以单体酸为原料制备生物柴油

研究了以单体酸为原料制备生物柴油的方法,反应以对甲苯磺酸为催化剂,单体酸与甲醇进行酯化反应获得脂肪酸甲酯。分别考察了酯化反应条件如甲醇与脂肪酸的摩尔比、反应时间、催化剂浓度以及反应温度对酯化率的影响。通过正交实验得到最佳酯化反应参数：醇酸摩尔比3∶1,反应时间3 h,对甲苯磺酸用量6%,反应温度60 ℃,该条件下单体酸酯化率达98.25%。实验制得的单体酸甲酯生物柴油的主要性能指标符合ASTM质量标准,并与0^#柴油性质接近。     

Cu负载型催化剂用于乙醇氨化合成乙腈

研究了不同载体SAPO-11、Montmorillonite-K10、γ-Al₂O₃、ZnO和MgO负载Cu的催化剂对乙醇氨化合成乙腈反应的影响。结果表明,经还原的Cu起脱氢作用,载体不仅起分散作用而且具有协同催化的作用,其酸碱性对催化结果有显著影响,其中Cu/γ-Al₂O₃负载型催化剂具有比较理想的催化效果。在此研究基础上,考察了反应条件对Cu/γ-Al₂O₃催化剂催化性能的影响,筛选出乙醇氨化合成乙腈的适宜反应条件：反应温度290℃、反应压力0.1 MPa、乙醇重时空速1.0 h^－1、氨醇摩尔比7.0,在该条件下乙醇转化率99.7%,乙腈选择性达到92.6%。     

高效稳定的铜镍催化剂在草酸二甲酯加氢中的应用

为了探索高效、稳定的草酸二甲酯（DMO）加氢制乙醇酸甲酯（MG）催化剂,采用水热合成法制备Cu-Ni/SiO₂催化剂,探索了不同Cu：Ni摩尔比对于催化剂活性的影响。通过XRD、TEM和XPS等表征,结果表明：利用二氧化硅微球作载体,铜镍物种的分散更加均匀。并且调变不同的Cu：Ni摩尔比,对Cu⁺在催化剂中的比例有一定的影响,从而影响乙醇酸甲酯的收率。在氢酯比为150、反应压力2 MPa、反应温度200℃和液时空速为0.5 h^-1的反应条件下,Cu：Ni摩尔比为1：1时的催化剂Cu₁Ni₁/SiO₂表现出了最好的催化性能,草酸二甲酯的转化率达到90%,乙醇酸甲酯的选择性达到了80%,催化剂能稳定运行100 h。上述结果可为研制催化活性高、选择性强、寿命长、易于生产乙醇酸甲酯的催化剂提供一定的参考。     

Ce-Mo-Ti-V催化制备苯四甲酸二酐

开发了一种由均四甲苯空气气相氧化制均苯四甲酸二酐过程所需的催化剂,该催化剂活性组分为Ce-Mo-Ti-V。通过实验研究了载体种类、活性组分、温度、空速和反应物浓度对工艺结果的影响。实验表明：在空速6 000 h^－1,温度为455℃,均四甲苯浓度为20 g/m³时,均苯四甲酸二酐的质量收率达到101.7%。     

SO4^2-/TiO2-Al2O3催化合成双季戊四醇六脂肪酸酯

以自制SO₄^2-/TiO₂-Al₂O₃固体超强酸为催化剂,进行双季戊四醇和脂肪酸的酯化反应,合成了双季戊四醇六脂肪酸酯,考察了酸醇摩尔比、催化剂用量、反应温度、反应时间等条件对酯化反应的影响。确定了较优的合成条件：n(脂肪酸)﹕n(双季戊四醇)=6.5﹕1,催化剂用量为总反应物质量的0.060%,210 ℃回流反应6 h。用红外光谱对反应产物进行了表征,结果表明,SO₄^2－/TiO₂-Al₂O₃固体超强酸在双季戊四醇六脂肪酸酯合成反应中有较高的催化活性和高的反应选择性,酯化率达98%以上,且催化剂重复使用8次仍保持较高活性。双季戊四醇六脂肪酸酯产品结构经FTIR表征确认。     

