超重力法制备活性氧化镁的研究  

Preparation of active magnesium oxide by a high gravity method

作　　者：周海军[1] 孙宝昌[1] 陈建峰[1] 陈建铭[1] 邵磊[1] 

机构地区：[1]北京化工大学化学工程学院有机无机复合材料国家重点实验室,北京100029

出　　处：《北京化工大学学报（自然科学版）》2012年第5期1-5,共5页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家自然科学基金(20676006/20990221);国家"863"计划(2009AA033301);教育部新世纪优秀人才支持计划(NCET-07-0053)

摘　　要：以超重力机(RPB)为吸收反应装置,用氯化镁溶液耦合吸收NH3和CO2制备前躯体碱式碳酸镁,再经高温煅烧获得活性氧化镁。采用X射线衍射、扫描电镜和碘吸附法等对活性氧化镁进行分析和表征,并考察了煅烧温度对氧化镁形貌和活性的影响。结果表明:在反应温度70℃、超重力机转速1200 r/min、氯化镁初始浓度0.3 mol/L、气体流量364 L/h、NH3体积分数22.1%和CO2体积分数11.3%的条件下,制备出了由纳米片组成的球形碱式碳酸镁颗粒,颗粒直径为3μm,纳米片厚度约为24nm;当煅烧温度为500℃,煅烧时间为2h,制备出了晶粒为7.4nm、吸碘值197.95 mg/g的高活性氧化镁。This work presents an experimental investigation of the synthesis of basic magnesium carbonate （BMC） using the simultaneous absorption of CO2 and NH3 by a MgC12 solution in a rotating packed bed （RPB）. Calcination of the BMC precursor afforded an active magnesium oxide product （AMO）. AMO samples were characterized by XRD, SEM and the iodine adsorption method, and the effects of varying the calcination temperature on the ac- tivity of AMO were studied. The results indicated that BMC spheres having a diameter of 3 μm and composed of nanosheets with a thickness of 24 nm were obtained under the following operating conditions ： a reaction temperature of 70 ℃ , a rotation speed of 1200 r/min, an initial MgC12 concentration of O. 3 mol/L, a volumetric gas flow rate of 364 L/h, an NH3 volume fraction of 22. 1% , and a CO2 volume fraction of 11.3%. AMO with a grain size of 7.4 nm and an iodine adsorption value of 197.95 mg/g was obtained by calcination of the as-prepared BMC at 500 ℃ for 2 h. This work provides an easy route for the mass production of AMO by utilizing CO2 and NH3 emissions.

关 键 词：超重力机 氯化镁 NH3 CO2 碱式碳酸镁 活性氧化镁 

分 类 号：TQ132.2[化学工程—无机化工]