共查询到20条相似文献,搜索用时 109 毫秒
1.
2.
下一代石油化工催化剂的开发热点(1)由甲烷直接合成甲醇和甲醛由甲烷氧化直接合成甲醇和甲醛已经进行了70多年的研究,由于甲醇和甲醛的反应活性远高于甲烷,氧化反应极易导致生成二氧化碳和水,至今这一研究尚未取得重大突破。有人估算,如果甲醇或甲醛的单程收率达... 相似文献
3.
4.
强化传热在氧化器上的应用周乃石(衢州化学工业公司设计院浙江省324004)精甲醇与净制的空气、蒸汽配成比例的三元混合气体,通过一系列的预处理后进人氧化器,在银触层的存在下,发生氧化脱氢反应生成甲醛气体。甲醇的氧化反应是强放热反应,所生成的甲醛反应气体... 相似文献
5.
由甲醇生产甲醛和醋酸工艺进展 总被引:1,自引:1,他引:0
在甲醇的诸多下游产品中 ,甲醛 (HCHO)最重要 ,其次是醋酸 (CH3 COOH)。它们不但是最终产品 ,而且是生产其它众多化学品的中间体。世界甲醛的年产量约为2 0 0 0万t ,醋酸的年产量约为 6 0 0万t。本文论述甲醇转化为甲醛和醋酸的工艺进展。1 甲醛工艺甲醛通常由甲醇和空气经过汽相催化部分氧化制取 ,有 2种基本类型的甲醛生产工艺 ,其区别是甲醇 /空气平衡的化学计量比和使用的催化剂不同。氧化脱氢是一种老工艺 ,它使用银基催化剂 ,而且甲醇的化学计量值过量以防止过度氧化 (生成二氧化碳 )。产品溶液中所含的剩余甲醇必须经过精馏脱除… 相似文献
6.
Herzog Stefanie 《精细化工原料及中间体》2014,(8)
正本发明涉及到从甲醇和醋酸生产丙烯酸的过程,其中在反应区A,甲醇在非均相催化剂气相反应中部分氧化成甲醛,由此得到的产品气体混合物A和醋酸源用于制备含有醋酸和甲醛,并且醋酸相对甲醛过量的反应气体输入混合物B;在反应区B,反应气体混合物B中的甲醛和醋酸,在非均相催化剂下进行羟醛缩合反应生成丙烯酸,未反应醋酸与丙烯酸目标产物一起存在于产品气体混合物B中, 相似文献
7.
《精细化工原料及中间体》2016,(11)
正由甲醇合成聚甲醛二甲醚的工艺方法本发明涉及合成聚甲醛二甲醚的工艺方法,解决聚甲醛二甲醚合成成本高收率低的问题,采用由甲醇合成聚甲醛二甲醚的工艺方法,该工艺分为反应区和分离区;反应区包括甲醇储槽、预热器、固定床反应器和鼓泡反应器;反应区工艺步骤为甲醇经预热汽化与空气混合后进入固定床反应器,经甲醛合成催化剂催化氧化生成甲醛,进入鼓泡反应器,在 相似文献
8.
9.
甲缩醛反应精馏过程模拟 总被引:4,自引:0,他引:4
通过实验取得了甲醛和甲醇合成甲缩醛的反应参数;建立了其连续生产工艺的数学模型,利用ASPEN PLUS软件对甲醛和甲醇缩合生成甲缩醛进行了模拟,结果表明反应精馏连续生产甲缩醛的工艺是可行的,转化率高达99%,并得到含甲缩醛99%的产物,同时确定了进料板和反应区. 相似文献
10.
11.
12.
分析国内外乙炔、乙醇、丁烷、石脑油、乙烯、甲醇等原料生产醋酸工艺路线的历史过程和发展趋势并优选醋酸原料。采用煤或天然气产品甲醇作为醋酸原料的比重愈来愈高。低压甲醇羰基合成法生产醋酸工艺流程先进、产品收率高、综合能耗低,该技术代表当前醋酸生产的最新工艺和发展方向。由于新金属材料的出现,仪表控制水平的提高,低压甲醇羰基合成生产醋酸的技术已日臻完善。随着大型醋酸装置的投产,我国醋酸市场将出现供大于求的态势。 相似文献
13.
José Antonio Delgado Dobladez Vicente Ismael Águeda Maté Dora Lucía Uribe Santos Silvia Álvarez Torrellas Marcos Larriba 《分离科学与技术》2019,54(6):930-942
This work aims to study the citric acid recovery from an aqueous mixture by an adsorption process using a Reillex® 425 resin as adsorbent and methanol as desorbent. A theoretical model has been developed to describe the aqueous citric acid adsorption on Reillex® 425 and its desorption with methanol. An SMB process for recovering citric acid from a citric acid/water mixture containing 10% w/w of citric acid using methanol as desorbent has been designed and optimized, with purity above 99% and recovery above 95%. An evaporation–crystallization method is designed to recover citric acid and methanol from the extract. 相似文献
14.
The Herter process is a patented enhanced oil recovery process that proposes the use of a fatty acid as a solvent to recover petroleum from an oil reservoir or a tar sand. The fatty acid solvent is injected into a reservoir formation or mixed with a tar sand in order to reduce the viscosity and increase the mobility of the petroleum.
