铝系催化剂催化合成聚酯的性能研究

以5种含铝化合物为催化剂,采用对苯二甲酸二甲酯（DMT）路线合成聚酯,对聚合产物进行特性黏度、色值和DSC分析。结果表明：5种铝系催化剂的催化活性均低于常规催化剂,其中,铝酸钠的催化活性最高;铝系催化剂所得的聚酯的色相b值高于Sb2O3催化的聚酯的b值,但低于钛酸正丁酯催化的聚酯的b值;铝酸钠和硅酸钠复合后作为催化剂,不改变PET切片的等温结晶规律,且催化所得聚酯的结晶青色力比常规Sb2O3催化的聚酯略有提高;选择溶解性好的含铝化合物和减少催化剂用量对增加催化活性和改善聚酯色相有利。     

专利摘登

<正>聚酯聚合催化剂、聚酯制造以及中空制品、纤维和薄膜用聚酯使用这种高催化剂活性催化剂制得的聚酯具有良好的色泽,热稳定性好等特点。这种催化剂中含有铝化合物和磷化合物,用它制造的聚酯,可以生产中空制品、纤维和薄膜等。例如:将TPA和EG进行酯化,先制得低聚物的混合物,然后,在由碱式乙酸铝,苯甲基膦酸二乙酯和3,5-二叔丁基-4-羟基苯甲膦酸二乙酯制得的催化剂存在下,将低聚物的混合     

稀土元素化合物在聚酯聚合工艺中的催化作用

以不同的稀土金属元素化合物及稀土化合物/三氧化二锑复合物分别用作聚酯酯交换和缩聚催化剂,对各工艺参数进行分析,并对产品性能进行测试与表征.结果表明:稀土化合物可作为聚酯酯交换的催化剂和缩聚助催化剂;使用稀土化合物/三氧化二锑复合催化剂,能有效提高酯交换效率,缩短反应时间,降低酯交换开始温度,所得聚酯产品的色相优于普通三氧化二锑催化所得聚酯,结晶度比普通三氧化二锑催化所得聚酯的高,且重稀土有机化合物比轻稀土无机化合物催化效率更高.     

用铝硅复合催化剂催化聚合的聚酯性能研究

以三氧化二锑(Sb2O3)、不同质量比的铝酸钠/硅酸钠复合物分别作为聚酯缩聚催化剂制取聚酯切片,利用凝胶渗透色谱(GPC)、色值、差示扫描量热(DSC)及热失重(TG)对聚合产物分别进行分析.结果表明:以铝硅复合催化剂F1[n(铝酸钠)∶m(硅酸纳)=4∶1]催化制取的聚酯相对分子质量及分子质量分布接近以Sb2O3催化制取的聚酯,而且色相指标比用Sb2O3催化制取的聚酯好,其白度L值高,黄度b值低;复合催化剂制取的聚酯的玻璃化转变温度(Tg)低于Sb2O3催化制取的聚酯,但结晶温度高于Sb2O3催化的聚酯,表明聚酯的结晶能力有所提高;复合催化剂催化聚合的聚酯热性能与常规Sb2O3催化的聚酯基本接近.     

钛系聚酯催化剂研究技术进展

对比分析了锑、锗、钛系聚酯催化剂;详细介绍了钛系聚酯催化剂的不同研究方向、技术进展以及应用情况。指出钛系聚酯催化剂的研究包括钛化合物的稳定化、钛酸酯或氯化钛的水解或共水解以及钛化合物的负载化3个方面,钛系催化剂稳定性及合成的聚酯色相明显提高。高效环保的钛系催化剂取代传统锑系催化剂将是聚酯工业发展的必然结果。     

专利摘登

聚酯制造用催化剂 本发明公开了一种聚酯制造用催化剂,它包括：由磷化合物,镁化合物和钛化合物组成的混合溶液。例如：将TPA166份和EG75份（以质量计）的混合物,在300Pa和290℃下,用质量分数为5&#215;10^-6的钛化合物,磷化合物和乙酸镁为催化剂进行聚合,即可制得特性黏度为0．66的聚酯,这种聚酯具有色调好和耐热性好的特点。     

