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181.
The influence of type and amount of clays present in soils on their properties is well understood. The clays exert their influence through large specific surface area and charges on them. Their effect is mostly exhibited through inter particle bonding and subsequent particle associations. The mineralogical influence of soils in water is well documented. However, the change in soil water system because of presence some of the contaminants can greatly influence the soil behaviour. Some of the changes are due to formation of new compounds due to interactions between the soil and pollutant. The paper reports the effect of interaction of kaolinite mineral with alkali on the index properties of soils from which the geotechnical behaviour can be understood. Detailed X-ray diffraction studies have shown that sodium aluminum silicate hydroxide hydrate (NASH) is formed by clay alkali reactions. The type and amount of formation of the compound is influenced by the concentration of alkali solution. While the compound formed is in smaller quantities with 1 N NaOH solution, significantly high quantity is formed with 4 N NaOH solution. Presence of alumina is shown to play a significant role. It was observed that the formation of sodium aluminum silicate hydroxide hydrate is reduced in the presence of alumina. Specific gravity of contaminated clay soil was reduced which confirms the formation of new compounds. Water adsorption and specific surface area of soil are also influenced due to soil alkali interaction. The changes in the free swell and index properties of soil in the presence of alkali have been explained by the changes in soil fabric and the formation of new compound.  相似文献   
182.
Moderate to poorly sorted immature Parsora sandstones rich in K-feldspar show much of the feldspar during early diagenesis transformed to kaolinite after prolonged interaction with acidic pore solutions. The kaolinitic epimatrix formed and was later partially or wholly converted as an orthomatrix producing chert-phyllosilicate assemblage. Ferric oxide, bleached biotite, kaolinite and quartz cement denote an oxy-acidic early diagenetic environment. Late diagenesis involved neoformation of primary or secondary matrix, illitisation of montmorillonite and muscovite authigenesis. The high pressure-temperature regime required for these transitions resulted from tectonic activity during Triassic-Jurassic times. Carbonate-chlorite appeared late in the sediments denoting an alkaline-reducing condition at the late part of the diagenesis. Finally, the secondary porosity developed through carbonate dissolution was later filled up with allochemical ferric iron cement receiving ions from the percolating meteoric water.  相似文献   
183.
本文将微波技术引入到制备高岭石/有机物插层复合物的研究中,以DMSO为前驱体,研究了微波辐射对高岭石的有机插层、取代、原位聚合作用.发现微波能加快插层和置换反应,极大地缩短反应时间.微波辐射下插层时间为30 min时,插层率即可达到75%以上,置换反应50 min,置换率达到77%以上.同时发现微波在反应中对高岭石具有剥片效果.采用X射线衍射、FT-IR光谱、TG、TEM等技术对插层复合物及微波作用机理进行了探讨.  相似文献   
184.
A detailed experimental investigation has been carried out to study the use of ferric chloride salt to control the undesirable volume changes induced by high concentrated alkali contamination on kaolinitic red earth. X-Ray diffraction studies have revealed that soil alkali interactions produce mineralogical changes and formation of new mineral such as zeolite, which are responsible for observed swelling in non-swelling kaolinitic soil. Loss of ferric oxide, which are known cementing agents has been attributed as one of the reasons for swelling in alkali contaminated soils. The consolidation behaviour of soil compacted with 5% ferric chloride solution by weight of solutions and inundated with alkali solutions as well as soil compacted with alkali and inundated with 5% ferric chloride by weight of solutions has been studied. To study the effect of amount of ferric chloride, the volume change behaviour of soil compacted with different weight percentages of ferric salts by weight of soil (1%, 3%, and 5%) and inundated with alkali solutions has also been studied. The swelling of soil compacted with alkali has been checked by inundating with 5% ferric chloride solutions due to neutralization of alkali and is not controlled when soil compacted with 5% ferric chloride solutions is inundated continuously with alkali solutions. Further, even when the soil is treated with higher amounts of ferric chloride, in the range of 1–5% by weight of soil, the swelling is not controlled. X-ray diffraction studies have shown that the formation of zeolite is not inhibited in the presence of ferric salts.This study clearly shows that ferric chloride treatment can overcome the effects of small concentrations of alkali; it is ineffective to overcome the large and continued exposure of soils with alkali contamination.  相似文献   
185.
江西龙南花岗岩稀土风化壳中粘土矿物的研究   总被引:8,自引:0,他引:8       下载免费PDF全文
本区燕山早期花岗岩发育的风化壳中的粘土矿物以高岭石和埃洛石(7Å)为主;蒙脱石、三水铝石及其它为新查明矿物。据粘土矿物组合特征,自风化剖面深部到地表分为三个带:含蒙脱石带,高岭石和埃洛石(7Å)带,含三水铝石带。本文探讨了矿物在风化过程中的生成演化顺序,并进行了热力学的解释。据各带粘土物质的阳离子交换量与稀土含量变化的不一致关系认为,稀土在C带中的富集是化学风化的结果,与粘土矿物组合无关。  相似文献   
186.
