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1.
综述了国内外解聚废旧硅橡胶生产硅氧烷(或硅烷),部分解聚制取胶料以及粉碎剂硅橡胶微粉等方面的技术进展。  相似文献   

2.
一种表征连续混炼机分散混合能力的方法   总被引:1,自引:0,他引:1  
通过对混炼过程中附聚体解聚过程的分析,提出了两个描述混炼流场解聚能力的参数——解聚能量密度和描述混炼解聚效果的参数——平均解聚功.并运用该参数对混炼过程和混炼特性进行了表征,结果表明,解聚能量密度较好的表征了混炼流场熔体解聚能力的大小,而平均解聚功则可以直接表征混炼流场对共混物中颗粒的解聚效果.  相似文献   

3.
介绍了国内外开发的聚对苯二甲酸乙二醇(酯PET化)学解聚的工艺方法,包括水解法、甲醇解聚法、乙醇解聚法、乙二醇解聚法等,对主要的化学解聚方法的优缺点进行了综合比较,指出我国应该加强PET解聚技术的研究以,彻底解决资源紧张和白色污染问题。  相似文献   

4.
通过化学法对废旧涤纶纺织品进行解聚,在解聚后重新利用,实现废旧涤纶纺织品永久循环利用。从原料的收集与处理、解聚原理、解聚过程、影响解聚反应的因素等方面对废旧涤纶纺织品化学解聚工艺进行了探讨。  相似文献   

5.
采用高温固相合成法成备了SnO2.2ZnO复合金属氧化物,对催化剂及解聚产物进行了表征,并对其在微波条件下对PET解聚的催化作用进行了研究,锌锡复合氧化物对PET的解聚有较好的催化作用。同时我们采用正交实验方法研究了微波作用下SnO2.2ZnO催化解聚PET的最佳反应条件。通扫描电镜分析微波辐射PET的催化解聚残留物,我们发现微波作用下PET解聚过程是从PET的内外部同时发生的。  相似文献   

6.
以课题组独创的催化剂添加方式,实现了对煤的催化解聚.研究了锌基催化剂对内蒙褐煤催化解聚产物分布的影响.结果表明:催化解聚对产物的分布影响显著.相比原煤热解,催化煤解聚焦油产率提高26.88%,煤气热值提高30.79%,半焦比表面积提高80.65%.催化煤解聚相比原煤热解显示出一定的潜在优越性.  相似文献   

7.
木质纤维生物质作为地球上最丰富的可再生资源, 不仅储量巨大而且在利用过程中具有碳平衡的显著优势, 已逐渐成为最具发展前景的可再生能源之一。木质纤维中的木质素是自然界最大且唯一的可再生芳香族化合物原料, 在生物质燃料转化, 尤其是解聚生产苯系化工产品等领域具有极为重要的作用和意义。本文在简述木质素化学结构的基础上, 综述了近年来木质素高温热解聚, 生物酶解聚, 催化热解聚, 光催化解聚和溶剂热解聚等解聚方法, 深入分析了液相催化过程中酸、碱催化体系, 加氢和氧化催化体系的机理及优缺点, 总结了现阶段木质素解聚方法中存在的问题, 并对未来的发展方向进行了展望。  相似文献   

8.
聚对苯二甲酸乙二醇酯在超临界甲醇中解聚的研究   总被引:6,自引:1,他引:6  
在间歇高压反应器中研究了聚对苯二甲酸乙二醇酯(PET)在超临界甲醇中的解聚反应特性, 通过扫描电镜观测了不同解聚条件下固相聚合物的内部结构,提出了解聚反应历程并得到了不同解聚条件下反应表观活化能。在甲醇的非临界区域,PET在甲醇中表现为溶胀过程,解聚程度低,反应在聚合物表面进行,反应表观活化能为27.19kJmol-1,解聚过程为传质、扩散控制;在甲醇的临界区域, PET完全溶于甲醇,解聚反应在均相中进行,反应表观活化能为89.79kJmol-1,为化学反应控制。  相似文献   

9.
以醋酸锌(ZnAc2)为催化剂,甲醇(CH3OH)为醇解剂,采用在线红外光谱仪跟踪了聚对苯二甲酸乙二醇酯(PET)解聚反应过程中产物红外特征峰强度随时间的变化关系,研究了催化剂用量和反应温度对PET解聚过程的影响,并给出了可能的解聚机理。红外光谱跟踪结果表明,解聚过程中C-O,C=O基团的红外吸光强度随时间不断增强,解聚完成后吸光强度趋于定值。同时二者表现出相同的变化趋势,可以用其表征PET的解聚率。通过比较不同反应条件下的PET解聚速率发现,催化剂ZnAc2的适宜用量为PET质量的0.8%;提高反应温度可显著缩短PET解聚所需的时间,在190℃条件下,PET完全解聚仅用时15 min,具有良好的工业应用价值。PET解聚的主要产物是对苯二甲酸二甲酯(DMT)和乙二醇(EG),解聚过程中PET存在多种断链机制,产生不同的中间产物,可继续与甲醇发生酯交换反应生成DMT和EG。  相似文献   

