丁苯嵌段共聚物的加氢及性能研究

采用镍系催化剂用于丁苯嵌段共聚物 (SBS)加氢反应 ,考察了反应温度、压力、催化剂用量等对加氢反应的影响 ,得到较佳的加氢反应工艺条件 :加氢反应温度 5 5～ 6 5℃ ,反应压力大于 2 .5MPa,催化剂用量为 0 .0 5～ 0 .1g/10 0 g聚合物。该催化剂选择性好 ,可使聚合物中的共轭二烯烃段有效加氢 ,其加氢度 >98% ,苯环加氢度 <5 %。同时对加氢前后聚合物微观结构、物性变化及老化性能进行了研究。     

二氯二茂钛用于丁苯嵌段共聚物加氢的研究

选用二氯二茂钛作为丁苯嵌段共聚物加氢催化剂,用活性胶分别进行了催化剂用量、压力、温度、第三组分添加剂等对加氢效果的影响研究,得到了较好的加氢条件.用二氯二茂钛作加氢催化剂、催化剂用量为(0.2～0.4)mmol/100g聚合物时,二烯烃段加氢度大于98%,苯环加氢度小于2%.同时开展了加氢反应动力学研究,确定了加氢反应的级数及活化能.     

环戊二烯加氢制环戊烯的工艺条件优化研究

以环戊二烯为原料,使用PdCl3为催化剂,甲苯为溶剂,采用间歇式高压反应釜,常温条件加氢制备环戊烯。采用正交实验对环戊二烯加氢过程进行研究,确定了反应温度、催化剂用量、压力、反应时间等因素对加氢过程的影响。优化工艺条件为:反应温度25℃,催化剂比例1.0%(m/m),压力1.5 MPa,反应时间4 h,此时环戊烯的收率达85.5%。     

负载型Ni-Cr-B非晶态合金催化对氯硝基苯加氢制备对氯苯胺

提出一种以负载型Ni-Cr-B非晶态合金催化对氯硝基苯加氢制备对氯苯胺的工艺。通过正交实验考察反应温度、反应时间、反应压力和催化剂用量对对氯苯胺收率的影响。最优工艺条件为:反应温度60℃,反应时间4 h,反应压力1.2 MPa,催化剂用量占对氯硝基苯质量的8%。在此优化条件下,催化剂重复使用4次,对氯硝基苯转化率为99.9%,对氯苯胺选择性为99.9%,对氯苯胺平均收率为99.8%。     

Raney-Ni催化加氢合成2,3,5-三甲基氢醌的研究

以Raney-Ni为催化剂在乙酸丁酯溶剂中,间歇催化2,3,5-三甲基苯醌(TMBQ)加氢合成2,3,5-三甲基氢醌(TMHQ)。通过正交实验考察了催化剂用量、溶剂用量、温度及压力等对反应的影响。结果表明,较优反应条件为:TMBQ初始浓度为0.1 g/mL,催化剂量为TMBQ的10%,氢气压力0.7～0.8 MPa,温度为100℃(转速800 r/min)。TMHQ加氢收率可达97.3%。溶剂通过水蒸气蒸馏回收,总收率93.1%。     

高冲击强度聚苯乙烯加氢反应的研究

在氢气压力为4MPa的条件下,以环己烷为溶剂,采用环烷酸镍和三异丁基铝制备的齐格勒-纳塔型催化剂,对高冲击强度聚苯乙烯(HIPS)进行均相选择性氢化反应。研究了溶剂用量、催化剂用量、反应温度及反应时间等对HIPS加氢度的影响。结果表明:在温度60℃,Al/Ni=5且Ni用量为0.3g/100gHIPS,反应进行3h时,HIPS的加氢度为100%;加氢后HIPS的拉伸性能和弯曲性能得到大幅度提高,但冲击性能明显下降,热稳定性能基本不变。     

