摘要
以13X分子筛为载体,采用液相离子交换法制备了Cu+-13X吸附剂和负载碱土金属元素Mg的Mg2+/Cu+-13X吸附剂,并利用XRD,XRF,ESEM和激光拉曼光谱仪(HR-800)等手段对所制备的吸附剂进行了表征。以含有噻吩和2-乙基噻吩的正己烷溶液为模拟燃料油,分别从静态吸附、吸附动力学两方面研究了两种吸附剂的脱硫性能,采用Langmuir模型和竞争吸附的Langmuir模型对单、双组分硫化物的静态吸附平衡数据进行拟合;采用Crank单孔扩散模型对吸附动力学数据进行拟合。结果表明,当Mg2+/Cu+-13X吸附剂中Mg的质量分数为3.35%时,吸附性能最佳;实验数据与模型吻合均很好,计算得到了Mg2+/Cu+-13X吸附剂对噻吩和2-乙基噻吩单组分的最大吸附量分别为140.7mg?g?1和183.8 mg?g?1,较Cu+-13X吸附剂对噻吩和2-乙基噻吩单组分的最大吸附量(130.2 mg?g?1和173.6 mg?g?1)分别提高了8.1%和5.9%,Mg2+/Cu+-13X双金属吸附剂的脱硫效果明显好于Cu+-13X吸附剂;负载的Mg2+作为一种助剂,使分子筛形貌分布更加均匀规整,并且增加了吸附剂的Lewis酸含量,使其还原性增强,吸附性能提高。
Adsorbents involving modified 13X zeolite with Cu＋or Mg2＋/Cu＋cations were prepared by liquid phase ion-exchange method. The properties of these adsorbents were characterized by means of XRD, XRF, ESEM and Horiba Labram HR-800. The adsorption desulfurization performances of Cu＋-13X and Mg2＋/Cu＋-13X were investigated by static adsorption equilibrium and their adsorption kinetics were tested by using thiophene and 2-ethylthiophene in the n-hexane as model transportation fuels. The static adsorption equilibrium data of the single component and bi-component adsorption systems were fitted by Langmuir model and competitive adsorption Langmuir model; the kinetics test data were fitted by Crank diffusion model. The experimental results show that the best adsorption desulfurization performance can be obtained by Mg2＋/Cu＋-13X with 3.35%of the Mg mass fraction;the experimental data were fitted well by the above models, the maximum sulfur adsorbing capacities of Mg2＋/Cu＋-13X for thiophene and 2-ethylthiophene are 140.7mg·g-1 and 183.8 mg·g-1, respectively. Adding alkaline earth metal element Mg in Cu＋-13X leads to 8.1% and 5.9%increase of the original thiophone and 2-ethylthiophene adsorption quantity of Cu＋-13X（130.2 mg·g-1 and 173.6 mg·g-1）, separately. The adsorption desulfurization property of Mg2＋/Cu＋-13X is apparently much better than that of Cu＋-13X, the presence of Mg2＋as a co-catalyst makes the morphology of 13X zeolite well-distributed and increases the Lewis acidity content of the adsorbent which enhances the reduction ability of the adsorbent,and finally leads to the improvement of its adsorption capacity.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2014年第1期183-189,共7页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金(21176118)
关键词
碱土金属元素
Cu+-13X分子筛
吸附脱硫
噻吩
2-乙基噻吩
alkaline earth metal element
Cu＋-13X molecular sieve
adsorptive desulfurization
thiophene
2-ethylthiophene