10.
双环戊二烯的新型分解法   总被引:8,自引:0,他引:8  
马黎明  杨正银 《化学世界》1992,33(10):471-474
本文报道了一种双环戊二烯的新型解聚法,该方法把管式裂解的先进手段引入到双环戊二烯解聚中。先将原料汽化,再使其通过高温管道、在汽态下高温解聚。克服了常规液态解聚时温度难于超过双环戊二烯沸点的限制,可把解聚温度提高到330℃左右,从而大大提高了解聚速率和单环产率,此外由于采用了解聚分馏同步进行的办法,总计可提高速率4倍,节能50%。生产实践证明这种方法稳定可靠,具有很好的推广应用价值。  相似文献   

11.
The mineralogy of coal and coal ash samples from a wide variety of deposits worldwide has been studied by X-ray diffractometry, light microscopy, SEM, TEM, and DTA-TGA methods. The common major minerals identified in the crystalline matter of coals are quartz, kaolinite, illite, calcite, pyrite, plagioclase, K-feldspar and gypsum, and occasionally dolomite, ankerite, siderite, Fe oxyhydroxides and sulphates. A number of minor and especially accessory minerals are also present. The modes of occurrence and some genetic peculiarities of the minerals found are described and summarized. Minerals and phases of probable detrital origin include mainly silicates, volcanic glass, oxyhydroxides and phosphates. Authigenic minerals of syngenetic origin may be sulphides, clay minerals, carbonates and rarely sulphates and phosphates. Epigenetic minerals, formed by the infiltration of low-temperature hydrothermal solutions, may include sulphides, carbonates, sulphates, clay minerals, quartz, chlorides, and probably alkaline-earth hydroxides and zeolites. The alteration products of detrital and authigenic minerals may be Fe and Al oxyhydroxides, sulphates, kaolinite, illite, chlorite, muscovite, zeolites and calcite. The behaviour of these minerals and phases during low- and high-temperature ashing is also discussed.  相似文献   

12.
Shifeng Dai  Dexin Han 《Fuel》2006,85(4):456-464
Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 μg/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation.  相似文献   

13.
介绍近年来我国橡胶防老剂和促进剂进出口情况。2013年,我国防老剂和促进剂进口量分别为19046.61 t和14984.44 t,同比分别增长16.12%和11.64%;进口金额分别为6202.02万美元和7391.97万美元,同比分别增长14.76%和1.39%;出口量分别为29070.40 t和89942.59 t,同比分别增长62.68%和45.72%;出口金额分别为6794.43万美元和27885.34万美元,同比分别增长60.45%和50.17%。我国进口防老剂主要来自中国大陆(以国货复进口形式进口)、美国、韩国以及中国台湾省等,进口促进剂主要来自中国台湾省、美国、韩国、日本以及德国等,防老剂主要出口日本、泰国、印度尼西亚和韩国等,促进剂主要出口美国、韩国、巴西、泰国和日本等。  相似文献   

14.
The catalyst comprised of triisobutylaluminum, zinc acetylacetonate, and water was used to prepare homopolymer of epichlorohydrin; copolymers of epichlorohydrin with propylene oxide, ethylene oxide, and allyl glycidyl ether; and terpolymers of epichlorohydrin, propylene oxide, and allyl glycidyl ether and of epichlorohydrin, ethylene oxide, and allyl glycidyl ether. The vulcanizates of these rubbers provide variations of stressstrain and dynamic properties, freeze point, hardness, and solvent resistance depending on the type and amount of comonomer. In general, these rubbers have excellent heat, ozone, and oxidation resistance as well as oil and solvent resistance.  相似文献   

15.
Minerals are widely used in the pharmaceutical industry as lubricants, desiccants, disintegrants, diluents, binders, pigments and opacifiers, as well as emulsifying, thickening, isotonic agents, and anticaking agents, and flavour correctors and carriers of active ingredients.A variety of minerals are used as excipients in pharmaceutical preparations because they have certain desirable physical and physico-chemical properties, such as high adsorption capacity, specific surface area, swelling capacity, and reactivity to acids. Other important properties are water solubility and dispersivity, hygroscopicity, unctuosity, thixotropy, slightly alkaline reaction (pH), plasticity, opacity, and colour. Clearly such minerals must not be toxic to humans. The following minerals are commonly used as excipients: oxides (rutile, zincite, periclase, hematite, maghemite, magnetite), hydroxides (goethite), carbonates (calcite, magnesite), sulfates (gypsum, anhydrite), chlorides (halite, sylvite), phosphates (hydroxyapatite), and phyllosilicates (palygorskite, sepiolite, kaolinite, talc, montmorillonite, saponite and hectorite). More recently, some tectosilicates (zeolites) also feature in pharmaceutical preparations.Minerals also enjoy the following medical/health applications: a) contrast diagnostic techniques, b) production of dental cements and dental molds in odontology, c) immobilization of limbs and fractures or dental and craniofacial surgical procedures in traumatology, d) bone grafts or construction of orbital implants, and e) spas and aesthetic centers. Examples of such minerals are oxides (zincite, magnetite and maghemite), sulphates (gypsum and barite), phosphates (hydroxyapatite) and phyllosilicates (clay minerals).  相似文献   