SRNA-4非晶态合金催化双环戊二烯液相加氢反应研究

采用SRNA-4非晶态合金催化剂对双环戊二烯(DCPD)进行了加氢反应考察,研究了搅拌速度、温度、压力和催化剂浓度各条件对双环戊二烯加氢反应的影响.结果表明DCPD加氢反应为连串反应,中间产物主要为9,10-二氢双环戊二烯(9,10-DHDCPD)和少量1,2-二氢双环戊二烯(1,2-DHDCPD);DCPD易于加氢生成中间产物9,10-DHDCPD,其继续加氢为四氢双环戊二烯(endo-THDCPD)需要较为剧烈的条件.DCPD加氢过程选用两段法,第一段为温度110℃,第二段为130℃,压力均为1.5MPa,催化剂浓度1.18%.非晶态合金(催化剂)对DCPD的加氢反应活性明显高于Raney Ni,可进行1、2位加氢反应生成1,2-DHDCPD,并且催化剂用量少,反应温度和反应压力低,反应时间短,生成副产物少.     

负载型Ru/Al_2O_3催化剂催化加氢制备氢化双酚A研究

采用负载型Ru/Al_2O_3催化剂对双酚A(BPA)加氢制备氢化双酚A(HBPA)进行了研究,考察了催化剂煅烧温度、煅烧时间、还原温度、还原时间、催化剂负载量等制备条件对反应的影响,确定催化剂最佳制备条件为:煅烧温度200℃、煅烧时间5 h、还原温度100℃、还原时间1 h,Ru负载量(w)3%。同时考察了溶剂类型、催化剂用量、反应温度、反应压力等条件对催化加氢反应的影响,确定催化加氢反应的最佳工艺条件为:溶剂选用异丙醇、催化剂用量3%、反应温度160℃、反应压力4.5MPa、反应时间4 h。在上述最佳条件下,双酚A的转化率为100%,氢化双酚A的选择性为97.08%。     

棉籽油催化加氢条件选择

本文介绍了精棉油催化加氢的试验结果。研究了反应温度、反应压力及催化剂用量对氢化反应的影响。试验表明KE—NF—20催化剂用于棉籽油加氢,是一种活性和选择性好的催化剂。在反应温度为220～240℃,反应压力O.8～1.0Mpa,催化剂用量0.2～0.3%条件下,短时间内可完成极度氢化的反应,氢化油碘值降于2mg/g以下。     

吲哚低压加氢合成吲哚啉的研究

在低压加氢反应釜中,投入Ni/γ-Al2 O3加氢催化剂,在温和的反应温度和压力下,完成了吲哚加氢合成吲哚啉的实验研究.在实验过程中考察了反应温度、加氢压力、催化剂用量和反应时间对吲哚转化率、吲哚啉选择性的影响规律.实验结果表明,温度是影响加氢反应的主要因素,在催化剂用量为5％(与吲哚质量比)、压力2.0 MPa、反应...     

贮氢合金催化丁腈橡胶加氢动力学及加氢机理

详细研究了空气气氛下、30～60℃、 THF溶液中贮氢合金催化丁腈橡胶双键加氢的宏观动力学.通过一系列不同反应温度下的实验结果获得了贮氢合金催化丁腈橡胶加氢反应的表观活化能(48.74 kJ&#8226;mol^-1),较低的表观活化能表明在贮氢合金催化丁腈橡胶溶液加氢反应中,反应物较易活化且反应具有较低的温度敏感性.利用IR和¹HNMR研究了贮氢合金催化丁腈橡胶双键加氢的选择性,结果表明1,4-BD单元较1,2-BD单元优先加氢,同时给出了trans-1,4-BD和1,2-BD加氢的动力学研究结果.根据动力学及其他研究结果提出了可能的反应机理,该机理较好地解释了反应中出现的现象.     

