Al-MCM-48中Al含量对高密度聚乙烯催化裂解的影响

本文用常温合成方法合成了不同硅铝比的Al-MCM-48,并研究了硅铝比不同对Al-MCM-48催化裂解高密度聚乙烯(HDPE)的影响.发现Al-MCM-48存在的催化裂解可以提高HDPE的转化率和液体收率;硅铝比的变化对转化率和液体收率有较明显的影响,转化率和液体收率随硅铝比的增加而增加,当硅铝比达到100时达最大值,然后液体收率和转化率开始逐步下降;液体产物中的烯烃的含量随硅铝比的增加而增加;重复实验表明Al-MCM-48具有较好的稳定性,不易结焦.     

胶液法制备高顺式端羟基聚丁二烯液体橡胶

以工业顺丁胶原液为起始原料,先经氧化裂解反应制得醛基封端的聚丁二烯液体橡胶,再经还原反应制得了端羟基聚丁二烯液体橡胶.结果表明,反应过程中顺丁胶的微观结构未发生异构化,所得的端羟基聚丁二烯液体橡胶的顺式含量高(cis-1,495%);分子量通过控制氧化裂解反应物与丁二烯结构单元的化学计量比,在2200~7000间可调(~1H-NMR法);分子量分布指数维持在1.5~2.1范围;官能度(fn)在2.0左右.与阴离子聚合型丁羟胶和自由基聚合型丁羟胶相比,氧化裂解法制备的丁羟胶微观结构更规整,顺式含量更高,能够保持极低的玻璃化转变温度.此外,以工业顺丁胶原液为原料,既省去了顺丁块胶生产的水析凝聚、干燥压块等过程,又免去了胶块剪切破碎、溶胀溶解等过程,大幅度减少了能量消耗,且反应条件温和、可控、高效、经济,具有良好的工业化前景.     

双烯类液体橡胶的研发进展

液体橡胶作为合成橡胶的重要种类,是室温下能流动的橡胶材料。本文介绍了液体橡胶的性能特点及分类,着重阐述了双烯类液体橡胶即液体聚丁二烯橡胶、液体丁腈橡胶、液体异戊橡胶、液体丁苯橡胶和液体氯丁橡胶的结构特征、性能特点及主要用途,并进一步探讨了它们的研发、生产和使用情况。液体橡胶便于实现生产连续化和自动化,且加工方便,顺应时代发展的"低碳"潮流。从产品种类、牌号,应用范围等方面对今后的发展提出了建议。     

十氢萘气相氧化裂解制低碳烯烃的研究

十氢萘气相氧化裂解（GOC）与传统的热裂解工艺相比，O2的存在降低了十氢萘GOC反应的活化能，使反应在较低温度下具有高的反应性能；O2同时起到消除积炭的作用，提高体系的抗积炭能力。十氢萘GOC反应在较低温度下即可获得较高的液体收率；高温下由于十氢萘裂解深度较高，低碳烯烃收率可高于液体收率，在所得的液体中，芳烃，尤其是BTX（苯、甲苯和二甲苯）占主要部分。十氢萘GOC反应制备低碳烯烃的适宜反应条件为，700℃~800℃，停留<0.4s，烷氧摩尔比0.3~0.5，空气可代替纯氧进料。800℃，烷氧摩尔比0.5，停留0.4s，可获得37％左右的低碳烯烃收率和50%左右的液体收率（BTX收率为29％）。     

改性ZSM-5分子筛催化裂解湛江等鞭金藻制取低碳烯烃(英)

研究了湛江等鞭金藻(Isochrysis zhanjiangensis)在改性ZSM-5分子筛上催化裂解制取低碳烯烃的过程.与热裂解过程相比,湛江等鞭金藻催化裂解可以得到更高的低碳烯烃选择性和收率.同时还研究了湛江等鞭金藻中不同油脂和藻渣的催化裂解.结果表明,微藻中的油脂能有效转化为烯烃,其中中性脂的烯烃收率最高,可达36.7%.不同溶剂抽提后得到的藻渣也可转化为低碳烯烃,但收率远低于微藻中的油脂.微藻中的油脂,特别是中性脂,是烯烃的主要贡献者,提高微藻中的中性脂含量能够得到更高的低碳烯烃收率.     