聚酯催化剂的研究进展

详细叙述了锑系、钛系、锗系、锡系、铝系和酶催化剂在聚酯反应中的应用情况,介绍了这些催化剂的分类和它们的优、缺点,指出高效环保型催化剂是聚酯催化剂发展的方向。     

铝硅复合催化剂合成PET的性能研究

采用对苯二甲酸二甲酯(DMT)路线以铝、硅化合物为复合催化刺合成聚对笨二甲酸乙二醇酯(PET),对PET的特性粘数、色值和热性能进行了测试,与Sb2O3催化合成的PET进行了比较,结果表明:铝硅复合催化剂的催化活性低于Sb2O3催化剂,所得PET特性粘数较低;铝硅复合催化剂所得PET的b值高于Sb2O3催化所得PET的...     

专利摘登

聚酯用含羟基脂肪族羧酸的聚合催化剂及其制造将100份羟基脂肪族羧酸(如:羟基醋酸和乳酸)与1~10份的锑化物进行反应合成催化剂,用此催化剂可以制得高透明度和满意色调的聚酯。例如:将27g Sb2O3溶解于乳酸质量分数为90%的水溶液中,制得催化剂,用它去催化EG与TPA的聚合反应,即可制得上述聚酯。JP2004315734制造聚酯用的多组分催化体系这种基于锗的多组分催化体系可用做PET的缩聚反应催化剂,由它制得的PET可用于生产瓶子、纤维或薄膜。该多组分催化体系含有锗和不少于1种的催化增效剂,此增效剂可从铝、硅、铜、锰、锂等的化合物中选择,如…     

仪征化纤公司研制成功钛系聚酯催化剂

<正>钛系聚酯催化剂对人体健康及生态环境均无影响,具有较高的催化剂活性。仪征化纤公司对钛系聚酯催化剂进行了研究,并在2004年开始与国内化工单位、研究院所合作,开展钛系聚酯催化剂的专题研究工作,但由于国内新型钛系聚酯催化剂商业化过程缓慢,钛系聚酯催化剂应用研究也一直未取得突破。仪征化纤公司选择从聚酯瓶切片聚合研究入手,进一步开展钛基复合催化剂的研制,将其纳入2008年十大科技攻关项目之一。以不同钛基化合物作为聚酯催化剂进行聚合     

Direct synthesis of hydrogen peroxide from H2 and O2 using zeolite-supported Au catalysts

The direct synthesis of hydrogen peroxide from H₂ and O₂ using zeolite-supported Au catalysts is described and their activity is contrasted with silica- and alumina-supported Au catalysts. Two zeolites were investigated, ZSM-5 and zeolite Y. The effect of calcination of these catalysts is studied and it is found that for uncalcined catalysts high rates of hydrogen peroxide formation are observed, but these catalysts are unstable and lose Au during use. Consequently, reuse of these catalysts leads to lower rates of hydrogen peroxide formation. However, catalysts calcined at 400 °C are more stable and can be reused without loss of gold. The use of zeolites as a support for Au gives comparable rates of hydrogen peroxide formation to alumina-supported Au catalysts and higher rates when compared with silica-supported catalysts. prepared using a similar method. Zeolite Y-supported catalysts are more active than ZSM-5-supported catalysts for the stable calcined materials. It is considered that the overall activity of these supported catalysts may be related to the aluminium content as the activity increases with increasing aluminium content.     

Dehydration of ethyl alcohol on alumina-coated silica

Catalysts were prepared by precipitation of aluminium hydroxide on a wet silica gel. The dehydration of ethyl alcohol on catalysts varying in alumina content was studied at 307° using a flow system. The products of dehydration were ethylene, ether and water. The kinetics of the formation of ethylene followed the Langmuir-Hinshelwood mechanism, while the formation of ether occurred according to the Langmuir-Hinshelwood mechanism and the Rideal-Eley mechanism simultaneously. The catalytic activity was controlled by the amount of aluminium on the surface. The rate constants were correlated with the surface nature of the catalysts.     

