【作者】 陈全莉；

【导师】 陈敬中； 袁心强；

【作者基本信息】 中国地质大学 ， 宝石学， 2009， 博士

【摘要】 绿松石是一种含水的铜铝磷酸盐类矿物，化学式为CuAl₆[PO₄]₄（OH）₈·4H₂O，属三斜晶系，因其形状如松果、颜色多呈蓝绿色而得名，是深受古今中外人们喜爱的传统名贵玉石。近些年来，绿松石新矿床的发现和开采远远低于社会的需求量，导致国内外珠宝市场上优质绿松石原矿的供需矛盾日趋锐化，绿松石原料价格近五年持续暴涨。受绿松石复杂的矿床成矿地质条件制约，绿松石原矿品质大部分欠佳，普遍存在颜色不佳、偏浅或无色，裂隙和孔隙度较发育等问题，多数难以达到优质品级，因而失去它应有的价值。由于绿松石矿山开采技术和加工装备落后，资源利用率低，加之绿松石加工业的无序竞争，导致绿松石资源大量浪费，每年数吨开采后的绿松石细小矿渣和加工后的绿松石余渣粉料（统称为绿松石废弃料）被丢弃，绿松石资源的综合再生利用亟待加强。此外，传统的人工注塑处理绿松石产品内部充填有大量的有机高分子聚合物，导致其化学成分、结构、物理光学性质等宝石学特性与天然绿松石差异甚大，且该方法仅限于较大的绿松石单体原料，对小颗粒的绿松石废弃料尚难以具体实施。因此，研究绿松石废弃料化废为利，提高色浅质差绿松石品级，缓解绿松石供不应求的问题具有非常重要的意义。本文重点选取小颗粒的绿松石废弃原料和绿松石次级单体原料为研究对象，遴选与绿松石化学成分相近的无机结合剂Al（H₂PO₄）₃溶液及相关辅助材料，采用不同的化学配方与试验条件，通过浸胶充填和压制再造的化学聚合方法对绿松石次级单体原料和小颗粒废弃料进行人工优化处理和改善，达到提高绿松石废弃料的单体尺度和改善绿松石次级原料质量的目的，使其宝石学特征，工艺和力学性质得到明显改善，借以为我国绿松石资源的综合再生利用和优化处理提供科学依据。通过本文研究主要取得了如下结论：1．以绿松石储量最优的湖北省竹山县秦古镇产出的绿松石为重点研究对象，以竹山县喇叭山、郧县以及安徽马鞍山地区产出的绿松石为比对研究对象，对天然绿松石的产出地质特征、化学成分，显微结构、呈色机理等进行了研究和探讨。结果表明：（1）绿松石颜色除与致色元素Fe³⁺、Cu²⁺的含量有关，还与表生风化作用的强度相关，随表生风化作用的增强，颜色变浅，致密程度降低。（2）偏光显微镜下绿松石具隐晶～微晶结构，局部呈放射球粒状结构、鳞片状结构。绿松石中常含有深褐色的铁线，铁线物质由铁质、碳质、少量绢云母和细小的粘土矿物组成。（3）绿松石的显微结构形态多样，微晶多呈菱形鳞片状、柱状、片状和薄板状分布。（4）不同形态、不同产地、不同颜色的绿松石表现出的红外吸收光谱特征差异不明显，具有相同基团的振动特征峰，仅在个别波数范围内存在微小的偏差，3505～3070cm^-1范围内红外吸收谱带为ν（OH）伸缩振动所致，1198cm^-1～1010cm^-1的红外吸收峰归属为ν₃（PO₄）伸缩振动；δ（OH）弯曲振动致红外吸收谱带在839 cm^-1～781 cm^-1；ν₄（PO₄）弯曲振动致红外吸收谱带主要为652 cm^-1～483cm^-1。（5）绿松石在可见光波长范围内，显示两条吸收强度不等且宽窄不一的特征吸收谱带，即分别由Fe³⁺d-d电子跃迁引起的a₁带423～438nm和Cu²⁺d-d电子跃迁引起的a₂带683～688nm，a₂带的吸收强度普遍较a₁带宽大。（6）绿松石中水的总量和结合方式在一定程度上制约着绿松石的颜色。2．实验选择Al（H₂PO₄）₃溶液为主胶粘试剂，以MgO为添加辅料，在没有加压的条件下以“浸泡——加热——保温——冷却——加工”为基本实验过程对疏松绿松石进行改性处理。试验结果表明：Al（H₂PO₄）₃溶液的性质，浸泡时间，浸泡温度，浸泡方式，保温温度，保温时间和溶液中添加物MgO的含量对疏松绿松石的改性效果均有不同程度的影响。（1）通过分别研究在每个工艺参数不同条件下的改善效果，选择了效果最佳的工艺条件，即选用的Al（H₂PO₄）₃胶粘剂质量分数约为50％，PH值控制在1.5～2，每100ml胶粘剂溶液中添加5～7gMgO；疏松绿松石宜采取密封并辅以低温浸泡处理，根据绿松石相对致密程度及尺度大小的变化浸泡时间一般为几天至十几天不等；充填处理后的绿松石需在低温凝胶硬化后才能进行加热固化处理，对一次处理效果不佳或者大块的疏松绿松石可以按照上述过程进行两次或多次浸胶充填处理。只有严格控制上述工艺条件，改善的效果才能达到最佳。（2）利用磷酸铝胶粘剂溶液充填处理后的绿松石质地坚硬，显微硬度为106～297N／mm²；颜色可以加深至饱和度很高的蓝绿色、绿蓝色和绿色，外观仿真效果好、宝石学性能优良，加工工艺性能与天然绿松石一致，利用常规宝石学测试方法不易鉴别，可加工成首饰用绿松石珠链、戒面、吊坠等。3．选用充填处理绿松石试验中相同配比的胶粘剂溶液对小颗粒绿松石废弃料进行压制再造处理。（1）确定了绿松石废弃料的分选提纯方案，即利用重选和浮选联合选别工艺提选出绿松石中的碳质杂质并选用一定浓度的HCl、硫代硫酸钠和草酸与绿松石综合反应最大程度的提选出了绿松石废弃料中的杂质Fe³⁺。（2）在绿松石废弃料压制再造试验中，胶粘剂的添加比例、绿松石粉体粒度、加压压力、加压时间、保温温度和保温时间对绿松石废弃料的处理效果均有不同程度的影响，效果最佳的工艺条件为：胶粘剂添加比例为23％-25％，粉体粒度不小于250目，加压压力1.5*10⁴MPa／m²～3.0*10⁴MPa／m²，加压时间不得低于10min，压制好的坯体室温自硬化1～2天后按照一定恒温曲线进行加热固化。（3）压制处理后的绿松石颜色均匀、色调单一，多为浅蓝绿色，与处理前绿松石粉末颜色一致；显微硬度在105～198N／mm²，透明度、光泽、韧性和耐久性较好；其宝石学特征，如光泽，折射率，紫外荧光等与天然绿松石相近，加工工艺性能优良，可加工成首饰用绿松石珠链和戒面。4．对处理前后绿松石的显微结构研究和化学成分分析结果表明：（1）处理后绿松石的结构致密程度、硬度和颜色受控于磷酸铝胶粘剂的填充含量。完全被填充、胶粘剂含量较高的部位，结构致密，颜色较深；填充不完全、胶粘剂含量低的部位，结构疏松，硬度较低，颜色较浅。（2）绿松石经浸胶充填和压制再造处理后，胶体均呈凝胶状分布在绿松石原有的微孔隙间，绿松石微晶晶形较处理前表现模糊，边棱表现圆滑，绿松石与胶粘剂在粘合过程中，部分微晶发生有微弱的溶解重结晶反应。（3）EDX测试和化学成分分析综合表明，处理后绿松石内部胶粘剂填充充分的部位，P₂O₅含量明显增高，MgO含量有0.08％～0.31％的升高，其它主要化学组分变化不大；处理后绿松石主要致色元素与处理前一致，均为Cu和Fe。（4）处理后绿松石颜色色调与处理前绿松石中的Cu、Fe含量有关，Cu／Fe比值大的绿松石经处理后偏蓝色，Cu／Fe比值低的绿松石经处理后偏绿色。5．对处理前后绿松石的红外吸收光谱和XRD粉晶衍射研究结果表明：（1）处理后绿松石分子结构和矿物组构与处理前天然绿松石一致，但产生了一定程度的非晶质化。分析认为处理后绿松石中非晶质化的产生与磷酸铝胶粘剂的填充作用有关，即磷酸铝胶粘剂在固化过程中脱水形成无机高分子网络结构。（2）在压制处理绿松石试验中，磷酸铝胶粘剂的添加，促进了绿松石微晶（120）面网的发育，但在充填处理绿松石中表现得并不明显。6．对处理前后绿松石的差热曲线研究结果表明：处理后的绿松石吸热和放热反应温度较处理前天然绿松石相比均有一定程度的降低，主要是由于添加入的磷酸铝胶粘剂具有较低的吸热反应温度所致。7．探讨和研究了无机胶粘剂对绿松石的改善机理和反应机制。在对疏松绿松石浸胶充填或对绿松石废弃原料压制再造的条件下，磷酸铝胶粘剂溶液通过布朗运动沿着绿松石微孔隙或微粒边界逐渐浸润至绿松石内部，经过加热发生聚合固化，并导致部分绿松石微晶溶解重结晶，最终这些反应产物充填了绿松石内部原有的孔隙，并以原子和分子范围内的微观作用、宏观结合和接触界面的化学键力胶结了原来仅为松散镶嵌的绿松石矿物颗粒，一方面降低了绿松石微粒间的孔隙度，减少了光的漫反射，使处理后的绿松石颜色加深，透明度提高，另一方面使处理后绿松石的矿物颗粒连接得更加紧密，达到提高硬度，改善工艺性能的目的。更多还原