乙醇酸甲酯水解制备乙醇酸工艺

在固定床反应器内,对乙醇酸甲酯催化水解制备乙醇酸工艺进行研究,考察了反应温度、水酯物质的量比和空速对乙醇酸甲酯转化率的影响。结果表明,优化的水解工艺条件为质量空速(1~3)h-1,反应温度(70~85)℃,水酯物质的量比5~10。年产1 000 t合成气制乙醇酸中试试验结果表明,采用反应精馏进行乙醇酸甲酯水解,在回流比0.5~6.0条件下,乙醇酸甲酯水解转化率接近100%,乙醇酸水溶液产品质量达到企业标准要求。     

壳聚糖硫酸盐催化合成衣康酸二甲酯

以壳聚糖和硫酸为原料,制备了壳聚糖硫酸盐,利用红外及元素分析对壳聚糖硫酸盐进行了结构表征。将其用于催化衣康酸与甲醇合成衣康酸二甲酯的反应,考察了酸醇比、时间、催化剂用量、温度等条件对衣康酸二甲酯收率的影响,得到的最佳工艺条件为：壳聚糖硫酸盐用量占反应物料总质量的2%,n(甲醇)∶n(衣康酸)=7∶1,反应温度为140 ℃,反应时间6 h,在此条件下,产品收率为86.6%。衣康酸二甲酯经气质定性分析,气相色谱检测纯度大于98%。催化剂经简单干燥处理,循环使用5次后产品收率为84.0%。     

乙醇酸甲酯催化加氢制备乙二醇

在微型固定床反应器上,以乙醇酸甲酯为原料,使用Cu-Cr催化剂,催化加氢制备了乙二醇.考察了氢酯摩尔比、反应温度、反应压力、床层空速对反应的影响,并对加氢催化剂的活性进行了XRD的评价.结果显示最佳反应条件为:氢酯摩尔比40:1、反应温度210℃、反应压力3.5MPa,床层空速0.4h-1时,乙醇酸甲酯的转化率达94%...     

精细化工与催化 阳离子交换树脂改性及其在乙醇酸甲酯水解制备乙醇酸反应中的应用

采用AlCl₃和SnCl₄对苯乙烯系强酸性阳离子交换树脂进行改性,考察树脂改性条件对乙醇酸甲酯水解制备乙醇酸反应的影响,并优化水解工艺条件。结果表明,最佳树脂改性条件为:采用AlCl₃-SnCl₄等物质的量混合物联合改性,其添加量为树脂质量的8%~10%,改性水浴温度(70~75) ℃,改性时间(8~10) h;优化的乙醇酸甲酯水解制备乙醇酸的工艺条件为:空速(3~6) h^-1,水解温度(75~85) ℃,去离子水与乙醇酸甲酯物质的量比(10~20)∶1。经过300 h的稳定性实验表明,树脂改性后稳定性良好。     

CO2+离子交换NaX分子筛催化苯乙烯环氧化

将5次固态交换制备的Co²⁺-NaX于500 ℃焙烧6 h,再进行一次固态交换制备高稳定性催化剂,ICP分析表明其Co²⁺含量为9.13%,高于5次固态交换Co²⁺-NaX的平衡Co²⁺含量（8.42%）。采用XRD、N₂吸附-脱附对催化剂进行表征,结果表明,分子筛离子交换后其骨架结构没有受到破坏,然而随交换进入分子筛Co²⁺含量增多,其有序性下降越明显。通过正交实验对该催化剂催化苯乙烯环氧化进行考察,确定了优化的反应条件：苯乙烯用量6 mL,催化剂1.0 g,溶剂48 mL,反应温度80 ℃,反应时间6 h。在此条件下,环氧苯乙烷平均收率为39.5%。采用该法制备催化剂其活性能够进一步提高,且重复使用活性保持不变。     