Supported nickel catalyst from hydroxycarbonate of nickel and aluminium

The hydroxycarbonate of nickel and aluminium (Ni/ Al = 3) with a hydrotalcite-like structure is an outstanding precursor of the active component of supported nickel catalysts. Good mechanical strength and suitable nickel content of these catalysts, which are necessary for practical applications, can be achieved by mechanical mixing of this compound with an additional support. The catalyst prepared from a mixture of 56.5 wt-% of nickel-aluminium hydroxycarbonate and 43.5 wt-% of γ-alumina was proven to have a stable catalytic activity in the methanation reaction at 2 MPa and 800 K.     

Studies on rejuvenation of spent residue hydroprocessing catalysts by leaching of foulant metals: influence of inorganic salt additives on the leaching efficiency of organic acids

A comparative study has been made on the efficiency of oxalic, malonic and acetic acids for selective removal of metal foulants (e.g. vanadium) from spent residue hydrotreating catalysts in the presence and absence of aluminium nitrate. The influence of concentration of the added salt (aluminium nitrate) on the leaching efficiency of the three acids was also studied. The treated catalysts were characterized and the improvements in surface area, pore volume and HDS activity as a result of leaching with each reagent compared. The studies revealed that addition of aluminium nitrate enhanced the leaching efficiency of each acid to a different degree. The rate of vanadium leaching by oxalic acid was increased substantially by aluminium nitrate addition whereas for acetic acid there was only a moderate enhancement in leaching rate. The enhanced leaching by the aluminium nitrate-organic acid system may be explained in terms of a synergistic mechanism involving oxidizing and complexing reactions. The improvement in surface area and pore volume achieved on rejuvenation were related to the extent of removal of vanadium from the catalyst. The HDS activity of the catalyst was also increased significantly by leaching of the deposited metals. The selectivity for vanadium leaching (V/Mo ratio) was found to be an important factor for HDS activity recovery.     

The Current Status of Catalysis and Catalyst Development for the Industrial Process of Poly(ethylene terephthalate) Polycondensation

Abstract

In this survey of the industry, it is shown that despite the partial dissatisfaction with antimony-based polycondensation catalysts these catalysts are expected to remain the mainstay of industrial PET polycondensation catalysis. This is despite the intensive efforts invested in the search of other, stable and inexpensive non-antimony catalysts, such as those based on titanium, aluminium, and several traodtion metals such as molybdenum, cobalt and zirconium.     

The development of novel metal-based combustion catalysts

The performance of a newly developed metal-based combustion reactor is discussed. The heat transfer properties under combustion conditions of a so-called sintered-metal reactor covered with a palladium oxide on silica catalyst have been studied up to 550°C. Also enhancement of the thermal stability of the silica by means of addition of aluminium was investigated. With mixed oxides of silicon and aluminium combustion catalysts have been prepared and they have been shown to exhibit good activity in the combustion of methane.     

钛系催化剂对聚酯缩聚反应速度和热稳定性影响的研究

研究了K2TiF6、(C4H9O)4Ti、Sb2O33种催化剂的缩聚反应速度,并对3种催化剂合成的切片进行了热稳定性比较(Δ[η]、TG)。结果表明:钛系催化剂的催化活性明显高于常规Sb2O3,其中以(C4H9O)4Ti的催化活性最高;(C4H9O)4Ti的动力学曲线具有阶段性,其高催化活性体现在缩聚反应的中后期;对3种催化体系制得的PET切片进行热稳定性测试的结果表明:采用(C4H9O)4Ti作为催化剂配合稳定剂SI与Co2+可制得色相良好,热稳定性高的聚酯切片。     

亲水抗菌聚酯纤维的研究

采用精对苯二甲酸(PTA)、乙二醇(EG)与多羟基化合物共聚,制得亲水聚酯(PET)切片,将该亲水PET与银系抗菌母粒共混纺丝,制得亲水抗菌PET纤维,并对其性能进行了研究。结果表明:加入相对PTA质量分数为0.8%的多羟基化合物,亲水PET的亲水性能较好,表面接触角为53.5°,特性黏数为0.591dL/g;亲水抗菌PET纺丝温度比常规PET切片低15～20℃;添加银系抗菌剂质量分数为10%的亲水抗菌PET纤维有较佳的抗菌性能,对金黄色葡萄球菌和大肠杆菌的抗菌率均大于99%,抗菌活性值均大于2,断裂强度为2.6 cN/dtex,回潮率约0.8%。