生物质焦油的催化裂解研究

对稻壳热解过程中产生的焦油进行了催化裂解研究。实验装置主体由裂解炉和固定床催化裂解反应器组成。研究得出催化裂解条件（温度、停留时间等）对焦油脱除的影响规律，并分析了生物质焦油催化裂解过程中发生的反应和焦油催化裂解机理。研究表明，白云石对焦油的催化裂解有较好的效果，随着温度和停留时间的增加，其催化裂解率提高。     

裂解色谱法研究环化顺—1,4—丁二烯—异戊二烯无规共聚物

如同顺-1,4-聚丁二烯(PBd)和聚异戊二烯(PIP),在一定的催化条件下,顺-1,4-丁二烯-异戊二烯无规共聚物(PBI,简称丁戊无规共聚物)可生成环化顺-1,4-丁戊无规共聚物(CP-BI)。作者曾报道用裂解色谱法表征环化顺-1,4-聚丁二烯(CPBd),本文对不同组成的CPBI和PBI进行了裂解色谱比较研究。 表1所列试样由实验室合成。用CDS pyro-probe 190型裂解器,SP-2305E型气相色谱仪,FID。裂解温度700℃,裂解时间5秒,色谱柱4mm×3m不锈钢柱,填充20%SE-30固定相(101白色担体),柱温106℃,载气氮气40mL/min。试样量约30μg,放于石英管内,后者再插入     

AlSi-ZSM-48沸石分子筛的合成及其催化性能

 考察了以廉价的1，6－己二胺为模板剂合成AlSi－ZSM－48沸石分子筛的条件及其在醚化碳四烯烃裂解生成丙烯和乙烯反应中的催化性能．结果表明，合成体系的碱度和盐类的加入对AlSi－ZSM－48沸石的合成影响极大，n（OH－）／n（Si）大于0．15时得不到AlSi－ZSM－48沸石，盐类如NaF和NaCl等的加入会抑制AlSi－ZSM－48的生成，而更利于ZSM－5等杂晶的产生．在醚化碳四烯烃的裂解反应中，AlSi－ZSM－48表现出优越的催化性能，可以得到高收率的丙烯和乙烯，两种烯烃的总收率可达40％以上     

固体酸催化剂对LDPE与PS混合物催化裂解行为的研究

研究ZSM—G5和USY，及新型改性催化剂DeLaZSM-5对LDPE与PS混合聚烯烃的催化裂解行为，与热裂解相比，ZSM-5与DeLaZSM-5使裂解速率增加、残渣收率降低、产品分布变窄，而USY使裂解活性降低，其中De-LaZSM-5对LDPE／PS混合物具有最高的催化裂解活性。     

钨酸钠/冰乙酸/过氧化氢作用下聚丁二烯橡胶环氧化及降解行为研究

本文研究了在钨酸钠/冰乙酸/过氧化氢催化体系作用下聚丁二烯橡胶环氧化及降解行为.采用红外(FT-IR)、核磁(1H-NMR)和气相凝胶渗透色谱(GPC)对降解产物进行了表征,结果表明60℃反应24h,聚丁二烯橡胶环氧度为21.27％,而其分子量没有明显降低.     

Pyrolysis of waste tire on ZSM-5 zeolite with enhanced catalytic activities

Catalytic copyrolysis of waste tires over ZSM-5 zeolite with lubricant base oil (LBO) was undertaken at 430 °C under nitrogen atmosphere in a batch mode, and the pyrolysis oils were characterized using gas chromatography/mass spectroscopy (GC-MS). By combining with LBO, the ZSM-5 catalyzed pyrolysis system of tires has a sharply enhanced degradation rate. Compared to the pyrolysis without LBO, the liquid yield is increased from 33.6% to 48.0%, while the gas and the residue yields are decreased. In the pyrolysis oils, the content of heavy components is decreased and the content of light oils (n-C ≤ 12) is increased from 77.8%(without LBO) to 83.1%(with LBO); especially, the content of C₁₀ components has a sharp increase. Moreover, the liquid compositions are changed. Particularly, the percentage of limonene increased dramatically from 7.54% for thermal degradation to 13.58%. These results suggest that the enhanced catalytic effects on pyrolysis of tires in the catalytic systems are due to the improved interactions between tires and catalysts with the help of LBO. Therefore, it is possible to improve the process economics of scrap tires by catalytic copyrolysis with LBO, which can not only increase the pyrolysis rate remarkably but also produce high-value oil products.     