【Abstract】 Turquoise is a hydrous Copper-aluminum phosphate, with the chemical formula CuAl₆ [PO₄]₄（OH）₈·4H₂O, which is triclinic, and most named after their pineal shape and the blue-greencolors. It’s a very popular traditional ancient and modern precious jade.In recent years, the new turquoise deposit and exploitation is far below the social demand,resulting in the imbalance between supply and demand of the high-quality turquoise orebecoming more and more serious in the jewelry market both at home and abroad, which has ledto a sharp rise of the turquoise’s price for five years. Constrained by the complex depositgeological conditions, the original quality of most turquoise is quite poor, bad color, light-coloredor colorless, cracks and porosity are ubiquitous, so it is too difficult to achieve high quality andlose their due value. Because of the behindhand mining technology and processing equipment ofturquoise mine, and the low resource utilization rate of resources, together with the disorderlycompetition of turquoise processing industry, most turquoise substantial resources were wastedand several tons of small slag and residual slag powder of turquoise were left abandoned. Sosynthetic recycling for the turquoise resources should be strengthened. Meanwhile, the traditionalplastic injection treated turquoise are filled with many organic polymers, resulting in thecomposition, structure and physical characteristics of turquoise are quite different from naturalturquoise. Moreover, this method is limited to larger turquoise material, but difficult to specifythe implementation of the small particles turquoise material. Therefore, it is very important toresearch the recycling of wasted turquoise, improving the quality grade of turquoise, andalleviating the short supply of turquoise.The small particles of waste turquoise materials and sub-monomer turquoise materials havebeen chose for the study. Selecting Al （H₂PO₄）₃ with chemical composition is similar to turquoiseand related supplementary materials, using different chemical formulas and under differentconditions, the small particles of waste turquoise materials and sub-monomer turquoise materialsare improved to a larger monomer scale and a higher quality jewelry grade respectively by theway of pressing reconstruction and soaking filling. It will provide a scientific basis for recycling of turquoise resources in our country. The main conclusions are as follows:1. The research is focus on the turquoise deposit in Qingu, Labashan in Zhushan county andYun county of Hubei province as well as Maanshan, Anhui Province. The geologicalcharacteristics, chemical composition, microstructure and colorific mechanism of naturalturquoise have been studied. The result shows that: （1） the color of turquoise is controlled by Fe³⁺,Cu²⁺, and surface weathering intensity. （2） The structure of turquoise can be described asmicrocrystal-squama texture and spherulitic texture. There are often impurities contained by iron,carbon, a small amount of sericite and small clay mineral in turquoise. （3） The microstructure ofturquoise microcrystal can be described as scale-like, columnar, and sheet-like