16.
几种杀虫剂对草坪害虫的控制效果   总被引:6,自引:0,他引:6  
李有志  马骏  黄继光  徐汉虹  文礼章 《农药》2006,45(8):561-564
测定了绿僵菌、毒死蜱、辛硫磷等药剂对草坪害虫的控制效果。结果表明绿僵菌、毒死蜱和辛硫磷都是防治草坪地下害虫的有效药剂,毒死蜱和辛硫磷还能有效防治草坪茎叶害虫禾灰翅夜蛾和斜纹夜蛾等。药后45d,绿僵菌对铜绿丽金龟幼虫蛴螬的防效和对地下害虫的总防效分别为91.2%和87.6%。绿僵菌对茎叶害虫的防效较差,药后3、7、10d时,对禾灰翅夜蛾的防效分别为3.7%、9.2%和18.9%;对茎叶害虫的总防效在12.2%以下。辛硫磷和毒死蜱药后3d对禾灰翅夜蛾的防效分别是93.7%和97.6%;对茎叶害虫的总防效分别是92.0%和93.6%。当高效氯氰菊酯分别和辛硫磷、毒死蜱混用防治斜纹夜蛾时,防效更高、速效性更好。  相似文献   

17.
This article summarizes and reviews the various preparation methods, physical properties, and potential applications of one-dimensional nanostructures of conjugated polyaniline (PANI), polypyrrole (PPY) and poly(3,4-ethylenedioxythiophene) (PEDOT). The synthesis approaches include hard physical template method, soft chemical template method, electrospinning, and lithography techniques. Particularly, the electronic transport (e.g., electrical conductivity, current-voltage (I-V) characteristics, magnetoresistance, and nanocontact resistance) and mechanical properties of individual nanowires/tubes, and specific heat capacity, magnetic susceptibility, and optical properties of the polymer nanostructures are presented with emphasis on size-dependent behaviors. Several potential applications and corresponding challenges of these nanofibers and nanotubes in chemical, optical and bio-sensors, nano-diodes, field effect transistors, field emission and electrochromic displays, super-capacitors and energy storage, actuators, drug delivery, neural interfaces, and protein purification are also discussed.  相似文献   

18.
松香是一类产量丰富、价格低廉的可再生林产资源,被广泛地应用于食品、农业、橡胶、油墨、涂料等领域。松香的三环二萜结构具有超强的疏水性,通过催化异构、Diels-Alder加成等手段引入亲水基团可制备高附加值、易生物降解的绿色表面活性剂。本文从阴离子、阳离子、非离子和两性离子表面活性剂4个大类对松香基表面活性剂应用的文献及专利进行综述,重点分析了羧酸盐、磺酸盐、硫酸盐和磷酸盐4种阴离子型表面活性剂和季铵盐阳离子型表面活性剂,多元醇型和聚氧乙烯型非离子表面活性剂,以及甜菜碱型和氧化胺型两性离子表面活性剂。剖析松香基表面活性剂产业化开发的新技术及新产品概况,提出松香基表面活性剂替代传统表面活性剂的潜在应用领域。同时,对松香基表面活性剂的研究发展与产业化发展进行了评价与展望。  相似文献   

19.
1993—1994年国外塑料工业进展   总被引:4,自引:0,他引:4  
介绍1993~1994年国外塑料工业进展.提供了美国、日本、原联邦德国、原苏联、法国、意大利、英国、韩国等生产国及亚洲、西欧(包括共同市场国家和奥地利、芬兰、挪威、瑞士和瑞典)、东欧、北美、中南美、非洲和大洋洲等地域的塑料材料产量.按通用热塑性树脂(包括聚乙烯、聚丙烯、聚苯乙烯、ABS和聚氯乙烯)、工程塑料(包括尼龙、聚碳酸酯、热塑性聚酯、聚甲醛和改性PPO/PPE)、热固性树脂(包括酚醛、聚氨酯、不饱和聚酯和环氧树脂)、特种工程塑料(包括聚苯硫醚、液晶聚合物、聚醚砜、聚醚醚酮和聚芳酯)和硅树脂、丙烯酸树脂等.对塑料材料产量和消费、合成工艺、产品应用开发、树脂品种延伸等进展作了详尽介绍.  相似文献   

20.
降低石膏综合利用能耗与投资的措施   总被引:1,自引:0,他引:1  
吕天宝 《贵州化工》2010,35(6):14-16,24
根据多年实践研究针对石膏分解反应机理及特点,分析了石膏(特别是工业石膏废渣)生产硫酸与水泥在各工序的能耗及投资,尤其是在烘干、分解、煅烧中的热耗进行了详细分析;剖析了原料成分、热耗与SO2浓度、投资的关系;提出了降低能耗和投资的途径办法;指出了在使用、设计及工艺选择中注意的问题;以年产200kt规模为例提出消耗、成本、投资、技术经济数据,说明该技术的先进性和推广价值。  相似文献   

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