Removal of Cu2＋ from Aqueous Solutions Using Na-A Zeolite from Oil Shale Ash

Na-A zeolite was synthesized using oil shale ash （OSA）, which is a solid by-product of oil shale proc- essing. The samples were characterized by various techniques, such as scanning electron microscopy, X-ray diffrac- tion and Brunaner Emmet Teller method. The batch isothermal equilibrium adsorption experiments were performed to evaluate the ability of Na-A zeolite for removal of Cu （II） from aqueous solutions. The effects of operating pa- rameters, such as concentration of copper solutions, adsorbent dosages, pH value of solutions and temperature, on the adsorption efficiency were investigated. The equilibrium adsorption data were fitted with Langmuir and Freundlich models. The maximum adsorption capacity of Na-A zeolite obtained from the Langmuir adsorption iso- therm is 156.7 mg.g-t of Cu （lI）. The increase of pH level in the adsorption process suggests that the uptake of heavy metals on the zeolite follows an ion exchange mechanism. The batch kinetic data fit the pseudo-second order equation well. The thermodynamic parameters, such as changes in Gibbs free energy （AG）, enthalpy （AH） and en- tropy （AS）, are used to predict the nature of the adsorption process. The negative AG values at different tempera- tures confirm that the adsorption processes are spontaneous.

Preparation of Single Phase Na-X Zeolite from Oil Shale Ash by Melting Hydrothermal Method

A single phrase Na - X zeolite was synthesized from pretreated oil shale ash by alkaline fusion and hydrotherreal treatment. Eff3cts of the NaOH concentration, crystallization time ant temperature on the formation of Na-X zeolite were studied in detail. The single phase Na- X zeolite powders can. be prepared by alkaline fusion o.f pretreated oil shale ash at 600 ℃ .for 1 h, and crystalli-zation at 80 - 100 ℃ .for 8 - 10 h with NaOH concentration of 3 -3. 5 tool · L-1. Na - A zeolite appears when decreasing NaOH concentration, crystallization time or temperature, ant an unnamed zeolite emerges when prolonging crystallization time or raising crystalli-zation, temperature. SEM micrographs suggest that the aggregates of Na-X zeolite particles have perfect dispersity and uniform granular with about 1.5 μm in size, and most of the Na-X zeolite crystals display a regular octahedral structure with the size of about 500 nm. The specific surface area of the powders with single Na-X zeolite phase reaches the maximum value of 488. 163 2 m2· g -1, larger than that of multiple zeolite powders.

Leachability of Oil Shale Ash from Isfir Al-Mahata Oil Shale, Southern Jordan

This paper presents the first study on the oil shale (OS) ashing and OS ash leachability of Jordanian OS located further in the south. The studied OS is from Isfir Al-Mahata subsurface OS located 10 km south of Ma’an. Chemical and physical characterization of the OS ash was performed and compared with original OS. Ashing OS was conducted at different temperatures. Important parameters affecting OS ash leachability were also investigated. The leachability of certain heavy metals was investigated based on clear leaching protocol. The Fisher Assay analysis result indicates that this OS type has quite higher moisture content, lower oil content, and higher spent shale compared with other Jordanian oil shales. Ashing of OS at higher temperatures (950°C) resulted in the disappearance of silica, due to its complete reaction with lime and Al, and formation of Anhydrite and cement materials like, Portland cement. The leachability analysis indicates that for most elements the leachability is high at low pH. The released heavy metals concentrations are below EPA limits. Chromium and lead are leached out more than other elements with the exception at low pH. In general, the higher the ashing temperature is, the lower the release of elements is. The chemical composition of the ash and the leachability results suggests that it has high fixing capacity toward the heavy metals present in the ash.

Adsorption of Heavy Metal Ions from Aqueous Solutions by Zeolite Based on Oil Shale Ash： Kinetic and Equilibrium Studies

Na-A zeolite was successfully synthesized via the alkaline fusion method with oil shale ash as the raw material. The adsorption capacity of it was tested by removing Cu2＋, Ni2＋, Pb2＋ and Cd2＋ from aqueous solutions. The results reveal the maximum adsorption capacity of adsorbent for Pb2＋, Cu2＋, Cd2＋ and Ni2＋ were 224.72, 156.74, 118.34 and 53.02 mg/g, respectively. The effects of contact time and pH value of solutions on the adsorption effi- ciency of the zeolite were evaluated. Besides, The equilibrium adsorption data and the batch kinetic data were correlated with Langmuir and Freundlich models and the pseudo-first-order and pseudo-second-order models separately. The results show that the Langmuir isotherm and the pseudo-second-order equation were more suitable for the adsorption of Na-A zeolite for the metal ions. In addition, Thermodynamic parameters of the adsorption（the Gibbs free energy, entropy, and enthalpy） were also evaluated and discussed. The results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions and the synthesized zeolite was an effective adsorbent for the removal of metal ions from aqueous solution.