shape. （4） Thespectra of the turquoise from different localities are basically similar and subtly different. The3505～3070 cm^-1 spectra assigned to theν（OH） stretching vibrations and the bands observed at1198-1010 cm^-1 assigned toν₃ （PO₄） antisymmetric stretching vibrations. The spectra peaks at839 cm^-1～781cm^-1 and 652 cm^-1～483cm^-1 are attributed to theδ（OH） bending vibrations andν₄（PO₄） bending vibrations, respectively. （5） In the visible wavelength range, two characteristicabsorption bands of turquoise a₁ and a₂ can be observed, which are caused by Fe³⁺ d-d electrontransitions with 423～438nm and Cu²⁺d-d electron transitions with 683～688nm, respectively. （6）The combination and content of H₂O constraint the color of turquoise at a certain extent.2. The basic method of processing loose turquoise is: Al（H₂PO₄）₃ solution as main adhesivereagents, MgO as accessorial material, and "soaking-heating-insulation-cooling-processing"as the basic experimental process at constant pressure. The result shows that, thequality of Al（H₂PO₄）₃, soaking time, soaking temperature, soaking way, holding temperature,holding time, heating rate and the solution of additives have different effects on processingeffects. （1） By studying the effect at individual process parameters under different conditions, abest process conditions is selected, that is, the selection of Al（H₂PO₄）₃ mass fraction of about50%, PH value of control at 1.5～2, and 5～7g MgO per 100ml adhesive. The soaking of loosenturquoise under low temperature is appropriated. According to the changes of quality and scale ofturquoise, the soaking time is generally ranging from a few days to ten days. Filled turquoises arerequired heat-curing treatment after the gel at low temperature. The turquoise with insufficienttreatment can be carried out in accordance with the above process of filling, taking two or moretimes soaking treatment. Only the processing conditions are strictly controlled, the results wouldbe optimal. （2） After the treatment, the color of loose turquoise can be enhanced to a high degreeof saturation of blue-green, green-blue and green, transparency improved; gloss strengthened,and has good durability. The hardness can increased to resist scored by forceps, withmicro-hardness between 106～297N/mm².The structure is denser and has good processingperformance. Cutting and grinding processing is consistent with natural turquoise. The looseturquoise after treatment can be processed into jewelry with turquoise beads, ring stones, andpendants et al.3. The small particles of wasted turquoise are pressed reconstruction with the same adhesivesolution of the filling treatment experiment. （1） Sorting purification of the turquoise scrapsmaterials and gravity concentration and flotation united sorting method are selected to screen out the carbonaceous impurities from turquoise, and selecting HCl, hyposulfite and oxalate to mixthe turquoise for general reaction to clean out the Fe³⁺ impurities from turquoise. （2） In theprocess of wasted turquoise reconstruction experiment, proportion of adhesive, size of turquoisepowder, and time of compression stress, insulation temperature and holding time show differenteffects on results. The optimal process conditions are: adhesive ratio between 23%-25%, powderparticle size is no less than 250 eyelet, compression stress is between 1.5*10⁴MPa/m² and3.0*10⁴MPa/m², pressure time not less than 10 min, heat solidify suppressed body afterself-hardening at room temperature for 1～2 days in accordance with a certain temperature curve.