1、第27卷第8期2008年8月电 子 元 件 与 材 料ELECTRONIC COMPONENTS AND MATERIALS、b127 No8Aug2008碳酸镍沉淀过程的研究以及介孔氧化镍的制备刘防，张昭(四川大学化工学院，四川成都610065)摘要：碳酸镍和氧化镍是重要的无机精细化学品，在化学、冶金、电子和能源等领域有广泛的应用。首先从碳酸镍沉淀过程的热力学分析出发，研究阴离子(so：，cr)对碳酸镍沉淀过程的影响。活度系数反映了电解质溶液中阳、阴离子之间和离子与溶剂之间微观作用程度的大小。笔者采用Meissner半经验模型计算了碳酸镍在不同条件下水溶液中的活度系数，并进一步估算了碳酸镍在
2、其中的溶解度大小。估算结果表明，与氯化钠溶液体系相比，碳酸镍在硫酸钠溶液体系中的活度系数较小，因而溶解度较大。为了提高计算置信度。还采用了Brornley模型和Pitzer模型对相应体系的活度系数进行估算，计算结果与Meissner半经验模型的结果非常接近。实验测量了各溶液的表面张力和溶液在碳酸镍表面的润湿角。结果表明，碳酸镍在硫酸钠溶液体系中的固一液界面张力较大，微小晶粒在硫酸钠溶液体系中的溶解度也较大。以上结果表明，碳酸镍在硫酸钠溶液体系中较难析出结晶。在氯化钠溶液体系中则相对容易些。还从结晶动力学方面，研究了上述两种阴离子对碳酸镍沉淀的影响。在相同条件下，反应物为硫酸镍时的过饱和度小于氯
3、化镍。用GlaSstone模型计算了Ni2+和co；。在不同阴离子溶液体系中的扩散系数。结果表明：Ni2+和co；在cr体系中的扩散系数比在so：体系中大，说明其传质更快。soj体系中，碳酸镍的扩散系数较小，过饱和度较小，应用相关结晶动力学公式阐明碳酸镍在其中的成核诱导期更长。因此，碳酸镍在soi体系中的成核和生长速率都小于Cl一体系。结晶动力学实验结果表明，碳酸镍沉淀反应是一级反应，反应速率常数约为O02IIlin-l。在上述理论的指导下，对碳酸镍沉淀工艺进行了研究。考察了镍盐选择、加料方式、pH值控制、反应温度和陈化条件对碳酸镍产物纯度、粒度、形貌和转化率等方面的影响。以工业电解镍液为镍源
4、，碳酸钠为沉淀剂，在最佳反应条件下可以得到镍含量5l左右，平均粒径约17 LLm的碱式碳酸镍，镍的转化率可达995。以创新的洗涤一干燥一二次洗涤一二次干燥过程对碳酸镍沉淀进行深度除杂，产品碳酸镍中钠、Cl-的质量分数均不超过ool，w(so：。)不超过o1。以stem双电层模型阐述了Na+、cl一在碳酸镍固体表面吸附的机理。采用材料计算机模拟技术，从分子原子尺度研究了soi。、cl一两种阴离子在碳酸镍表面的影响情况。首先对晶胞结构进行优化，模拟得到的碳酸镍晶胞参数与文献值非常接近。创建碳酸镍晶面，对5个主要的晶面进行模拟，分别是(104)、(100)、(110)、(001)和(101)晶面。s
5、o：。与表面co；。发生取代作用，在表面形成稳定的结构。cl一在表面吸附，对表面的影响不如s042-那样强烈。soi、cl一杂质阴离子的引入使碳酸镍各晶面的生长速率明显下降，其中，soj作用表面的生长速率低于cl作用表面。对于干燥、水化、阴离子作用的各情况下的碳酸镍晶体，(104)晶面均是平衡形貌的主要显露面。最后，以制备高纯度碳酸镍的工艺为基础，通过在镍源中添加模板剂制各前驱体，然后加热煅烧制备了具有介孔结构的氧化镍。实验结果表明：以阴离子型表面活性剂SDS为模板剂的氧化镍产物的比表面积，远大于以阳离子型表面活性剂CTAB和非离子型表面活性剂ODA为模板剂的产物，结合电渗析现象，认为无机前驱
6、物与模板剂SDS之间以静电力相互作用。前驱体经煅烧后，产物中基本无表面活性剂残留。在较低的模板剂用量(，(SDS：Ni)小于01：10)条件下，得到了比表面积大于200 m2矿1、具有H3型介孔结构的氧化镍，孔径分布主要在210 nm，且具有较好的热稳定性。关键词：无机非金属材料：碳酸镍；理论分析；工艺研究；计算机模拟；介孔氧化镍中图分类号：TQll06 文献标识码：A 文章编号：10012028(2008)08007202收稿日期：20080617 通讯作者：刘防基金项目：国家自然科学基金资助项目(ND50474071)作者简介：张昭(1947一)。女广东梅县人，教授博士，主要从事材料新工艺
7、与功能材料的研究。Tcl：(028)85405322：Bmail：zzhangscueducn：刘防(198l一)，女四川鄙江堰人，懈士研究方向为化工新技术与新工艺开发。Tel：(028)85405213：Email：wbomsunxxyahoocomIcn。万方数据第27卷第8期 刘叻等：碳酸镍沉淀过程的研究以及介孔氧化镍的制备 73Study on the precipitation process of nickel carbonate and synthesis ofmesoporous nickel 0xideLIU Fang，ZHANG Zhao(School of Chemica
8、l Engineering，Sichu锄UniVersi吼Chengdu 610065，China)Abstract：Nickel ca内onate and nickel oxide are important inor2anic 6ne chernjcals，widely used in chenlical，metallu唱ical，electrollic a11d ene唱y sources industriesThe research was beginning wim studying the ef!fects of anions on precipitation process of