Synthesis of Na-X zeolite from Longkou oil shale ash by alkaline fusion hydrothermal method

Na-X zeolites were synthesized by Longkou oil shale ash with the alkaline fusion hydrothermal method.The effects of fusion temperature,ash to NaOH ratio,solid-liquid ratio,crystallization time and crystallization temperature on the crystallinity of zeolites were investigated.The synthetic products were characterized by Xray diffraction(XRD),scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),29Si nuclear magnetic resonance spectroscopy(29Si NMR)and N2 adsorption-desorption.The results showed that the conditions to synthesize Na-X zeolite were:Longkou oil shale ash to sodium hydroxide ratio 1:1.2 g・g^(-1),fusion temperature 600℃,solid-liquid ratio 1:4 g・mL^(-1),crystallization time 24 h and crystallization temperature 80℃.The zeolite with high crystallinity(91.32%)was synthesized:the product exhibiting octahedral particles observed by SEM,and the calculated Si/Al ratio in Na-X zeolite being 1.23 from^(29)Si MAS NMR spectra,which was consistent with the observation from XRD.

Removal of Chromium（VI） from Groundwater Using Oil Shale Ash Supported Nanoscaled Zero-valent Iron

Oil shale ash（OSA） supported nanoscaled zero-valent iron（OSA-nZVI） was used as a rapid and efficient reductant for Cr（VI） reduction. The optimal mass ratio of nZVI to OSA and the optimal dosage were explored. The effects of initial pH, reaction temperature, initial Cr（VI） concentration, and common cations and anions in ground- water on Cr（VI） reduction were determined in batch experiments. The results show that the optimum initial pH is 5.0. The reaction temperature has a positive effect on Cr（VI） reduction while the real groundwater has a negative effect. Additionally, 84.22% Cr（VI） was still reduced by 3 g/L OSA-nZVI（1：2）（mass ratio of OSA to Fe^0 was 1：2） within 120 min for 50 mg/L Cr（VI） under conditions of 10℃ and unadjusted pH.

油页岩灰基分子筛的制备及对亚甲基蓝的吸附

针对油页岩灰基分子筛的类型和结构与其吸附染料分子能力间构效关系不明确的问题,以北票油页岩灰(BPA)为原料制备了NaP1、NaX和NaA三种不同类型的分子筛,并将其用于吸附亚甲基蓝(MB),考察了分子筛用量、MB初始浓度、pH、吸附温度和时间对吸附的影响规律,阐明了分子筛吸附MB过程的吸附机理,明确了不同类型分子筛与其吸附MB能力之间的构效关系。结果表明,分子筛的比表面积和孔结构对其吸附能力影响较大,在最优化吸附条件下,NaP1、NaX和NaA型分子筛对MB的去除率分别为99.7%、94.5%和96.5%,且均具有良好的可再生重复利用性能。吸附过程符合拟二级动力学和Langmuir等温吸附模型。NaP1型分子筛对MB的吸附是自发的、吸热的熵增过程;NaX和NaA型分子筛对MB的吸附是自发的、放热的熵减过程。吸附机理研究表明,静电引力、氢键和孔扩散是分子筛吸附MB过程的主要推动力。可为油页岩灰的资源化利用以及低成本吸附法处理印染废水提供有价值的实践和理论借鉴。

燃烧过程对页岩灰孔隙结构的影响

页岩灰为油页岩及其半焦的燃烧产物,可作为建筑原材料、化工填料和吸附剂等,具有一定的工程应用价值。采用氮气等温吸附/脱附法对油页岩燃烧生成的页岩灰的孔隙结构进行了测量,并对不同升温速率和不同终温所得到的页岩灰的孔隙结构进行了比较,结果表明:如果油页岩在快速升温条件下燃烧所放出的热量能够被周围环境吸收而使得油页岩颗粒温度始终低于其灰熔点温度,所得到的页岩灰的孔容积和孔比表面积较大,适宜工业应用。