（3） After the treatment, the color of turquoise is uniform with single color-light blue green, andmicro-hardness is between 105N/mm² and 198N/mm². The gemology characteristics ofturquoises after treatment, such as gloss, refractive index, UV fluorescence and so on, are similarwith the natural ones. With excellent processing properties, the turquoises after treatment can beprocessed into jewelry with turquoise beads and ring stones.4. The study of microstructure and chemical composition analysis of the turquoises before andafter treatment indicate that: （1） the dense degree, color and hardness of turquoise after treatmentare controlled by aluminum phosphate adhesive fller’s content. The turquoise filled morecompletely and with higher levels of adhesives, the structure is denser and the color is darker. （2）The micro-pores of the turquoise after treatment are completely filled as gelatinous. Moreover,the turquoise crystallites are dissolved relatively smooth and some have been dissolved withweak recrystallization reaction. （3） The EDX test and chemical composition analysis show thatthe turquoise with filled adhesive has higher content of P₂O₅. MgO content has increased to0.08%～0.31%, but other chemical compositions have no notable changes, so on with thecoloring elements Cu and Fe. （4） The color of treated turquoise is related to the former Cu and Fecontent, a high ratio of Cu/Fe conduce blue, but high Fe content conduce green.5. The study of IR spectra and XRD of the turquoises before and after treatment show that: （1）the mineral composition and molecular structure of turquoise have no noticeable change, buthave a certain degree of amorphous. The amorphous structure is relevant with the filling ofaluminum phosphate that is the inorganic polymer network structure formed when the aluminumphosphate adhesive dehydrated. （2） In the pressing reconstruction experiment, the addition ofaluminum phosphate adhesive promoted microcrystal turquoise net plane （120） growth, but wasnot apparent in filled turquoise.6. The DTA study shows that the endothermic and exothermic reaction temperatures of theturquoise after treatment have a certain degree of fall than the natural ones caused by the additionof aluminum phosphate.7. The improving principle and reaction mechanism for recycling of turquoise are summarized.According to the micro-Brownian motion, aluminum phosphate solution gradually infiltrated tothe interior of turquoise along the micro-pores or the borders of turquoise particles. Thealuminum phosphate within turquoise polymerized when heating and made some turquoisecrystallites dissolved and recrystallizated. Then the reaction products filled the originalmicro-pores, and cemented the original loose mineral particulates by the combination of micro-macro integration and chemical bond. On the one hand, the porosity is lower, the diffusereflectance of light is reduced and the transparency and color of turquoise are improved. On theother hand, the mineral particulates connect more closely to make the hardness and the processperformance improved.更多还原