Continuous process for production of hydrogenated nitrile butadiene rubber using a Kenics® KMX static mixer reactor

A continuous process for hydrogenating nitrile butadiene rubber (NBR) was developed and its performance was experimentally investigated. A Kenics® KMX static mixer (SM) is used in the process as a gas–liquid reactor in which gaseous hydrogen reacts with NBR in an organic solution catalyzed by an organometallic complex such as an osmium complex catalyst. The Kenics® KMX SM was designed with 24 mixing elements with 3.81 cm diameter and arranged such that the angle between two neighboring elements is 90°. The internal structure of each element is open blade with the blades being convexly curved. The dimensions of the SM reactor are: 3.81 cm ID 80 S and 123 cm length and was operated cocurrently with vertical upflow. The NBR solutions of different concentrations (0.418 and 0.837 mol/L with respect to [C?C]) were hydrogenated by using different concentrations of the osmium catalyst solution at various residence times. The reactions were conducted at a constant temperature of 138°C and at a constant pressure of 3.5 MPa. From the experimental results, it is observed that a conversion and/or degree of hydrogenation above 95% was achieved in a single pass from the designed continuous process. This is the first continuous process for HNBR production that gives conversions above 95% till date. Optimum catalyst concentration for a given mean residence time to achieve conversions above 95% were obtained. Finally, a mechanistic model for the SM reactor performance with respect to hydrogenation of NBR was proposed and validated with the obtained experimental results. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Catalytic hydrogenation of nitrile rubber using palladium and ruthenium complexes

The catalytic hydrogenation of acrylonitrile‐butadiene copolymer (nitrile rubber, NBR) using Pd(OAc)₂ or RuCl₂(PPh₃)₃ catalysts has been investigated in order to produce a totally saturated nitrile rubber. The hydrogenation of NBR is effective with both catalysts and achieved total conversion under the appropriate reaction conditions. In the case of palladium the effects of reaction parameters such as reaction temperature, pressure, time, catalyst concentration, and NBR concentration have been investigated. Even though both ruthenium‐ and palladium‐based catalysts are effective in the production of HNBR, the former requires harsh reaction conditions and has the drawback of gel formation under high conversion, motivating the migration to RuCl₂ (PPh₃)₃ as an alternative catalyst. The degree of hydrogenation was determined by IR and NMR spectroscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

New method for hydrogenating NBR latex

A new hydrogenation system consisting of hydrazine hydrate and sodium periodate has been developed for hydrogenation of nitrile‐butadiene rubber (NBR) latex by diimide reduction technique. The optimization of the reaction conditions was obtained. The influences of the concentration of reactants, reaction time, and temperature on hydrogenation degree were investigated. The results indicated that hydrogenation degree of the product (HNBR) can be extended to 95% through this new method. In addition, ¹H‐NMR and infrared spectra confirmed that C?C double bonds in NBR were successfully hydrogenated without reduction of the CN group. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

贮氢合金催化丁腈橡胶溶液加氢反应工艺条件的研究

研究了各种反应条件对贮氢合金MINi5-x（CoMnAl）x的氢化物对丁腈橡胶溶液双键加氢的影响。随着反应温度升高氢化度也提高；当舍金氢化物超过理论用量的2倍时，氢化度与催化剂的用量无关；氢化度与反应时间不是简单的线性关系；关于溶剂的影响，发现溶剂为氯仿时无加氢反应发生，而在四氢呋喃中则可得到具有较高氢化度的产物。此外还发现丁腈橡胶氢化度受反应气氛、氢压等因素的影响。     

贮氢合金催化共轭二烯烃类聚合物双键加氢的研究

研究了共轭二烯烃类聚合物在贮氢合金氢化物存在下双键加氢的情况。结果表明AB；型贮氢合金[包括LaNi5和MINi5-x(CoMnAl)8]可催化NBR、NR、BR、SBS等共轭二烯烃聚合物双键加氢，其氢化度分别可达33．5％、31．1％、45．8％、32．3％。采用IR、^1H NMR、碘量分析法等手段对加氢产物进行了分析，表明聚合物中双键加氢的同时，NBR中的-C≡N和SBS中的苯环不受影响。此外。研究结果还表明合金组成、表面处理方式等对贮氢合金催化共轭二烯烃类聚合物双键加氢活性有影响。合金氢化物在共轭二烯烃类聚合物双键加氢过程中具有提供氢源与催化双重功能。     

