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101.
针对高炉炉渣中Al2O3含量(质量分数)偏高导致炉渣黏度增大、流动性变差、脱硫能力下降的问题,利用双层石墨坩埚模拟铁液滴下穿过炉渣的过程,探究了R[w(CaO)/w(SiO2)],w(MgO)/w(Al2O3)和w(Al2O3)对高Al2O3型CaO-SiO2-MgO-Al2O3四元高炉渣系脱硫能力的影响.当w(MgO)/w(Al2O3)=0.50,w(Al2O3)=20%时,R由1.05提高到1.35,炉渣的脱硫能力增强;当w(Al2O3)=20%,R=1.30时,w(MgO)/w(Al2O3)由0.25提高到0.55,炉渣的脱硫能力增强;当w(MgO)/w(Al2O3)=0.40,R=1.30时,w(Al2O3)由12%提高到20%,炉渣的脱硫能力下降. 相似文献
102.
采用过渡金属对2.5%Mg O/ZSM-5催化剂进行负载改性,考察其苯-甲醇烷基化性能,结果表明,Ni和Fe改性催化剂因改性后弱酸量大幅增加,苯转化率提高,分别为56.6%和55.8%;W和Mn改性催化剂二甲苯选择性较高,约为35%;与其他改性催化剂相比,Co和Mo改性催化剂上的苯转化率和二甲苯选择性没有明显优势。选择改性效果较好的双金属催化剂进行苯-甲醇烷基化高空速(15 h-1)长时间运转实验,催化剂初始活性均大于57%,反应20 h时,苯转化率约50%,20 h后烷基化活性迅速下降,是由于催化剂积炭失活所致。 相似文献
103.
The effect of MgO on the composition and properties of alite-sulphoaluminate cement clinker with commercial-grade raw materials such as limestone, clay, gypsum and fly ash as starting materials has been investigated in order to confirm results previously obtained with pure raw materials. The experiment results confirm that the addition of MgO at about 2-5% can improve the burnability of raw meal, promote the absorption of free lime and the formation of C3S and C4A3S¯. In addition, it is shown that this can also increase the strength development of the cement and shorten the setting time. When the content of MgO reaches about 8%, the strength of the cement decreases slightly and the setting time is extended. 相似文献
104.
Catalyst performance of NiO–MgO solid solution catalysts for methane reforming with CO2 and H2O in the presence of oxygen using fluidized and fixed bed reactors under atmospheric and pressurized conditions was investigated. Especially, methane and CO2 conversion in the fluidized bed reactor in methane reforming with CO2 and O2 was higher than those in the fixed bed reactor over Ni0.15Mg0.85O catalyst under 1.0 MPa. In contrast, conversion levels in the fluidized and fixed bed reactor were almost the same over MgO-supported Ni and Pt catalysts. It is suggested that the promoting effect of catalyst fluidization on the activity is related to the catalyst reducibility. On a catalyst with suitable reducibility, the oxidized and deactivated catalyst can be reduced with the produced syngas and the reforming activity regenerates in the fluidized bed reactor during the catalyst fluidization. In addition, the catalyst fluidization inhibited the carbon deposition. 相似文献
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Ping Shen Lifeng Zhang Jianxun Fu Hao Zhou Yi Wang Limei Cheng 《Ceramics International》2019,45(9):11287-11295
In the present study, the wettability between liquid iron with two different Al contents and MgOAl2O3 binary substrates was studied in reducing atmosphere. The contact angles between liquid iron with 18?ppm Al and MgO, MgO·Al2O3, Al2O3 were 133.5°, 113.7°, 126.9° respectively. With the variation of the substrate composition, the contact angles for the intermediate binary phases of the three components (MgO, MgO·Al2O3, Al2O3) obeyed the Cassie theory. In the experiment using iron with 370?ppm Al, all the contact angles were higher than that using low Al-containing iron. The surface of the iron drop was covered with an oxide layer, which mainly consisted of many small particles. With the variation of the substrate gradually from MgO to Al2O3, the composition of the oxide layer changed from MgO·Al2O3 to CaOAl2O3. The formation of the oxide layer prevented the spreading of liquid iron, leading to the increase of the contact angle. 相似文献
108.
109.
The influence of MgO on the formation of Ca3SiO5 and 3CaO·3Al2O3·CaSO4 minerals in alite-sulphoaluminate cement is reported in this paper. The results show that adding a suitable amount of MgO can lower the clinkering temperature, promote the formation of Ca3SiO5 and 3CaO·3Al2O3·CaSO4 minerals, and help in the coexistence of the two minerals in the clinker. MgO may obviously decrease the formation of Ca3Al2O6, and increase the SiO2 content incorporated into the interstitial phase. 相似文献
110.