不同热裂解温度下ZSM-5对玉米秸秆催化热裂解烃类选择性影响

为探讨不同热裂解温度下ZSM-5对玉米秸秆催化热裂解特性及烃类选择性的影响,本研究利用TGA对比有无ZSM-5时玉米秸秆的热裂解失重曲线,利用Py-GC/MS对比玉米秸秆在450、500、550和600℃下的热裂解和催化热裂解产物分布。结果表明,ZSM-5的使用可以降低玉米秸秆最高分解速率时对应的热裂解温度,降低温度为23℃。未使用ZSM-5时,热裂解产物种类以及烃类选择性均随热裂解温度的升高不断增加,在600℃时,烃类选择性达到最高,为11.33%;使用ZSM-5后,烃类产率随热裂解温度的升高先增加后减少,在550℃时,烃类选择性达到最高,为29.24%。使用ZSM-5后,玉米秸秆催化热裂解主要产物中出现了甲苯、茚、萘、二甲基萘等烃类,甲苯的最高产率为4.76%,萘的最高产率为3.96%。     

改性合成橡胶在轮胎工业中的应用

介绍了几种合成橡胶的改性在轮胎工业中的应用现状。为了提高轮胎的综合行驶性能 ,近年来国外开发出了性能良好的溶聚丁苯、Nd系顺丁、乙烯基顺丁、3,4-异戊胶、卤化丁基胶、苯乙烯 -异戊二烯 -丁二烯橡胶、星型支化丁基胶及溴化三元乙丙胶等一系列改性合成橡胶新品种     

Aromatics and phenols from catalytic pyrolysis of Douglas fir pellets in microwave with ZSM-5 as a catalyst

Microwave assisted catalytic pyrolysis was investigated to convert Douglas fir pellets to bio-oils by a ZSM-5 zeolite catalyst. A central composite experimental design (CCD) was used to optimize the catalytic pyrolysis process. The effects of reaction time, temperature and catalyst to biomass ratio on the bio-oil, syngas, and biochar yields were determined. GC/MS analysis results showed that the bio-oil contained a series of important and useful chemical compounds. Phenols, guaiacols, and aromatic hydrocarbons were the most abundant compounds which were about 50–82% in bio-oil depending on the pyrolysis conditions. Comparison between the bio-oils from microwave pyrolysis with and without catalyst showed that the catalyst increased the content of aromatic hydrocarbons and phenols. A reaction pathway was proposed for microwave assisted catalyst pyrolysis of Douglas fir pellets.     

The effects of magnesium and aluminium ions’ additions on the kinetics of titanium dioxide structural transformation

Catalytic fast pyrolysis analysis of miscanthus over HZSM-5, La/ZSM-5, and Ca/ZSM-5 was performed using pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS). The characteristics of the catalysts used in this study were analyzed using XRD, SEM, Pyridine IR, ICP, and N₂ adsorption. The catalytic performance of the three catalysts was evaluated in terms of deoxygenation. Py–GC/MS results show that with increasing temperature, pyrolysis vapor yield first increased and then decreased. This may be due to secondary cracking at higher temperatures, which produced more gas products. Moreover, hydrocarbon content increased with rising temperature. The optimum temperature was found to be 600 °C, which resulted in the greatest liquid yield. All three catalysts increased pyrolysis vapor yield by about 30 %. Moreover, the hydrocarbon content of miscanthus increased from 6 to 39 %, 46, and 44 %, respectively, when HZSM-5, La/ZSM-5, and Ca/ZSM-5 were applied. In conclusion, the three catalysts were effective for deoxygenation of pyrolysis vapor yield. Considering both economic and catalytic upgrading effect, Ca/ZSM-5 may be the best catalyst.     

Comparison between the “one-step” and “two-step” catalytic pyrolysis of pine bark

In this study, one-step and two-step pyrolysis systems were compared in the pyrolysis of pine bark. One-step pyrolysis was performed in a fixed bed reactor with and without catalyst. Two-step pyrolysis was carried out in a dual reactor system over catalyst; the first reactor containing no catalyst whereas the second reactor containing catalyst to upgrade the thermally cracked products. The catalysts used in the pyrolysis systems were ReUS-Y, red mud and ZSM-5. In thermal pyrolysis, the pyrolysis system mainly affected the relative amount of bio-oil. The bio-oil yields obtained from two-step thermal pyrolysis were higher than the yields from one-step thermal pyrolysis. In the catalytic runs, ReUS-Y catalyst slightly decreased the char formation with a consequent increase in aqueous phase yield in the case of one-step pyrolysis. However, the catalysts decreased the bio-oil yield with a consequent increase in the gas yield in the case of two-step pyrolysis. The general compositions of bio-oils obtained from both two pyrolysis systems were affected by using catalysts. In the case of one-step pyrolysis, the formation of water and water soluble compounds were reduced by using ReUS-Y catalyst. In the case of two-step pyrolysis, both ZSM-5 and red mud increased the formation of water soluble compounds while they decreased water formation. In contrast, ReUS-Y decreased the formation of water soluble compounds and increased the amount of pyrolytic lignin compounds in bio-oil. Fuel characteristics of pyrolysis products (gas, bio-oil and char) for both two pyrolysis systems were also investigated comparatively.     