新型固定床Raney镍(Ⅱ)成型合金的浸取过程

以20%的拟薄水铝石为黏结剂制备新型固定床Raney镍催化剂,采用苯加氢为模型反应,研究了前驱物成型合金浸取条件对催化剂加氢活性的影响.实验结果表明,对于860℃焙烧2 h后的成型合金,以10%～20%的NaOH溶液在80～90℃浸取3～4 h可得到具有较高加氢活性的固定床Raney镍催化剂.浸取反应可在1～4 h内基本完成,浸取后催化剂表面出现微孔结构,具有较好的苯加氢活性和活性稳定性,可在120℃、0.5 MPa、空速2 h^-1的缓和条件下实现苯的完全转化.     

影响偶氨法常压氢化丁苯胶乳氢化度及凝胶的因素

研究了采用水合肼（N2H2·H2O）/H2O2/CuSO4使冷法聚合丁苯胶乳在常压下氢化的各种条件,包括乳化剂种类及用量、催化剂CuSO4的用量、N2H4·H2O及H2O2的用量、反应温度及反应时间等对氢化丁苯橡胶氢化度及凝胶含量的影响。结果表明,当加入质量分数为0 8％的十二烷基苯磺酸钠乳化剂,CuSO4催化剂用量为0.0025 mmol/g,反应温度为55℃,反应时间为7h,N2H4/C=C之摩尔比为1.8,H2O2/N2H4之摩尔比为1.5时,可得到氢化度为98％。凝胶质量分数小于0.6％的氢化丁苯橡胶。     

Continuous slurry hydrogenation of soybean oil with copper-chromite catalyst at high pressure

Selective hydrogenation of soybean oil to reduce linolenic acid is accomplished better with copper than with nickel catalysts. However, the low activity of copper catalysts at low pressure and the high cost of batch equipment for high-pressure hydrogenation has precluded their commercial use so far. To evaluate continuous systems as an alternative, soybean oil was hydrogenated in a 120 ft × 1/8 in. tubular reactor with copper catalyst. A series of hydrogenations were performed according to a statistical design by varying processing conditions: oil flow (0.5 L/hr, 1.0 L/hr and 2.0 L/hr), reaction temperature (180 C and 200 C), hydrogen pressure (1,100 psig and 4,500 psig) and catalyst concentration (0.5% and 1.0%). An iodine value (IV) drop of 8–43 units was observed in the products whereas selectivity varied between 7 and 9. Isomerization was comparable to that observed with a batch reactor. Analysis of variance for isomerization indicated interaction between catalyst concentration and hydrogen pressure and between catalyst concentration and temperature. The influence of pressure on linolenate selectivity was different for different temperatures and pressure. Hydrogenation rate was significantly affected by pressure, temperature and catalyst concentration.     

Pt-Cu-Zn/C催化加氢制备DSD酸工艺

本文研究了4,4'-二硝基二苯乙烯-2,2'-二磺酸(DNS酸),在Pt/C催化剂存在下,Zn和Cu为抑制剂,水相体系中液相催化加氢制备DSD酸。Pt-Cu-Zn/C催化剂制备DSD酸具有很好的活性和选择性,能有效抑制苄基物及影响色度的杂质的生成。较佳的工艺条件为:DNS酸钠盐质量浓度为12~20%、Pt/C催化剂量为硝基物的0.5~0.7%,反应温度40~60℃、pH4~6、氢气压力1.0 MPa。DNS酸转化率100%,DSD酸选择性98.5%以上,收率98%,DSD酸含量均达到95%以上(氨基值法),苄基物含量低于0.1%(外标法),色度低于0.2。新工艺生产每吨DSD酸产生废水12吨,废水COD值为24 mg/L,无色透明。