湛江高岭土作FCC催化剂载体可行性试验研究

对湛江高岭土的物化性质进行分析测试,并对以湛江高岭土为载体制备的半合成催化剂进行评价。结果表明,湛江高岭土晶体结构以片状为主,粒度分布较为集中,化学组成与苏州高岭土基本相当;采用湛江高岭土为载体的催化剂,其质量指标和裂化性能与对比样相当,可以满足FCC催化剂质量指标的要求。     

Kaolin modified with sodium salt of rubber seed oil as a reinforcing filler for blends of natural rubber,polybutadiene rubber and acrylonitrile–butadiene rubber

Blends of natural rubber (NR) and synthetic rubbers are widely used in the rubber industry to meet specific performance requirements. Further, the emerging field of organomodified clay/rubber nanocomposites could provide a host of novel materials having a unique combination of properties to meet various stringent service conditions. Previous studies have shown that at very low dosages, china clay (kaolin) modified with sodium salt of rubber seed oil (SRSO) improved the cure characteristics and physico‐mechanical properties of NR. Results of the present study show improved cure characteristics and physico‐mechanical properties for blends of NR with butadiene rubber and nitrile rubber containing 4 phr of SRSO‐modified kaolin as indicated by reduction in optimum cure time along with higher tensile strength, tensile modulus and elongation at break for their vulcanizates as compared to those containing unmodified kaolin. The SRSO‐modified kaolin/rubber nanocomposites showed improved flex resistance, reduced heat build‐up, tan delta and loss modulus and higher chemical crosslink density index, indicating a reinforcing effect of the SRSO‐modified kaolin, enabling the nanocomposites to have potential industrial applications. © 2015 Society of Chemical Industry     

Iron minerals and their influence on the optical properties of two Indian kaolins

Kaolin is mostly associated with minor quantities of ancillary minerals containing transition elements such as iron and titanium. These ions impart color to the white kaolin which adversely affects its application in paper and paint industries. Hence their removal is of prime importance in the optimum utilization of kaolin. The coloring effect as well as the mode of removal of these impurities depends on the “species” of the ion and/or the type of mineral. The present paper deals with the investigation on two Indian kaolins of different geological origin, one from Gujarat state at the western part of India and the other from Kerala State at the southern most part. Detailed physical, chemical and mineralogical characterization of the samples was carried out. The product clays after beneficiation by size classification, high gradient magnetic separation and chemical leaching were found to be of acceptable grade for paper industry with respect to optical properties and particle size. The impurity minerals were concentrated by different methods so that their identification was easier. Attempts were made to study the Fe species by correlating the XRD, chemical assay, DCB treatment and EPR spectral information of the clay samples before and after beneficiation. Iron stained anatase was found to be the major impurity in the Gujarat clay whereas iron was present as oxide/hydroxide in the Kerala sample. The beneficiated products from the Kerala clay were found to have better optical properties.     

衬布用聚氨酯热熔胶粉的研究

衬布业界非常期盼聚氨酯热熔胶粉的面世,以进一步提高衬布的品质.但自上世纪90年代以来的研究报道却表明,这一设想并不乐观.首先现有的聚氨酯热熔胶并不完全能满足衬布业的需要,其次对聚氨酯的粉碎有一定的困难.通过研究,采用化学粉碎法,用不同细化助剂进行粉碎实验,找到了一种可以使普通聚氨酯热熔胶粉碎成胶粉的有效途径.可制备出满足衬布行业性能要求的粉末.结果表明,相同粘接条件下,聚氨酯热熔胶粉的剥离强度比聚乙烯衬布用热熔胶粉大一倍以上.     

