| 摘要: |
| 为研究水杨酸甲醇溶液(SAM)对水泥熟料中硅酸盐矿物的溶解反应机理，采用足量SAM来溶解水泥熟料的晶体产物并培养单晶体，经X射线衍射（XRD）单晶结构分析后，确定所培养的单晶体为水杨酸钙(C14H10O4Ca·2H2O).水杨酸钙属于单斜晶系的非心Cc空间群，在不对称单元中Ca与水杨酸中6个羧基氧原子和2个水分子氧原子形成了八配位的八面体结构.用红外光谱（FTIR）检测到了该晶体在3487cm-1处的结合水和在3519cm-1处羧基的—OH伸缩振动峰消失，羰基伸缩振动峰从1656cm-1迁移至1548cm-1.该晶体的13C NMR谱中苯环C基本未变化，因羧基的—OH参与化合反应，C7位移δ从17180转移至17609；1H NMR谱检测到了该晶体在δ=49500处的结合水.试验表明：铝酸钙和铁铝酸钙在SAM溶液中是稳定相，水杨酸中羧基与硅酸盐矿物中CaO化合生成了易溶于甲醇的水杨酸钙；水杨酸与硅酸盐矿物反应的化学计量关系是2摩尔水杨酸结合1摩尔CaO，当两者摩尔比小于2时，生成的晶体不溶于甲醇，不能用于熟料矿物分离. |
| 关键词: 硅酸盐矿物 水泥熟料 水杨酸 水杨酸钙 选择性溶解 |
| DOI：103969/j.issn.1007 9629201902004 |
| 分类号: |
| 基金项目:陕西省自然科学基础研究计划项目(2016JM5010)；山西省科技创新项目(2013101038) |
|
| Dissolution Reaction Mechanism of Silicate Minerals in Portland Cement Clinker |
|
HOU Xinkai1, HUANG Ruitao1, LIU Wen2, GUO Haitao1, WANG Dan1
|
|
1.College of Materials Science and Engineering, Xian University of Architecture and Technology, Xian 710055, China;2.School of Science, Xian University of Architecture and Technology, Xian 710055, China
|
| Abstract: |
| The mechanism of dissolution reaction of cement clinker silicate minerals by salicylic acid methanol(SAM) has been investigated. Crystal product made from dissolution of cement clinker by mixing it with sufficient SAM was extracted and cultured. XRD single crystal structure analysis was used to identify the monocrystalline product as calcium salicylate(C14H10O4Ca·2H2O), which is classified as the noncentral Cc spatial group of monoclinic crystal system. In the asymmetric unit, Ca was found to be coordinated with six carboxylate O from the salicylic acid and two water molecules O, giving rise to the formation of an eight coordinate octahedral structure. The FTIR spectrum of the crystal showed that a peak at 3487cm-1 appeared to correspond to boned water molecules, and the peak at 3 519cm-1 disappeared, indicating the disappearance of —OH stretching vibration of the carboxyl group. The peak at 1656cm-1 shifted to lower frequency at 1548cm-1 representing the carbonyl CO stretching vibration. In the 13C NMR spectrum of the crystal, the benzene ring C δ was largely the same as that of salicylic acid. The C7 δ shifted from 17180 to 17609 because the —OH of the carboxyl group takes part in the combination reaction. In 1H NMR spectroscopy the crystal bound water arises at δ=49500 The results have shown that calcium aluminate and calcium ferroalumnates are inert phases in SAM. Calcium salicylate is here synthesized using the carboxyl groups of salicylic acid and CaO of silicate minerals, then dissolved in methanol. The stoichiometric ratio of salicylic acid to CaO from silicate minerals is 2∶1 When the stoichiometric ratio fell below this value, the product became insoluble in methanol so the case is not adopted for clinker mineral separation. |
| Key words: silicate mineral cement clinker salicylic acid calcium salicylate selective dissolution |