Catalytic oxidation of NO over Ce-doped Mn/TiO2

Mn-Ce/TiO₂ catalyst was prepared by impregnating Mn-Ce on TiO₂ and was characterized by XRD,BET and PL. The influences of Ce-doping concentration,loading,calcinations temperature,space velocity,inlet concentration of NO and volume fraction of oxygen on the performance of catalytic oxidation were examined. The results showed that the effect of doping Ce not only increased the surface area of MnO_x/TiO₂ but also enhanced the dispersion of active phase over TiO₂. At Ce-doping concentration of [Ce]/[Mn]=1/3,10% loading Mn-Ce/TiO₂ catalyst calcined at 300 ℃ for 3 h had high catalytic oxidation activity. When inlet concentration of NO was 300 μL/L,O₂ 10%,space velocity was 41000 h^－1,oxidation rate of NO over Mn-Ce/TiO₂ reached 58% at 200 ℃.     

AgBr/Zn3(OH)2V2O7·2H2O可见光催化降解亚甲基蓝溶液

采用水热和沉淀两步合成法制备AgBr/Zn₃(OH)₂V₂O₇·2H₂O催化剂,研究其在可见光下降解亚甲基蓝溶液的性能,并考察催化剂用量、亚甲基蓝溶液初始浓度、pH值以及盐浓度对光催化性能的影响,评价AgBr/Zn₃(OH)₂V₂O₇·2H₂O催化剂的重复使用性能。结果表明,在前驱液pH为10、120 ℃水热10 h、Ag与Br物质的量比为0.20条件下制备的复合催化剂在可见光下反应120 min后,1.0 g·L^-1的催化剂对10 mg·L^-1的亚甲基蓝溶液脱色率达到85.2%。NaCl对亚甲基蓝的降解起抑制作用,Na₂SO₄对亚甲基蓝的降解起促进作用。催化剂重复使用4次后,光照120 min后的亚甲基蓝溶液脱色率可达66.4%。催化剂对不同初始浓度亚甲基蓝溶液的光催化降解符合一级动力学模型。     

Membrane enhanced COD degradation of pulp wastewater using Cu2O/H2O2 heterogeneous Fenton process

Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction, in particular, with no limitation for the working pH and no production of the sludge. In this work, a combination of catalyst Cu₂O and pore-channel-dispersed H₂O₂ is proposed to treat the pulp wastewater. Degradation degree of CODs in the wastewater was up to 77% in the ceramic membrane reactor using Cu₂O powder (2.0 g·L^-1) and membranefeeding H₂O₂ (0.8 ml·L^-1) within 60 min. Evolution of ·OH radical formation in the advanced oxidation process was analyzed with a fluorescent method. Utilization efficiency of H₂O₂ was successfully enhanced by 10% with the membrane distributor. Further on, the catalyst recyclability was evaluated in a five-cycle test. The concentration of copper ions being dissolved in the treated water was monitored with ICP. After Cu₂O/H₂O₂ (membrane) treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^-1 with regard to the national standard GB25467-2010.     

负载型钴锰复合金属氧化物催化剂催化分解N_2O

以ZrO_2为载体,采用浸渍法制备负载型钴锰复合金属氧化物催化剂,研究催化剂活性组分负载量、Co与Mn物质的量比、焙烧条件及含H_2O气氛对N_2O转化率的影响。结果表明,催化剂最佳制备条件为:活性组分Co负载质量分数3%,Co与Mn物质的量比为1∶1,焙烧升温速率2℃·min-1,焙烧温度900℃。该条件制备的负载型钴锰复合金属氧化物催化剂在反应温度850℃时,N_2O转化率达98.7%。当反应气氛中H_2O体积分数小于20%条件下,850℃时N_2O转化率高于90%,表明催化剂具有较强的抗水性能。     

一种硼氢化钠水解制氢的技术路线

硼氢化钠催化水解制氢是一项实用、环保、可行的制氢技术。直接应用固态的硼氢化钠或与催化剂的混合物制氢比使用其溶液制氢更便捷、安全。本文设计了小型制氢反应器,使用NaBH₄和乙酸钴粉末的混合物作初始反应物。研究了初始反应温度、供水速率和NaBH₄与乙酸钴的混合比对产氢特性的影响。实验结果表明,反应区外围使用冷却水时,可将反应温度波动控制在6～8 ℃,这有利于降低氢气流速的峰值和保持相对稳定的氢气流。当催化剂的混合量大于4%时,氢气的转化率可达95%以上。     