磷钨酸/高岭土在烷基化工艺中提纯均三甲苯

本文用盐酸对高岭土进行酸改性,制得具有一定硅铝比的改性高岭土,以磷钨酸为活性组分,以酸改性高岭土为载体,采用等体积浸渍法制得磷钨酸/高岭土固体酸催化剂,并将其应用于烷基化-分离法提纯均三甲苯工艺中,得到满足工业要求的纯度为98.5%的均三甲苯产品。并用XRD和BET对磷钨酸/高岭土固体酸催化剂进行表征,研究了催化剂的性质与催化反应性能的关系。     

刚玉砖和铬刚玉砖的应用

刚玉砖及铬刚玉砖是石化行业造气炉和反应炉的关键耐火衬里材料。本文介绍了国产刚玉砖及铬刚玉砖的力学性能及其在石化行业气化炉和反应炉上的应用情况。结果表明 ,刚玉砖及铬刚玉砖主要理化性能和使用效果达到或超过同类引进产品 ,完全可以替代进口材料 ,满足了石化行业的生产需要     

立式辊磨在煤系高岭土高细粉制备中的应用

根据煤系高岭土干法制粉的工艺系统现状及对制粉系统的要求,介绍了 LM型立式辊磨机的结构、工作原理、及针对工艺要求对磨机做的特殊优化, 并分享一个实际投产运行的一个案例。结果表明：我公司针对325目高岭土立磨改进的技术路线具有可行性,同时证明立磨在煤系高岭土干法制粉行业中可以满足大规模生产作业,适合推广。     

梅州高岭土成分分析

高岭土有着独特的物理性质和良好的可塑性,成为造纸、陶瓷、橡胶、耐火材料等几十个行业所必需的矿物原材料。文章阐述了以广东梅州兴宁高岭土为分析对象,采用化学分析法测定高岭土中SiO2、Al2O3这2种化学成分的含量。结果表明,此高岭土纯度高,能满足市场需求,具有开发利用前景,适用于造纸、搪瓷、陶瓷和涂料工业用矿物原料。     

Sintering and characterisation of ceramics containing paper sludge, glass cullet and different types of clayey materials

The present paper reports on the sintering behaviour of several ceramics prepared using a previously selected mixture of incinerated paper mill sludge and glass cullet in the ratio 60/40 which was blended with 10, 20, 30 and 40 wt.% of three different natural materials. The three natural products were: a red quartzitic clay, a yellow quartzitic clay and a kaolin. All mixtures were blended by attrition milling and dried; powders were sieved, pressed into specimens and fired for 1 h at temperatures ranging from 1040 to 1140 °C. The resulting materials were characterized by water absorption, shrinkage, crystallographic composition, microstructure and physico-mechanical properties. It was observed that materials containing kaolin display the best overall behaviour independently of the quantity of kaolin introduced. Conversely the optimal sintering temperature, and consequently the best properties of the materials prepared using red or yellow clay were measured on products fired at temperatures above 1080 °C; materials and temperatures are affected by the amount of clay added.     

Technology for producing large dense kaolin blocks

Conclusions The Ukrainian Scientific-Research Institute of Refractories has developed the main technical parameters for obtaining dense kaolin products with relatively moderate specific pressing pressures (about 500 kg/cm²), The Podol'sk Refractories Plant produced an experimental batch of kaolin blocks with a porosity of less than 12% based on chamotte made from Novoselitsk kaolin. The main properties of the kaolin blocks are better than those required by GOST for brick class-A produced for blast furnaces, and correspond to the properties of dense kaolin blast furnace brick.Translated from Ogneupory, No. 6, pp. 2–6, June, 1971.     