The recovery and recycle of the fatty acid solvent are fundamental parts of the process. The Herter process proposes to recover the fatty acid by saponification, migration of the soap to the aqueous phase, and desaponification of the resulting soap phase. However, the formation of a hydrocarbon-soap-water emulsion severely limits the proposed process. Addition of methanol limits emulsification to allow a meaningful separation to be accomplished.
An evaluation of two proposed revisions to the Herter process was made based on batch experiments involving the recovery of oleic acid, linolenic acid, and Georgia Pacific XTOL™304 fatty acid from solvated mixtures with n-heptane. In both of these methods, methanol was introduced to the process as a cosolvent for the saponifying base (sodium hydroxide). The two methods differed in the manner of methanol recovery. In method 1, the saponification heavy phase was distilled to recover methanol. In method 2, the desaponification heavy phase was distilled to recover methanol.
Both of these methods had fatty acid recoveries greater than 84%, n-heptane recoveries greater than 89%, and methanol recoveries greater than 67%. Method 1 recovered purer fatty acid and a slightly greater percentage of n-heptane. Method 2 recovered a greater percentage of both fatty acid and methanol. Method 2 was found to be superior when high purity of the recovered fatty acid product was not required. 相似文献
The recovery and recycle of the fatty acid solvent are fundamental parts of the process. The Herter process proposes to recover the fatty acid by saponification, migration of the soap to the aqueous phase, and desaponification of the resulting soap phase. However, the formation of a hydrocarbon-soap-water emulsion severely limits the proposed process. Addition of methanol limits emulsification to allow a meaningful separation to be accomplished.
An evaluation of two proposed revisions to the Herter process was made based on batch experiments involving the recovery of oleic acid, linolenic acid, and Georgia Pacific XTOL™304 fatty acid from solvated mixtures with n-heptane. In both of these methods, methanol was introduced to the process as a cosolvent for the saponifying base (sodium hydroxide). The two methods differed in the manner of methanol recovery. In method 1, the saponification heavy phase was distilled to recover methanol. In method 2, the desaponification heavy phase was distilled to recover methanol.
Both of these methods had fatty acid recoveries greater than 84%, n-heptane recoveries greater than 89%, and methanol recoveries greater than 67%. Method 1 recovered purer fatty acid and a slightly greater percentage of n-heptane. Method 2 recovered a greater percentage of both fatty acid and methanol. Method 2 was found to be superior when high purity of the recovered fatty acid product was not required. 相似文献
15.
The oxidation of trimethoxymethane (TMM) (trimethyl orthoformate) in a direct oxidation PBI fuel cell was examined by on-line mass spectroscopy and on-line FTIR spectroscopy. The results show that TMM was almost completely hydrolyzed in a direct oxidation fuel cell which employs an acid doped polymer electrolyte to form a mixture of methylformate, methanol and formic acid. It also found that TMM was hydrolyzed in the presence of water at 120°C even without acidic catalyst. The anode performance improves in the sequence of methanol, TMM, formic acid/methanol, and methylformate solutions. Since formic acid is electrochemically more active than methanol, these results suggest that formic acid is probably a key factor for the improvement of the anode performance by using TMM instead of methanol under these conditions. 相似文献
16.
用磷钼酸修饰甲醇燃料电池的铂电极 总被引:1,自引:0,他引:1
近年来以杂多化合物为基础的催化体系受到广泛的关注.为了研究杂多酸与铂电极对甲醇电催化氧化的协同效应,通过循环伏安扫描法制备了磷钼酸(H3PMo12O40)修饰铂电极.通过循环伏安和计时电流法研究了该修饰电极对甲醇氧化的电催化活性和抗中间产物的毒化作用,并比较了该修饰电极与其单酸盐(Na2MoO4)修饰铂电极的性能,测试结果表明:磷钼酸修饰铂电极能够提高对甲醇氧化反应的催化活性,基本上同其单酸盐Na2MoO4修饰铂电极的催化活性相当,并且这种促进作用主要是由Mo原子价态变化引起的.同时计时电流曲线测试结果表明,该修饰电极具有一定的抗毒化作用,但不如钼酸钠好. 相似文献
17.
18.
19.
水杨酸甲酯的加压合成工艺研究 总被引:1,自引:0,他引:1
以水杨酸和甲醇为原料,对甲苯磺酸催化作用下合成了水杨酸甲酯,考察了酸醇摩尔比、反应温度、反应时间及反应压力对酯收率的影响。结果表明,较佳合成工艺条件为:n(水杨酸)∶n(甲醇)摩尔比=1∶5,反应温度120℃,反应时间5 h,反应压力162 kPa,在此条件下,酯收率接近90.0%。产品经FT-IR确定结构,用气相色谱检测,产品纯度达到99.5%。 相似文献
20.
低温甲醇洗装置洗涤甲醇消耗偏高的原因及对策 总被引:1,自引:0,他引:1
介绍了低温甲醇洗装置在试车过程中存在的问题,分析了装置中洗涤甲醇消耗偏高的原因,提出解决问题的办法。系统调整及技术改造后,降低了装置排放气体中的甲醇夹带量,合成气和酸气中的甲醇夹带量也明显减少,效果显著。 相似文献