Combined effect of H2O and SO2 on V2O5/AC catalysts for NO reduction with ammonia at lower temperatures

Combined effect of H₂O and SO₂ on V₂O₅/AC the activity of catalyst for selective catalytic reduction (SCR) of NO with NH₃ at lower temperatures was studied. In the absence of SO₂, H₂O inhibits the catalytic activity, which may be attributed to competitive adsorption of H₂O and reactants (NO and/or NH₃). Although SO₂ promotes the SCR activity of the V₂O₅/AC catalyst in the absence of H₂O, it speeds the deactivation of the catalyst in the presence of H₂O. The dual effect of SO₂ is attributed to the SO₄²⁻ formed on the catalyst surface, which stays as ammonium-sulfate salts on the catalyst surface. In the absence of H₂O, a small amount of ammonium-sulfate salts deposits on the surface of the catalyst, which promote the SCR activity; in the presence of H₂O, however, the deposition rate of ammonium-sulfate salts is much greater, which results in blocking of the catalyst pores and deactivates the catalyst. Decreasing V₂O₅ loading decreases the deactivation rate of the catalyst. The catalyst can be used stably at a space velocity of 9000 h⁻¹ and temperature of 250 °C.     

一种新型炭载体在乙炔氢氯化反应中的应用

采用等体积浸渍法制备了一系列不同载体的HgCl₂催化剂,利用BET、原子荧光光谱仪（AFS）、元素分析仪（EA）等对样品进行了表征,考察了催化剂在固定床反应装置上进行乙炔氢氯化反应的性能,同时对催化剂失活原因进行了初探。结果表明,不同载体催化剂催化性能和失活原因差异很大,其中以AC-2（沥青基球形炭）为载体的HgCl₂/AC-2催化性能最佳,当HgCl₂含量为5%（质量分数）、乙炔空速36 h^－1、温度140 ℃、n(HCl)∶n(C₂H₂)=1.05～1.1时,其初始转化率>99%（比HgCl₂/AC-1提高39%）,选择性接近100%,寿命可达3168 h,催化性能优于现有工业高汞催化剂。     

Kinetics of CO and H2 oxidation over CuO-CeO2 catalyst in H2 mixtures with CO2 and H2O

The kinetics of CO and H₂ oxidation over a CuO-CeO₂ catalyst were simultaneously investigated under reaction conditions of preferential CO oxidation (PROX) in hydrogen-rich mixtures with CO₂ and H₂O. An integral packed-bed tubular reactor was used to produce kinetic data for power-law kinetics for both CO and H₂ oxidations. The experimental results showed that the CO oxidation rate was essentially independent of H₂ and O₂ concentrations, while the H₂ oxidation rate was practically independent of CO and O₂ concentrations. In the CO oxidation, the reaction orders were 0.91, −0.37 and −0.62 with respect to the partial pressure of CO, CO₂ and H₂O, respectively. In the H₂ oxidation, the orders were 1.0, −0.48 and −0.69 with respect to the partial pressure of H₂, CO₂ and H₂O, respectively. The activation energies of the CO oxidation and the H₂ oxidation were 94.4 and 142 kJ/mol, respectively. The rate expressions of both oxidations were able to predict the performance of the PROX reactor with accuracy. The independence between the CO and the H₂ oxidation suggested different sites for CO and H₂ adsorption on the CuO-CeO₂ catalyst. Based on the results, we proposed a new reaction model for the preferential CO oxidation. The model assumes that CO adsorbs selectively on the Cu⁺ sites; H₂ dissociates and adsorbs on the Cu⁰ sites; the adsorbed species migrates to the interface between the copper components and the ceria support, and reacts there with the oxygen supplied by the ceria support; and the oxygen deficiency on the support is replenished by the oxygen in the reaction mixture.