壳聚糖接枝聚丙烯酸钠/高岭土复合树脂的吸水性能

利用溶液聚合法制备了壳聚糖接枝聚丙烯酸钠/高岭土复合树脂,研究了复合树脂在蒸馏水中的吸水速率、重复吸水性能和人工尿液中的吸水倍率,以及在不同温度、不同电解质溶液离子强度和不同pH值的环境下复合树脂的吸水性能。结果表明,复合树脂的吸水速率较慢,在多次重复吸水后吸水性能也逐渐降低,在人工尿液中的吸水倍率高于聚丙烯酸钠树脂,低于壳聚糖接枝丙烯酸钠树脂;随着温度的升高,复合树脂的吸水能力增强,超过50℃后变化较小;树脂的吸液倍率随着电解质溶液浓度和价态的增大而下降;随着pH值的增大而出现驼峰,在pH=3.5和pH=8.5处分别出现吸液倍率最大值。     

Comparison of the physicochemical properties and mineralogy of Chinese (Beihai) and Brazilian kaolin

Beihai area (China) has about 500 million tons kaolin reserves with potential applications in ceramics, paint, plastic and rubber-filler industries, but unlike the Brazilian kaolin, it is not good in paper-coating industry. In order to understand the differences between Chinese (Beihai) and Brazilian kaolin, their individual physicochemical properties, morphologies, crystal structures, and surface characteristics were systematically investigated and compared. The results showed that the viscosity concentration, specific surface area and zeta potential of Brazilian kaolin were higher than those of Beihai kaolin. SEM and TEM images revealed that Brazilian kaolin had more regular particle shape, smoother surface and larger diameter–thickness ratio than those of Beihai kaolin. Moreover, XRD and TG/DSC analyses exhibited that Beihai kaolin was low ordered kaolinite with lower value of Hinckley index, average flake thickness along c-axis and endothermic peak temperature as compared to Brazilian kaolin. Furthermore, the crystal structures refined by the Rietveld method of Beihai kaolin showed a greater distortion of [SiO₄] tetrahedron than that of Brazilian kaolin. It can be concluded that low viscosity concentration, low degree of order, and irregular particle shape of Chinese (Beihai) kaolin are the reasons why it is not suitable for use in the paper-coating industry.     

Concentrated Kaolin from the Zhuravlinyi Log Deposit for Ceramic Production

It is demonstrated that the method of dry concentration of kaolin from the Zhuravlinyi Log deposit implemented at the Plast-Rifei Company makes it possible to separate kaolin products of different degrees of dispersion and by mixing them in a certain ratio to control the dispersion, the quality, and the ceramic properties of concentrated kaolin, taking into account the requirements of a particular ceramic production.     

Technical properties of compounded kaolin sample from Griva (Macedonia, Greece)

The purpose of this paper is to establish the possible industrial applications of Griva kaolin. This kaolin comes from the alteration of gabbroic rocks from the Griva area, Macedonia, Greece. Mineralogically, the kaolin is composed mainly of kaolinite associated with vermiculite and plagioclases, and traces of quartz, amphiboles, halloysite and smectites. The kaolin grain-size analysis shows that the kaolin is mostly finer than <20 μm with 20% of <2 μm. The amounts of Fe, Mg and Ca for the < 20 μm fraction are higher than those of standard commercial kaolins. The kaolinite is disordered with low crystallinity. Kaolinite crystals do not present typical pseudohexagonal stackings, showing irregular morphology, and vermicular aggregates booklets. The Brookfield viscosity of about 450 cp (at 70% solids 12 rpm), the high brightness (83% on < 20 μm fraction) and the dispersability in water suspensions would favour its use as filler in the paper and paint industries. However, the low crystallinity kaolinite precludes its use as filler in rubber industry. The kaolin shows a liquid limit of about 48% and a plastic limit of 34%. The firing characteristics indicate its possible use as a ceramic raw material for stoneware and sanitary ware products.     

