Reactive Adsorption of Thiophene on ZnNi/Diatomite-Pseudo-Boehmite Adsorbents

The thiophene removal ability of the synthesized ZnNi/diatomite-pseudo-boehmite adsorbent was tested in a lab- scale fixed-bed reaction system. X-ray diffractograms （XRD） were used to characterize the adsorbent samples. The effects of Zn/Ni molar ratio, various model fuels and regeneration patterns on the RADS tests were studied. The adsorption mecha- nism was investigated by XRD and MS analyses. The results indicted that thiophene in the model fuel was first decomposed on the surface Ni of the adsorbent to form Ni3S2 while the hydrocarbon portion of the molecule was released back into the process stream, followed by reduction of Ni3S2 to form H2S in the presence of H2, and then HzS is stored in the adsorbent accompanied by the conversion of ZnO into ZnS.

Reactive Adsorption of Thiophene Using a NiZnO-Based Adsorbent

The thiophene removal ability of the synthesized NiZnO-based adsorbent was tested in a lab-scale fixed-bed system. The X-ray diffractometer (XRD) and the temperature-programmed reduction (H2-TPR) instrument were used to characterize the samples. The XRD and TPR results showed that there existed stronger synergetic effect between ZnO and NiO to form well-dispersed adsorbent particles when the Zn/Ni molar ratio in adsorbent was 0.4, and that the optimum temperature for reduction of the NiZnO-based adsorbent was approximately in the range of 350℃—400℃. In addition, the effects of reaction temperature, and reaction pressure on the reactive adsorption desulfurization tests were studied.

Reactive adsorption desulfurization over a Ni/ZnO adsorbent prepared by homogeneous precipitation

A high-performance Ni/ZnO adsorbent was prepared by homogeneous precipitation using urea hydro- lysis and characterized by N2 adsorption-desorption, X-ray diffraction （XRD）, and scanning electron microscope （SEM）. The adsorbent was applied to the deep desulfur- ization of gasoline and showed a high breakthrough sulful capacity and a remarkably high volume hourly space velocity. The effects of coexisting olefins in gasoline as well as adsorptive conditions on the adsorptive perfor- mance were examined. It was found that olefins in gasoline had a slightly inhibiting effect on the desulfurization performance of the adsorbent. The optimum conditions were 673 K, 1.0 Mpa with a volume hourly space velocity of 60h^-1. Under the optimum conditions, ultralow sulfur gasoline could be produced and the breakthrough sulfur capacity of the adsorbent was 360 mg-s/g-sorb for the model gasoline.

用镍系非晶态合金脱除苯中硫的研究

应用程序升温吸附脱附法对噻吩在镍系非晶态合金上的吸附和脱附研究表明 ,常温下 ,噻吩在非晶态合金表面发生物理吸附和化学吸附。物理吸附的噻吩可以脱附 ,而化学吸附的噻吩在非晶态合金表面被活化 ,发生氢解反应 ,C—S键断裂 ,硫留在镍系非晶态合金上 ,释放出烃类。对以镍系非晶态合金为吸附剂的磁稳定床中对苯脱硫过程进行了研究 ,研究了各种操作参数对脱硫效果的影响。实验结果表明 ,在磁稳定床中采用吸附脱硫 ,可使苯中硫的质量分数从 2 μg/g降至 0 0 2 μg/g以下。

不同载体的镍基氧化锌对噻吩的吸附脱除性能

采用混捏法制备了以金属氧化物、黏土及分子筛为载体的三类镍基氧化锌吸附剂,采用FT-IR等分析手段进行表征,探讨了其物化性能的差异,并利用微型固定床反应器考察了上述吸附剂对噻吩的吸附脱除性能。结果表明,不同吸附剂对噻吩的吸附效果不同,黏土载体的吸附剂脱硫性能高于金属氧化物载体的脱硫性能,吸附剂的脱硫活性顺序依次为cay-sorb>diatomite-sorb>Al-sorb>Ti-sorb。利用FT-IR对吸附剂的表面酸性进行了表征。结果表明,吸附剂的脱硫性能与其总L酸量有关,总L酸量高的吸附剂脱硫效果较好。分子筛载体吸附剂的脱硫活性顺序依次为MCM-22-sorb>HY-sorb≥Hβ-sorb>H-mordenite-sorb>HZSM-5-sorb。通过比较分子筛载体的孔道结构表明,分子筛载体孔径大小是影响吸附剂脱硫性能的主要因素。

