine to reduce graphene oxide to amine-functionalized graphene hybrid material, which was immersed in aqueous solution of polyacid. The amount of amino groups on the surface and the loading of polyacids can be controlled by adjusting the amount of ethylenediamine and polyacid during the synthesis of the materials. It was found that the best catalytic material (POVM-rGO-1a) could be obtained by dispersing 50mgGO in 10mL water adding 0.1mL ethylenediamine and then immersing rGO in 20mg / mL 10 mL polyacid solution. Although the catalyst can be well dispersed in the oil phase, but after the addition of hydrogen peroxide, the catalyst appears agglomeration. There may be two reasons for this: on the one hand, hydrogen bonds are formed between the amine groups on the surface of the catalyst and hydrogen peroxide; on the other hand, polyacids have a strong hydrophilicity, and hydrogen peroxide solution contains a lot of water. These two reasons cause the catalyst to concentrate in the hydrogen peroxide phase more easily, and the strong polarity of the hydrogen peroxide phase makes it can not be well dispersed in the oil phase, thus destroying the dispersion of the catalyst in the oil phase. In this case, the extractant acetonitrile was added to the system to form an extraction-catalytic oxidation desulfurization system. Acetonitrile can extract part of sulfides from oil phase, and hydrogen peroxide and catalyst are more easily dispersed in highly polar acetonitrile phase. When the sulfides in acetonitrile are oxidized to corresponding sulfone, some sulfides will be extracted again with the stirring process, until the amount of acetonitrile 0.05g catalyst (POVM-rGO-1a) of 0.5 mL 30% hydrogen peroxide is added to the simulated oil of complete desulphurization. The conversion rate of 30min agitated in 60 鈩，
本文编号：2219532
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