Synergistic effect of talc/calcined kaolin binary fillers on rigid PVC: Improved properties of PVC composites

This study aims to develop poly(vinyl chloride) (PVC) composites prepared by melt mixing by using a combination of talc and calcined kaolin as filler in order to improve the disadvantages of rigid PVC, which is widely used in industry, such as poor mechanical properties and low thermal stability. In addition, PVC/talc and PVC/calcined kaolin composites were also examined for comparison. The calcined kaolin is modified with urea to increase the surface area (chemical treatment), while the surface of both fillers is coated with stearic acid for good compatibility with PVC (mechanical treatment). Scanning electron microscopy micrographs showed homogeneous distribution of mechanically processed fillers. Attenuated total reflectance–Fourier-transform infrared spectroscopy analysis revealed successful coating of the fillers with stearic acid. Also, new bands were detected in the spectrum of urea-treated calcined kaolin, showing an effective chemical treatment. It has been observed that the treatment of fillers improves the mechanical properties of PVC. Thermogravimetric results showed that delaminated calcined kaolin increased the thermal stability of PVC composites. The results of this study proved that binary filler composites combine good properties of both (synergistic effect) and good filler dispersion can be obtained by using stearic acid and urea.     

Kaolin from Zhuravlinyi Log Deposit for Ceramic Production

A kaolin concentrate is proposed for various sectors of the industry, including the ceramic sector. The company takes extensive measures to stabilize the technological properties of kaolin concentrates.__________Translated from Steklo i Keramika, No. 1, pp. 23 – 24, January, 2005.     

大洲高岭土矿物组成和深加工试验研究

系统介绍了大洲高岭土矿的地质概况，矿床特征，对大洲高岭土的理化性能进行了深入研究并对其进行了深加工试验研究试验结果表明：大洲高岭土是一种结晶较差的高岭石，工艺性能一般．Ｆｅ２Ｏ３含量在１．２％－２％，经深加工可降低Ｆｅ２Ｏ３含量．一般可以达到陶瓷工业用高岭土的一、二级标准，为陶瓷工业产品高档化创造了物质条件。     

塑料用矿物填料

以云母、硅灰石、碳酸钙、滑石、高岭土、水合矾土、重晶石、硅石粉等工业矿物作为塑料的填料,可以降低塑料制品的成本,改善塑料制品的性能。本文论述了矿物填料的作用、影响因素、价格效应,以及矿物填料加工的技术问题,并探讨了我国塑料用矿物填料的工业发展的前景。     

Sintering of magnesia refractories through the formation of periclase–forsterite–spinel phases

Effect of calcined kaolin additions on sinterability of dead-burned magnesia was studied through additions of Egyptian kaolin. Five batches containing powders of 100/0, 90/10, 80/20, 70/30 and 60/40 magnesia/kaolin, respectively, were mixed, dried and fired up to 1550 °C for 4 h. Their physical (bulk density and apparent porosity), mechanical (cold crushing strength) as well as refractory (thermal shock resistance and refractoriness under load) properties were tested according to the International Standard Specifications. The phase compositions of the fired batches were investigated using X-ray diffraction as well as scanning electron microscope to illustrate the effect of the different developed phases on the above properties compared with the main magnesia source itself. Generally, samples containing 10–20 wt.% kaolin are characterized by their high sintering, mechanical and refractory properties, so they are recommended for use as a lining for different parts of steel furnaces as well as heating zone of cement rotary kilns. Samples containing 30–40 wt.% kaolin with lower refractory properties can be used in the heat exchangers or as kiln furniture in ceramic industries.     

The influence of kaolin and calcined kaolin on SBR composite properties

Kaolin is a naturally abundant and cheap ore, which can impart various properties to rubber composites besides lowering its cost. In this work, kaolin and thermally treated kaolin (especially m‐kaolinite), which is the most active species of kaolin were added to styrene–butadiene rubber composites in different concentrations ranging between 10 and 50 phr to study their effect on SBR rheometric, physical, mechanical, and thermal properties. The main aim of this study was to state whether the activity of calcined kaolin will allow it to work as a bifunctional additive (i.e., reinforcing filler and accelerator) or an adverse one (i.e., working as an active radical breaking the polymer chains). The study revealed that SBR containing calcined kaolin performed better properties than those containing kaolin indicating that calcined kaolin worked as a bifunctional additive in SBR composites. POLYM. COMPOS., 35:570–580, 2014. © 2013 Society of Plastics Engineers