FCC轻汽油催化裂化生产丙烯反应规律的研究

在提升管实验装置和脉冲色谱装置上，采用ZSM-5催化剂，考察了不同条件下FCC轻汽油和2M1C5＝的裂化。结果表明,催化裂化过程添加ZSM 5催化剂可提高汽油中C5＝、C6＝的质量分数。轻汽油裂化生产丙烯的性能优于重汽油和全馏分汽油，在相对低的温度下瞬时反应能得到较高的丙烯收率。在脉冲色谱装置上，反应温度和载气流量对轻汽油和2M1C5＝裂化生产丙烯的影响一致，即反应温度升高，载气流量降低，丙烯收率增加。提高反应温度，延长停留时间可以提高丙烯对丁烯的比例。轻汽油在ZSM-5催化剂上反应，催化剂结焦失活速度开始较快，后来减缓。ZSM-5催化剂结焦失活对丙烯生成的抑制作用大于对丁烯的抑制作用，ZSM-5的强酸中心多则更有利于生成丙烯。     

Influence of the structural characteristic of pyrolysis products on thermal stability of styrene-butadiene rubber composites reinforced by different particle sized kaolinites

A series of rubber composites were prepared by blending styrene-butadiene rubber (SBR) latex and the different particle sized kaolinites. The thermal stabilities of the rubber composites were characterized using thermogravimetry, digital photography, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Kaolinite SBR composites showed much greater thermal stability when compared with that of the pure SBR. With the increase of kaolinite particle size, the pyrolysis products became much looser; the char layer and crystalline carbon content gradually decreased in the pyrolysis residues. The pyrolysis residues of the SBR composites filled with the different particle sized kaolinites showed some remarkable changes in structural characteristics. The increase of kaolinite particle size was not beneficial to form the compact and stable crystalline carbon in the pyrolysis process, and resulted in a negative influence in improving the thermal stability of kaolinite/SBR composites.     

不同硅铝比ZSM-5分子筛作为助催化剂在渣油裂化中的应用

采用不同方法表征了硅铝比(SiO2/Al2O3)为33、266和487的质子型ZSM-5分子筛,并研究了ZSM-5分子筛作为助催化剂在渣油裂解中的应用。与USY分子筛基催化剂混合后,在固定流化床上,评价了ZSM-5分子筛助催化剂的催化裂化性能。研究发现,提高ZSM-5分子筛硅铝比,可以有效抑制混合催化剂对汽油烯烃的裂解,从而避免了汽油烷烃的大量损失。加入ZSM-5助催化剂后,伴随着液化气(LPG)产率的增加,异丁烷和异戊烷产率增加,这可能是由USY基催化剂和ZSM-5助催化剂的综合效应引起的。汽油烷烃和芳烃含量的变化,引起了汽油辛烷值的增加。高硅铝比ZSM-5分子筛(硅铝比为266和487)不仅可以显著改善汽油的辛烷值,而且有效避免了汽油的大量损失。催化汽油辛烷值的改善主要是由于高硅铝比ZSM-5分子筛具有适宜的芳构化和异构化活性,这些变化主要源于高硅铝比ZSM-5分子筛小的孔道直径和适宜的酸性。     

Catalytic Pyrolysis of Biodiesel Surrogate over HZSM-5 Zeolite Catalyst

To obtain insight into the catalytic reaction mechanism of biodiesels over ZSM-5 zeolites, the pyrolysis and catalytic pyrolysis of methyl butanoate, a biodiesel surrogate, with H-type ZSM-5 (HZSM-5) were performed in a flow reactor under atmospheric pressure. The pyrolysis products were identified and quantified using gas chromatography-mass spectrometry (GC-MS). Kinetic modelling and experimental results revealed that H-atom abstraction in the gas phase was the primary pathway for methyl butanoate decomposition during pyrolysis, but dissociating to ketene and methanol over HZSM-5 was the primary pathway for methyl butanoate consumption during catalytic pyrolysis. The initial decomposition temperature of methyl butanoate was reduced by approximately 300 K over HZSM-5 compared to that for the uncatalyzed reaction. In addition, the apparent activation energies of methyl butanoate under catalytic pyrolysis and homogeneous pyrolysis conditions were obtained using the Arrhenius equation. The significantly reduced apparent activation energy confirmed the catalytic performance of HZSM-5 for methyl butanoate pyrolysis. The activation temperature may also affect some catalytic properties of HZSM-5. Overall, this study can be used to guide subsequent catalytic combustion for practical biodiesel fuels.