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甘蔗渣中性亚硫酸钠蒸煮最佳工艺条件的研究 总被引:2,自引:0,他引:2
本文研究了甘蔗渣中性亚硫酸钠制浆的蒸煮最佳工艺条件。研究结果表明,甘蔗渣中性亚硫酸钠蒸煮采用下列工艺条件:Na2SO3用量为18%,Na2CO3用量为3%,液比为1:5,最高温度160℃,升温2小时,保温1小时。在此蒸煮条件下,纸浆得率可达65.83%,高锰酸钾值9.14,白度50%,不透明度92.65%,以及可得到较好的纸浆强度。 相似文献
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利用对甲苯磺酸(PTS)与氢氧化铁(Fe(OH)3)合成了对甲苯磺酸铁(DBF),并讨论了实验中物料配比、反应温度及反应时间对目标产物质量的影响。确定反应的最佳条件为:投加PTS与氢氧化铁物质的量比为1.1:1;反应温度为80℃;反应时间为3h。在此反应条件下,目标产物DBF中PST-与Fe件的物质的量比为8.70:1,收率90.9%。 相似文献
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氟碳烷基琥珀酸酯磺酸盐表面活性剂的合成研究 总被引:1,自引:0,他引:1
以八氟戊醇、顺丁烯二酸酐和亚硫酸钠为原料,经过酯化、磺化步骤,合成了一种新型的阴离子表面活性剂——氟碳烷基琥珀酸酯磺酸盐表面活性剂,并对最佳工艺条件进行探索。结果表明合成马来酸单酯的最佳条件为:八氟戊醇与顺丁烯二酸酐的摩尔比为1:1.2;反应时间为4~5h;反应温度为85~90℃;催化剂用量为八氟戊醇的6%,产品的转化率为98-87%。合成氟碳烷基琥珀酸酯磺酸盐最佳工艺为:马来酸单酯与无水亚硫酸钠的配比为1:1.2;反应时间为卜1.5h;反应温度为75—80℃,产品的转化率为98.70%。该表面活性剂的性能测试结果表明,其临界胶团浓度是5.9×10^-3mol/L,表面张力是24.068mN/m。 相似文献
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N-歧化松香酰基肌氨酸的合成及其性能 总被引:11,自引:0,他引:11
以歧化松香和肌氨酸为主要原料,合成了N-歧化松香酰基肌氨酸。歧化松香先与氯化亚砜反应制得歧化松香酰氯,歧化松香与氯化亚砜的摩尔比为1:2,75℃~80℃下反应1h,歧化松香酰氯收率为88%,熔程:46℃-48℃。歧化松香酰氯再与肌氨酸进行缩合反应,合成N-歧化松香酰基肌氨酸,二次回归正交试验确定的合成条件为:歧化松香酰氯与肌氨酸摩尔比为1.0:1.9,27℃下反应2.75h,反应体系pH控制在8~9,以丙酮与水的混合溶液(体积比为1:1)作为溶剂,产物的收率83.96%。歧化松香酰基肌氨酸钠盐溶液的cmc为5.16mmoL/L,水溶液的pH值为7.9,其发泡能力和乳化能力与K12相近。 相似文献
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以对硝基甲苯为原料经还原,磺化两步反应合成4B酸,通过正交试验确定最佳工艺条件为磺化温度175℃,硫酸与对甲苯胺的摩尔比为1.1:1,活性炭与对硝基甲苯的质量比为1:20,在优化条件下,碘化收率达到93.7%,4B酸的总收率达到83.3%,产品纯度为98%,产品经元素分析、高效液相色谱分析证实了它的结构和纯度。, 相似文献
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对用对甲苯磺酸作催化剂湿法合成异丁叉二脲的反应进行了研究,通过实验,确定了其最佳工艺条件,异丁醛与尿素的用量比为1:2.8(摩尔比),催化剂对甲苯磺酸的用量为1%(对异丁醛的物质的量),反应介质水的用量为6:1(与尿素质量比),反应温度为35℃,反应时间为0.5h,产品产率可达96.5%。 相似文献
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无溶剂法合成蔗糖硬脂酸酯的工艺研究 总被引:7,自引:0,他引:7
以乙醇代替有毒的甲醇与硬脂酸在酸催化下进行反应制出了硬脂酸乙酯。以硬脂酸乙酯与蔗糖为原料在催化剂和乳化剂的作用下,进行酯交换反应合成出蔗糖硬脂酸酯。详细考察了该合成反应过程中乳化剂、催化剂用量,反应温度,原料配比,反应时间等因素对蔗糖硬脂酸酯产率的影响,得出了较佳合成工艺条件,即硬脂酸乙酯:蔗糖摩尔比为2.15:1,乳化剂与蔗糖质量比为0.1:1,催化剂与反应物料质量比为0.14:1,反应温度-120℃,压力-4.35kPa,反应时间-3.5h。以蔗糖计,蔗糖酯产率约75.2%。此外,还把蔗糖硬脂酸酯制成易挥发衍生物,建立了分析其组成的气相色谱方法。 相似文献
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氯酸钠,亚氯酸钠和二氧化氯的制造与应用 总被引:4,自引:0,他引:4
氯酸钠是生产亚氯酸钠和二氧化氯的原料,亚氯酸钠和二氧化氯又是互为转化的原料,三者是关系密切的系列产品。本文介绍了氯酸钠系列产品,包括稳定性二氧化氯,近年迅速发展的缘由,生产概况,制造方法和应用领域。并对这些产品的发展与应用推广提出了建议。 相似文献
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在分析国内外五水偏硅酸钠生产工艺的基础上,利用水溶液结晶法生产五水偏硅酸钠,具有设备简单,易于操作,生产稳定,投资省等优点。 相似文献
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对湖北氧化铁型金矿进行了Na2S2O3法添加NaCl而不加Cu2+的浸取条件优化研究,当[S2O2-3]=0.8mol/L、[NH3]=1~2mol/L、[NaCl]=1.0mol/L、浸取温度50℃、浸取时间为3h时,浸出率达到98%.对广东河台、山东招远硫化金矿进行了浸取研究,当[S2O32-]=0.8mol/L、[NH3]=2mol/L、[NaCl]=1.0mol/L、十二烷基磺酸钠11.0mol/L、浸取温度50℃、浸取时间3h时,浸取率分别达到96%和93%. 相似文献
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Sang Jun Kong Yoon Kyung Bae Ki June Yoon 《Korean Journal of Chemical Engineering》1999,16(2):234-239
Monosodium zirconium phosphate or disodium zirconium phosphate by itself did not catalyze the oxidative coupling of methane
and also the deep oxidation of methane. However, NaCl-added sodium zirconium phosphates showed markedly increased activity