渤海C油田东营组沉积特征及成岩作用复杂,物性变化大,油气显示活跃,存在大量录井显示好的高阻水层,流体性质判别难度大。结合录井及岩心、岩矿等资料进行了综合分析,研究认为:以高岭石为主的粘土矿物含量高及残余油饱和度高是形成高阻水层的两个主要因素。在成因分析的基础上,提出了流体替换法和深电阻率与密度曲线交会法快速识别高阻水层。实际资料应用表明,归一化后深电阻率与密度差值ΔRd-Δρ是C油田东营组油藏油、水层识别中的敏感参数,建立ΔRd-Δρ与深电阻率Rd的交会图版,油层主要分布在ΔRd-Δρ大于2.3的区域。研究方法对于C油田乃至渤海中深层测井综合评价具有很好的指导作用。  相似文献   
187.
以皂石、高岭石、绿泥石和伊利石为原材料,分别与赖氨酸进行反应,研究赖氨酸在上述粘土矿物上的吸附行为, 并运用粉末X-射线衍射技术(XRD)、傅里叶变换红外吸收光谱术(FTIR)和热重(TG)等分析方法,表征反应前后粘土 矿物的变化。实验结果表明,不同粘土矿物对赖氨酸的吸附等温线均符合Freundlich等温方程,且不同粘土矿物对赖氨酸的 饱和吸附量大小顺序为:皂石>蒙脱石>绿泥石>高岭石>伊利石;XRD结果表明皂石对赖氨酸的吸附发生在矿物层间,而绿 泥石、高岭石和伊利石对赖氨酸的吸附主要在矿物表面进行;FTIR和TG结果表明赖氨酸主要取代粘土矿物层间吸附水,以 氢键的形式与Si-O-Si(IVAl)键合。实验结果将有助于进一步探明环境中粘土矿物对有机质的吸附机理。  相似文献   
188.
董晋琨  杜杨松 《地球学报》2017,38(2):208-222
寿山石是一种以黏土矿物为主要成分的用于工艺美术雕刻、印章篆刻的玉石,因主要产于福建省寿山而得名。本文在野外地质调查的基础上,通过肉眼、偏光显微镜和扫描电子显微镜(SEM)的观察以及电子探针、X射线粉晶衍射、红外光谱和差热等分析手段,对福建寿山石各矿床的主要矿石的类型及其特征、矿石的主要组成矿物、显微结构及其晶体结构特征等方面进行深入研究。根据对高山、旗降、峨嵋、月尾四个寿山石矿床矿石的成分分析,将寿山石原生矿石分为迪开石型、高岭石型、叶蜡石型和伊利石型四种主要类型。寿山石的结构主要有显微隐晶、显微隐晶-微晶、显微微晶结构。高山矿石由纯净的有序迪开石组成,峨嵋矿石由纯净的2M型叶蜡石组成,部分月尾矿石由纯净的2M1型伊利石组成,旗降矿石以有序高岭石为主,含有少量迪开石或高岭石-迪开石的过渡矿物,部分旗降矿石以2M型叶蜡石为主,含有少量高岭石。根据矿床地质产状、矿石结构、矿物共生组合等特征分析,寿山石的成矿环境为还原环境,属于热液蚀变成因。  相似文献   
189.
为探讨天然黏土矿物及有机质对纳米乳化油在多孔介质中迁移滞留的影响,本文选取高岭石和蒙脱石这两种黏土矿物以及有机质的典型代表腐殖酸,开展了单一矿物、有机质及有机矿质复合物对纳米乳化油的吸持批实验研究,并运用比表面积全分析、扫描电镜(SEM)、傅里叶红外光谱(FTIR)、X射线衍射(XRD)等技术手段探讨了吸持机理。实验结果表明,介质对纳米乳化油的吸持均符合Freundlich模型;单一矿物及腐殖酸对纳米乳化油的吸持能力表现为:蒙脱石>腐殖酸>高岭石,有机矿质复合样品的吸持能力表现为:蒙脱石-腐殖酸>高岭石-腐殖酸,且均大于其对应的单一样品,出现了“1+1>2”的现象,表明介质组成越复杂,对纳米乳化油的吸持滞留程度越大。进一步分析证实,纳米乳化油主要通过氢键和疏水作用吸持在矿物和腐殖酸表面,表面结构性质是高岭石和蒙脱石吸持过程中的主导因素,因此蒙脱石具有更强的吸持能力,而腐殖酸的吸持主要通过颗粒间聚集作用来实现;对于复合样品,吸持主要通过氢键、配体交换和疏水作用结合来实现。腐殖酸与矿物的复合会增加吸持位点并且增强矿物表面疏水性,从而促进吸持。腐殖酸与纳米乳化油的共吸...  相似文献   
190.
浙江方家山高岭土矿床中高岭石亚族矿物的研究   总被引:4,自引:0,他引:4  
珍珠陶石、地开石和高岭石是高岭石亚族矿物的三种多型。其中高岭石最常见,地开石较少见,而珍珠陶石是十分罕见的多型。本文作者应用X射线衍射、红外光谱和醋酸钾夹层化合物的方法,研究了浙江方家山高岭石矿物特征。研究表明,用醋酸钾为夹带剂形成的珍珠陶石夹层化合物具有14.0的特征衍射峰,经水分子取代后形成8.35特征的珍珠陶石水合化合物,而高岭石仅部分形成7.30水合夹层化合物。从而确定了方家山高岭土矿床是以高岭石为主含珍珠陶石的矿床,其珍珠陶石主要赋存于粗粒级的高岭土中。高岭石与珍珠陶石晶畴呈消长关系可能说明珍珠陶石是后期较强应力下由高岭石转变来的。  相似文献   
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