利用油页岩灰渣制备通用硅酸盐水泥

采用正交试验确定水泥熟料最佳组成配比:石灰饱和系数为0.92、硅率为2.5、铝率为1.5;水泥熟料最佳煅烧温度为1 350℃。按上述条件,利用工业原料配制水泥熟料,根据其XRD结果可知,矿物组成与吉林亚泰水泥厂的熟料相似。将油页岩灰渣作为混合材,直接掺加到水泥厂熟料中。实验结果表明:随着油页岩灰渣掺量的增加,3d强度下降明显;但后期补强作用较高,28d强度较为稳定;在水泥强度满足PC32.5标准的前提下灰渣的最大掺加量以35%～40%为宜。

油页岩灰渣制备人造大理石及其性能

利用油页岩灰渣、不饱和聚酯树脂为主要原料,辅助加入固化剂和促进剂,室温固化合成一种新型人造大理石装饰材料。运用实验系统研究原料配比、固化剂和促进剂用量、固化时间、树脂类型与填料粒度等因素对材料性能的影响,并确定了大理石制备的最佳配方。基层最佳配方（质量分数）：不饱和树脂1号为20%～27%、引发剂0.5%～2.25%、促进剂0.5%～1.5%、油页岩灰渣50%～70%、碳酸钙粉5%～20%;表层最佳配方（质量分数）：不饱和树脂1号为25%～30%、引发剂0.5%～2.0%、促进剂0.5%～2.0%、氢氧化铝40%～50%、碳酸钙粉20%～30%。采用该方法制备的人造大理石外形平整美观,压缩强度为79 MPa,弯曲强度为7.4 MPa,放射性比活度IRa和Ir分别为0.67、0.45,质量符合国家标准。

油页岩灰渣提取白炭黑的方法

以油页岩灰渣制备的水玻璃为原料,结合传统沉淀法和热风干燥工艺成功地制备了白炭黑。实验过程中研究了各种因素对白炭黑性质的影响,并确定了白炭黑的最佳制备工艺：水玻璃中w（SiO2）为8.1%、c（H2SO4）为1.5 mol/L,陈化时间为8 h,反应温度为70~80℃,pH值为8.0。透射电镜分析结果表明：采用热风干燥技术制备的白炭黑平均粒径约为50 nm,而且团聚体较少,性能优于烘箱干燥制备的白炭黑。

油页岩飞灰对重金属离子的吸附动力学及热力学

采用批式振荡吸附法研究了燃油页岩电厂循环流化床锅炉飞灰对重金属离子Pb2+、Cu2+、Zn2+、Cd2+的吸附动力学及吸附热力学特性,并提出了吸附机理。结果表明,油页岩飞灰对Pb2+、Cu2+、Zn2+、Cd2+的吸附平衡数据符合Langmuir和Freundlich吸附等温方程,但Freundlich方程能够更好地描述吸附等温线。在油页岩飞灰对重金属离子吸附的初始阶段,拉格朗日准一级动力学方程、准二级动力学方程、Elovich方程、粒子内扩散模型均能很好地反映吸附模式,而整个吸附过程则遵循二级反应动力学方程,其吸附过程是液膜扩散和粒子内扩散共同作用的结果。油页岩飞灰对Pb2+、Cu2+、Zn2+、Cd2+的吸附是吸热反应。

油页岩灰作水泥混合材的研究

通过试验研究确定大庆油页岩灰符合火山灰质混合材要求,能与熟料掺混生产水泥。配制了不同油页岩灰掺混量的水泥样品,按照国标进行强度试验,并采用X-射线衍射仪分析了28d胶砂试块的物相组成。结果表明:随着油页岩灰掺量的增加,水泥样品胶砂强度整体呈下降趋势,且前期下降幅度大,后期小;高掺混量时熟料中的C3A矿物含量不足,试样检测出钙矾石;油页岩灰掺量为5～10%,水泥样品强度仍能达到与熟料的相同的强度等级;掺量为15～20%,其强度亦接近熟料的强度等级;掺量在20%以上时,强度下降显著。

二氧化钛改性油页岩渣对水溶液中亚甲基蓝和六价铬的吸附

以油页岩渣及其二氧化钛改性材料为吸附剂,探究它们去除水溶液中亚甲基蓝和六价铬的能力.通过实验,控制溶液的pH值、温度、初始浓度和接触时间,观察吸附效果变化特征,研究其动力学和热力学性能.实验表明,改性油页岩渣吸附亚甲基蓝和六价铬的吸附率是未改性的2—3倍,且改性油页岩渣对亚甲基蓝的吸附率可达97%,对六价铬的吸附率不到25%.吸附亚甲基蓝时,pH值越大,吸附效果越好;而吸附六价铬时,最适pH值为4.改性油页岩渣吸附亚甲基蓝实验符合准二阶动力学方程,计算得反应活化能为13.29 kJ.mol-1,表明此过程主要是物理吸附.在热力学方面,由范特霍夫方程计算得ΔG<0、ΔH>0,表明此过程自发吸热,可见此过程还伴有化学吸附.Langmuir和Freundlich等温模型拟合结果表明,Langmuir模型数据拟合甚佳,R2=0.9999,说明改性油页岩渣吸附亚甲基蓝是单分子层吸附.二氧化钛改性油页岩渣经7次回收利用后,对亚甲基蓝的吸附效果仅减少约1.5%.