9、 nickel carbonateActi、，i哆coemcient shows也e eff色ct size of tlle IIlicrocoslic ef!Iects between ions and solventMeissners senliempirical model was aplplied to calculate the average activity coemcients of nickel carbonate in different electrolytesOlutions at dif诧rent conditiOnsAnd the conditional s01ub
10、ilitv of nickel carbonatc was also calculatedThe calculatedresults show that activity coef!ficients 0f Ni003 in sodium sulphate solutions are less than that in sodium chloridesolutions，aJld me solubilities in sodium sulphate solutions are largerTb improve me confidence of the calculations，BroInleys
11、aIld Pitzers models were alsO applied t0 calculate activity coemcientsThe calculation results Of BrornleysaJld Pitzers models are very close to Meissners resultsAnd men experiments were c硎ed out to rneasure the suracetensions，and contact柚gles of solutions on Ni003 suaceAccordin2 to me experiment res
12、ults，t11e solid1iquidinterface tension between NiC03 and sodium sulphate s01ution is larger than仇at between NiC03 and sodium chloridesolutionAnd me tiny crystal NiC03 has laLrger solubility in sodium sulphate solutionswhich indicates thatc珂stallization of NiC03 in sodium sulphate solution is more di
13、fficult than in sodium chIoride solutionThe innuence of SOi。 a11d Cr on precipitation and crysta儿ization process of NiC03 was also studied based onc口stal dynamicsThe supersaturations at diff色fem initiaJ concentration of reaction system were comparedDiffusioncoefFicientS of ions werc described by Gla
14、sstones modelThe djffusion coemcients of Ni“and COi。 in chloridesolutions are larger than thOse in sulphate solutionsIn sulphate solutions，the diffusion coefficients and supersaturationare both less，therefore nucleation and growth rates are more slowlyFurthe加ore，the experiments of crystallizationdyn
15、anlics show that the reaction of nickel carbonate precipitation is a first order reaction while the reaction ratec三nstant is about o02 min Based on ttle theoretical analysis above，technology process of nickel carbonate precipitation was studiedsubsequentI yThe effects Of nickel salt，f色eding mode，con
16、trDlling pH，reaction temperature and agin2 condition onpurity，particle size，appe啪nce of product and recovery ratio of nickel were investi2atedThen usin2 industrial nickelelectrolyte solutiOn and sodium carbonate as the raw materials，nickel carbonate product with nickel content Of about5 l， average p
17、anicle size 0f 17 Um was prepared at optimal conditions，and the recovery mtio of nickel is around995 Nickel carbonate with high purity was obtained via an innovative impurity removal process calledwashdryrewashredry processThe sodium and chlorine qualitative contents of me nickel carbonate purified
