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51.
分析了煤气中氰化氢的形成,论述了氰化氢在煤气和其冷凝液中的平衡机理,讨论了影响氰化氢相平衡的因素,研究了直接终冷、间接终冷时煤气中氰化氢的转移情况。  相似文献   
52.
不同活化剂对石油焦基活性炭孔结构的影响   总被引:4,自引:1,他引:4  
以石油焦为原料 ,Na OH,KOH和 Na2 CO3 为活化剂制备活性炭 ,采用氮气吸附考察了不同活化剂对活性炭的比表面积、中孔和微孔孔径分布、孔容积及平均孔径等孔结构的影响 .结果表明 :KOH活化制备的活性炭包含 1 nm的微孔和 4nm的中孔 ,总孔容 0 .648cm3 /g,比表面积大 ;Na OH制备的活性炭以 1 nm的微孔为主 ,占总孔容 ( 0 .1 65 cm3 /g)的 98% ,平均孔径 1 .83nm;Na2 CO3 制备的活性炭以 4nm的中孔为主 ,占总孔容 ( 0 .1 43cm3 /g)的 68.5 % ,平均孔径 3.42 nm,比表面积小 .3种样品的孔径都呈现出多峰分布特征 .KOH和 Na2 CO3 活化制备的活性炭的 N2 吸附脱附曲线属于 型 ,Na OH活化制备的活性炭吸附脱附曲线属于 型 .  相似文献   
53.
An examination of the influence of pressure and heating rate on the thermoplastic properties of a weakly coking coal and of coal with various pitch-like additives was carried out using a high pressure dilatometer. Pressure up to 4 MPa markedly increased the swelling properties and increased the plastic range by decreasing the softening temperature, but the effects of pressure were strongly influenced by rate of heating with high heating rates enhancing the effects. Additions of tar or pitch also enhanced swelling at low pressure. The solid carbonization residues from the dilatometer were examined by polarized light microscopy to determine the content and composition of optically anisotropic species. The anisotropic content was increased by increases in pressure and heating rate and pitch additives enhanced the anisotropic content, especially at low pressure, without affecting the composition of the anisotropy. No direct correlations exist between the dilatometric parameters and the optical anisotropy but their dependence on the conditions emphasizes that when considering high pressure gasification of coal, it is necessary to obtain data under appropriate conditions.  相似文献   
54.
雒和明 《粘接》2007,28(3):10-12
分析了热压成型及冷压成型方法的优劣。选择增强剂、固化防水剂等添加剂对水玻璃粘合剂进行改性,研究了添加剂对型焦性能的影响。实验结果表明,焦粉成型添加剂加入量为:水玻璃粘合剂12%,增强剂0.2%,固化防水剂0.3%,成型焦球生(干)型焦落下强度、生(干)型焦压缩强度、耐水性、热稳定性、反应活性等性能可满足工业生产的工艺要求。  相似文献   
55.
Summary: A semi‐batch process using nitroxide mediated polymerization, was explored for the design of low molecular weight solvent‐borne coatings, typical of those used in the automotive industry. While living radical polymerization (LRP) offers many advantages in the control of polymer chain microstructure that may confer important physical and chemical property benefits to coatings, adapting LRP to a semi‐batch process poses significant challenges in the design and operation of the process. Using styrene monomer, various two‐component initiating systems (free radical initiator, 4‐hydroxy‐TEMPO) were studied to understand the effects of different initiators on the course of polymerization. In addition, an alkoxyamine was synthesized and used as the initiating source. The initiators Luperox 7M75 and Luperox 231 give higher polymerization rates and reasonable control over polymerization, while benzoyl peroxide (BPO), Vazo 67, and the alkoxyamine are less effective. The number of polymer chains in the final product is always less than the theoretical value, reflecting poor initiation efficiency, probably resulting from undesirable termination reactions that become important due to the nature of the semi‐batch process. Adding camphorsulfonic acid (CSA) or charging initiator concurrently with monomer during semi‐batch feed, can increase the polymerization rate while maintaining the living character of the polymerization. The copolymerization of styrene and butyl acrylate is also shown to exhibit living character.

Schematic representation of the exchange reaction to produce N‐TEMPO capped polymer chains.  相似文献   

56.
Using low-rank coals, the modifying activities of some petroleum, coal tar and aromatic hydrocarbon additives have been examined to find procedures for their utilization in the preparation of blast furnace coke. Petroleum pitch, especially after hydrogenation, exhibited excellent modifying activity even with non-fusible coals. In contrast, the activity of coal tar was very limited with such coals. The napththenic component, revealed by n.m.r. of the additives, appears to be important in the co-carbonization by inducing fusibility and anisotropic development in such coals. Co-carbonization to recover the dehydrogenated additives was attempted. However, there was no development of the anisotropy in the resultant coke by dissolution of the coal particles although the coal particles were firmly fixed in the matrix. Acid-refluxing treatment of non-fusible coals was found to enhance their modification susceptibility, indicating that some of the acid-soluble mineral matter is important in the thermal depolymerization or fusion process of the coal.  相似文献   
57.
赵光明  李斌  晋日亚 《煤化工》2006,34(4):26-28
本课题以6m焦炉为例,分析了装煤逸出烟尘的来源,计算了焦炉装煤逸出烟尘量,在检测装煤焦炉逸出烟尘主要成分浓度的基础上,计算了主要污染物的释放总量,并对计算结果进行了分析,可为工程治理提供有用的参考数据。  相似文献   
58.
对废塑料配煤炼焦产品产率的研究   总被引:2,自引:1,他引:2  
通过在炼焦煤中添加不同种类、不同比例的废塑料,研究了所得焦炭的性质和焦化产品产率的变化。实验结果表明,焦油和焦炭的产率随着废塑料添加比例的增加而增大,粗苯和氨等产率变化不明显。  相似文献   
59.
朱道藩 《煤化工》1997,(4):12-18
本文论述了国内外高炉喷煤技术的发展,以及对炼焦工业的影响,最后,展望了我国高炉喷煤技术发展的前景。  相似文献   
60.
David Merrick 《Fuel》1983,62(5):567-570
A mathematical model to predict the strength of a coke manufactured from a blend of coals is proposed. The model operates in terms of ‘bond strengths’ between the constituents. The magnitudes of these bond strengths may be determined from the strengths of cokes manufactured from the individual constituents and from a limited number of binary blends. The model has been applied to predictions of the M10 index of coke strength for binary and ternary blends, and the predictions are in reasonable agreement with the experimental data. In particular, the model is able to account for the behaviour of incompatible coals and bridging coals in blends.  相似文献   
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