油页岩灰酸碱离解法制备白炭黑的工艺比较

分别采用了酸碱离解2种方法从油页岩灰制备白炭黑,其中酸离解法的实验条件为8.50mol/L H2SO4,90℃下,离解4.0h,SiO2的浸出率为39.6%;碱离解法的实验条件为3.3mol/L NaOH,100℃下,离解4.0h,SiO2的浸出率为75.8%。碱离解法制备的白炭黑经X射线荧光分析,白炭黑的产品中的SiO2纯度为91.8%;经FT-IR检测白炭黑的化学结构为水合二氧化硅,并经XRD和TEM观察白炭黑的形貌为无定型状态,粒径在50nm以下,白炭黑的比表面积（BET法）为114m^2/g,pH值为5.5～6.0,加热减量为5.82%,1000℃灼烧量为6.16%,产品符合中华人民共和国行业标准HG/T3061-1999的要求。

油页岩灰渣制备聚氯化铝的工艺研究

以广东省茂名市油页岩灰渣为原料,用碱法制备聚氯化铝(PAC),考察了酸溶条件对产品的铝浸出率与盐基度的影响。结果表明,以油页岩灰渣制备聚氯化铝的最佳酸溶条件为:酸的质量分数为12%,酸量比n(HCl)∶n(Al2O3)=10,酸溶温度为110℃,酸溶时间为3 h。此条件下,铝浸出率为62.92%,聚合氯化铝的盐基度为82.25%。

核化和晶化时间对页岩飞灰微晶玻璃性能的影响

以页岩飞灰为主要原料,通过不同热处理过程制备了微晶玻璃。利用XRD和SEM测试手段,分析了核化时间和晶化时间对微晶玻璃晶相特征的影响。结果表明,晶化时间的增加使微晶玻璃主晶相钙长石含量降低,次晶相钙硅石含量逐渐增加;核化时间的增加有利于球状晶粒尺寸增大,晶化时间的延长使晶粒聚集成团,排列紧密。微晶玻璃具有较高的抗压强度和良好的耐腐蚀性,可作为天然石料的替代品和装饰材料。

油页岩灰渣酸法制备纳米白炭黑碱浸工艺研究

以茂名油页岩灰渣为原料,采用酸法制备白炭黑,考察了碱浸条件对二氧化硅产率的影响。实验得到制取白炭黑的最佳碱浸工艺:碱浓度为3 mol/L、碱用量(氢氧化钠与二氧化硅的物质的量比)为4∶1、碱浸时间为4.0 h、碱浸温度为90℃。在最佳条件下,白炭黑的产率为63.79%,粒径为54 nm。制得的白炭黑符合HG/T 3061—1999《橡胶配合剂沉淀水合二氧化硅技术条件》的要求。

油页岩灰渣综合利用技术研究进展

介绍了我国油页岩资源的开发与利用概况。针对油页岩开发中产生的大量灰渣,认为采用填埋和堆积的处理方式,不仅造成资源的浪费,且占用大量的土地资源、破坏周边生态环境。参考国内外对油页岩灰渣的处理工艺,总结了油页岩灰渣制作水泥、轻质砖材、白炭黑、微晶泡沫玻璃,烧制陶粒以及提取氧化铝等综合利用的方法,并对油页岩灰渣综合利用提出了建议。

油页岩渣制备洗涤助剂4A分子筛的工艺条件和性能研究

以油页岩渣为原料,采用水热合成法制得4A分子筛。重点考察了n(Na2O)/n(SiO_2)比、n(H_2O)/n(Na2O)比、晶化时间、晶化温度对分子筛Ca2+交换量的影响。适宜的合成条件为:n(Na2O)/n(SiO_2)=2.5,n(H_2O)/n(Na2O)=50,晶化时间18 h,晶化温度90℃。并用XRD、SEM测试手段对合成的分子筛的晶体结构、表面形貌等进行了表征,结果表明,制备的样品为4A型分子筛结构,属于立方形晶型。