Co-BTC脱除噻吩性能研究

基于溶剂热法合成出金属有机骨架材料Co-BTC,通过XRD、IR表征其结构。采用固定床吸附穿透实验,考察了不同的空速条件及溶解水对Co-BTC吸附分离噻吩的影响,并用甲苯溶剂洗涤进行吸附剂再生。结果表明,Co-BTC对模型油中噻吩的穿透容量及饱和吸附量分别为0.98%,2.05%(wt);Co-BTC在含溶解水和纯模型油中硫的饱和容量分别是1.50%,2.05%,饱和吸附容量降低了27%,运用分子筛分层填装吸附柱技术能将Co-BTC的饱和吸附容量提高到2.02%;再生的吸附剂对模型油中噻吩硫的饱和吸附容量为2.02%,再生率达到99%。

Ni-Zn复合氧化物用于反应吸附脱除噻吩

采用均匀共沉淀法制备了Ni-Zn复合氧化物吸附剂,并在固定床上考察了预还原、吸附条件、模拟油的不同组分对其吸附脱硫性能的影响。结果表明,还原态的Ni是吸附剂的主要活性成分,吸附反应最适宜的温度和压力分别为673K、1.0MPa,模拟油中的烯烃组分对吸附剂脱硫性能的影响比芳烃的影响大。吸附剂在温度673K、压力1.0MPa、液时空速60h-1、氢气与模拟油的体积比为200(氢气体积为标准状态下的体积)时对含硫质量浓度100mg/L的模拟油A的硫容为360mg/g。噻吩首先在Ni原子上进行氢解生成H2S,然后H2S快速与ZnO结合生成ZnS。此外该吸附剂对原料有很好的适应性,并具有很好的再生性能。

金属有机骨架化合物MOF-14的脱硫效果研究

采用水热法合成出金属有机骨架化合物MOF-14,基于固定床动态吸附实验,考察了室温下MOF-14对模型油中噻吩及苯并噻吩的脱除效果,并经溶剂甲苯洗涤对吸附剂进行再生。结果表明,MOF-14对模型油中噻吩和苯并噻吩的饱和吸附容量分别为2.02%,0.53%;吸附剂再生后对模型油中苯并噻吩的吸附饱和容量为0.53%,再生率达到100%。

棒状Ni/CuO-ZnO的制备及其反应吸附脱硫性能研究

采用水热合成法制备了棒状CuO-ZnO复合氧化物,采用等体积浸渍法制备了Ni/CuO-ZnO吸附剂,采用TG,SEM,XRD,BET方法进行了表征。在固定床反应器中进行了吸附剂的反应吸附脱硫性能评价。结果表明:复合氧化物经500℃焙烧制备的CuO-ZnO复合氧化物呈棒状结构;Cu的掺杂有效改进了反应吸附剂的脱硫性能,Cu的最佳掺杂量(w)为10%,掺杂Cu后脱硫率较Ni/ZnO平均脱硫率提高17.4百分点,且能延长有效脱硫时间,吸附剂在45h左右仍能保持较高的脱硫活性。

负载骨架镍吸附剂用于苯深度吸附脱硫的研究

以镍铝合金粉及拟薄水铝石为原料制备了用于苯深度脱硫的负载型骨架镍吸附剂,采用X射线衍射(XRD)、氢程序升温还原(H_(2)-TPR)、扫描电镜(SEM)等对吸附剂的物化性质进行表征分析,并对吸附剂深度脱除苯中微量噻吩的性能进行评价。结果表明,负载型骨架镍吸附剂主要通过氧化铝负载的骨架活性金属镍与苯中噻吩硫通过化学吸附作用达到选择吸附脱硫的目的,在吸附温度150℃、吸附压力1.0 MPa、苯中噻吩浓度为100μg·g^(-1)、进料液时空速为2 h^(-1)的条件下,吸附剂对噻吩的穿透吸附容量31.09 mg·g^(-1),饱和吸附容量32.44 mg·g^(-1),吸附脱硫产物苯中噻吩含量检不出,表现出吸附剂具有对苯中噻吩硫化物良好的选择吸附脱硫性能。