18、by theinnovative method are both less than 00 land the sulphate content is no more than 01The mechanism of sodiumand chlodne adsorption onto nickel c2urbonates surface was discussed，using Stems model of electric double laverMoreover computational simulation technology was applied to investigate on h
19、ow anions af!fect me crystallizationof NiC03 at atom scaleThe lattice stlllcture was relaxed before establishing crystal surfacesTlhe computational unitcell parameters are Ve巧close to the expenmental dataFive majn surlaces were studied，iethe(104)，(100)，(1 10)，(001)and(101)suacesS0i substitutes the C
20、O；。on the outmost layerCl-adsorbs onto the surfaces and hasrelative weaker interaction witll t11e surfacesCompared with only hydrated suaces，the growth rates of defectedhydrated surfaces significantly decrease，especially for sojdefected onesThe(104)surface is the most stablesurface and is mainly exp
21、ressed in the equilibrium morphology of the resultin2 cn，stalFinally，based on the study of nickel carbonate synthesis，nickel oxide with mesoporous structure was prepared bVadding template into the nickel souIe and calcinatjonThe eff色cts of types of suIfactant，dosa2e of surfactantcalcinanon temperatu
22、re and calcination dme On pore structure and specific suace area of nickel oxide wereinvestigatedThe results show that the surface area of me nickel oxide prep删by sodium dodecyl sulphate(SDS，anion suactant)is much la唱er man those of which prepared by CIAB and octadecylamineIt is su譬gested t11at t11e
23、ino略aIlic species，basic nickel carbonate，is interacted wit量1 the template，SDS，by electrostatic attraction forceTheprecurSor hardly has any surlactant residue after calcinationNickel oxide with hjgh specinc suace area(200m g_1)is synthesized by adding low amount of template at the mole ratio of SDS：N
24、i less than O1：10The nickeloxide has H3 type hysteresis and me pore size distribution mainly ranges from 2 nm to 1 O nmAnd it has good themalstabili吼Key words： nonmeta】lic inorganic material； nickel carbonate： theoretic analysis； techn0109V reseaurch；computational simulation；mesoporous nickel oxide(
25、编辑：朱盈权)万方数据碳酸镍沉淀过程的研究以及介孔氧化镍的制备作者： 刘昉， 张昭， LIU Fang， ZHANG Zhao作者单位： 四川大学,化工学院,四川,成都,610065刊名： 电子元件与材料英文刊名： ELECTRONIC COMPONENTS & MATERIALS年，卷(期)： 2008,27(8)本文读者也读过(3条)1. 刘昉.Nora H.de Leeuw.张昭.LIU Fang.Nora H.de Leeuw.ZHANG Zhao 计算机模拟阴离子对碳酸镍结晶过程的影响期刊论文-无机化学学报2009,25(10)2. 吕文广 高纯碱式碳酸镍的综述及其生产会议论文-20093. 陈野.刘良.张尊波.向琪.CHEN Ye.LIU Liang.ZHANG Zun-bo.XIANG Qi 并流沉淀法合成氧化镍及其电容性能期刊论文-精细化工2008,25(5)本文链接：http:/