and high C2+ selectivity in the oxidative coupling of methane, which indicates that chlorine species or NaCl plays an essential role in
the catalytic action. The catalytic performance became more stable with increasing content of NaCl. The primary reason for
the catalyst deactivation is the loss of chlorine, and a possible secondary reason is the transformation of catalytic substance
to the sodium zirconium phosphates having higher Na/Zr ratios or decomposition of sodium zirconium phosphates to zirconium
oxide and sodium phosphate. Two kinds of surface chlorine species were observed, and the lower-binding-energy species is considered
to be much more active than the higher-binding-energy species in methane activation, although the latter is present in a larger
amount than the former. 相似文献
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《Ceramics International》2022,48(9):12442-12449
The fly ash geopolymer with improved mechanical properties was prepared by a new mixture alkali activator. In this paper, sodium tert-butanol, an organic strong alkali was used as an activator for preparing fly ash geopolymer to improve their mechanical properties. The effect of activator content and type on the macroscopic level of fly ash geopolymer was investigated experimentally by three types of activators: sodium tert-butanol, sodium silicate, and sodium tert-butoxide/sodium silicate mix activator. The microstructure of the fly ash geopolymer was characterized by ATR-FTIR, SEM-EDS, XRD, and Brunauer-Emmett-Teller (BET) physical adsorption method. The results showed that the new mixture alkali activator prepared by 5% sodium tert-butoxide and 10% sodium silicate improved the denseness and integrity of the microstructure of the fly ash geopolymer. Consequently, the mechanical properties of fly ash geopolymer are improved. The microscopic results demonstrated that the C–OH in tert-butanol after the hydrolysis of sodium tert-butoxide and Si–OH in the geopolymer can form C–O–Si bonds, forming a more complex three-dimensional network structure. This paper reveals the enhancement mechanism of organic alkali as activators for preparing fly ash geopolymer, and provides support for the subsequent development of organic strong alkali activators. 相似文献
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The effect of addition of sulphate to sodium chloride and sodium fluoride melts was investigated by chronopotentiometry in the temperature range 820-1000 °C. It was found that the numerical value of the chronopotentiometric term jτ1/2/c0 increased with increasing cathodic current density. This behaviour was explained by chemical decomposition of sodium sulphate into SO3 and Na2O, followed by electrochemical reduction of SO3. The decomposition of sodium sulphate is enhanced with increasing temperature, resulting in an increase in the chronopotentiometric transition time. Numerical simulation of this electrode process supports this explanation of the electrode process. It is not a classical so-called CE mechanism when a chemical reaction precedes the electrochemical reduction as described in the literature, because the formation of SO3 is suppressed by the presence of Na2O in the melt. 相似文献