蔗糖酯水溶剂法合成工艺研究

采用水溶剂法合成蔗糖单硬脂酸酯适宜的反应条件为 :蔗糖与硬脂酸单甘酯摩尔比为 3∶ 1、乳化剂用量5%、催化剂用量 5%、水用量 10 %、反应温度 150℃、反应时间 4 h、压力 0 .0 7～ 0 .14 Pa。重量收率 111.5% (以硬脂酸单甘酯计 )     

3,4-二羟基钠-2,5-二甲酸二乙酯噻吩的合成

以硫代二甘酸二乙酯和草酸二乙酯为原料,乙醇为溶剂,在乙醇钠的作用下,经Claisen酯缩合反应制备3,4-二羟基钠-2,5-二甲酸二乙酯噻吩。研究了物料配比、反应温度、反应时间及加料方式对反应速率及产物收率的影响。较佳反应条件为:n(硫代二甘酸二乙酯)∶n(草酸二乙酯)∶n(乙醇钠)=1∶1.25∶2.5,将硫代二甘酸二乙酯、草酸二乙酯与60mL乙醇的混合物滴加到溶有乙醇钠的240mL乙醇中,反应温度78℃,反应时间4h,3,4-二羟基钠-2,5-二甲酸二乙酯噻吩的收率达98.4%,纯度99.5%以上。     

阻燃剂赛克三硅酸二氯丙酯的合成

以SiCl4、三(2-羟乙基)异氰尿酸酯(赛克)和环氧氯丙烷为原料合成了有机硅酸酯阻燃剂三[2-三(二氯丙氧基)硅酰氧基乙基]异氰尿酸酯(简称赛克三硅酸二氯丙酯)。考察了溶剂种类、反应温度和反应物配比对合成反应的影响,得到了最佳的反应条件,并采用FTIR、1H NMR、TG-DTA分析及极限氧指数等技术表征了产物的结构和性能。最佳的反应条件为:n(SiCl4)∶n(环氧氯丙烷)∶n(赛克)=3∶9.8∶1,SiCl4先与环氧氯丙烷在50℃下反应2 h,再与赛克在90℃下反应9 h,最后与环氧氯丙烷于90℃下反应6 h。在此条件下,赛克三硅酸二氯丙酯的收率为93.7%。性能测试结果表明,该产物阻燃效能高,与聚氯乙烯的相容性好,适合用作聚氯乙烯等材料的阻燃剂。     

一锅法合成异氰尿酸三苄基酯

对以尿素为原料一锅法制备异氰尿酸三苄基酯的合成反应进行了研究。首先由尿素通过液相法合成异氰尿酸。不经分离继续与苄氯和三乙胺反应生成异氰尿酸三苄基酯。对反应条件及影响产率的各种因素进行了讨论。     

环保增塑剂2,2,4-三甲基-1,3-戊二醇二异丁酸酯的合成

采用共结晶法制备了一系列复合无机盐催化剂,研究异丁酸和2,2,4-三甲基-1,3-戊二醇单异丁酸酯合成2,2,4-三甲基-1,3-戊二醇二异丁酸酯的反应。考察了催化剂用量、混合无机盐的配比、醇酸比、反应温度、反应时间、催化剂重复性等工艺条件对反应的影响。实验结果表明,NaHSO_4·H_2O-NaH_2PO_4复合无机盐催化剂具有酯化率高和重复效果好等优点。经单因素实验考察,确定最优的工艺条件为:催化剂用量为2,2,4-三甲基-1,3-戊二醇单异丁酸酯质量的5%,醇酸摩尔比为1∶1.5,反应温度为160℃,反应时间为6h。在此条件下,2,2,4-三甲基-1,3-戊二醇单异丁酸酯的转化率为94.6%,选择性为96.5%,催化剂可重复使用7次以上,具有工业化应用前景。     

戊二酸二壬酯的杂多酸催化合成

以杂多酸为催化剂,从二羧酸中分离出戊二酸,再和壬醇反应,合成戊二酸二壬酯。考察了醇酐摩尔比、反应温度、反应时间、催化剂用量等反应条件对酯化反应的影响,确定了合成戊二酸二壬酯的工艺条件,并对目的产物进行了红外光谱测定,按照国家标准,测定了戊二酸二壬酯的一些性能指标。     

催化加氢制备三(4-氨基苯基)硫代磷酸酯工艺条件的改进

以对硝基苯酚和三氯硫磷合成反应制得的三(4-硝基苯基)硫代磷酸酯为原料,催化加氢还原制备三(4-氨基苯基)硫代磷酸酯。通过对溶剂种类、催化剂型号及用量、反应温度、反应压力等工艺条件的研究,得出如下较佳的工艺条件:以甲醇为溶剂,Raney-N i为催化剂,反应温度70℃、反应压力2.0~3.0M Pa。所得成品纯度大于94%。通过补加少量新鲜催化剂,催化剂能够重复使用并且性能稳定。     

非酸催化合成新型增塑剂偏苯三酸三(2-乙基)己酯

用钛酸四丁酯催化合成偏苯三酸三(2-乙基)己酯,研究了催化剂的选择性和用量、偏苯三酸酐和2-乙基己醇的原料配比、反应温度对酯化反应的影响,确定了最佳工艺条件:偏酐:2-乙基己醇为1:4(ml);反应温度210℃;反应时间3h;催化剂用量0.96‰。     

非酸催化合成新型增塑剂偏苯三酸三(2-乙基)己酯

用钛酸四丁酯催化合成偏苯三酸三(2-乙基)己酯,研究了催化剂的选择性和用量、偏苯三酸酐和2-乙基己醇的原料配比、反应温度对酯化反应的影响,确定了最佳工艺条件:偏酐:2-乙基己醇为1:4(ml);反应温度210℃;反应时间3h;催化剂用量0.96‰。     

锡类催化剂催化合成癸二酸二异辛酯

以锡类化合物催化癸二酸和异辛醇为原料合成了癸二酸二异辛酯,以GM-1为催化剂考察了反应条件对酯化反应的影响。在反应温度190℃,原料配比n(癸二酸)∶n(异辛醇)=1∶2.4,w(催化剂)=0.05%,反应时间7h条件下,酯化反应转化率99.5%以上,高温脱醇过程中粗酯的性能稳定。粗酯直接过滤即可得到产品,处理方法简单,不需要蒸馏,不产生液废和固废,催化剂可以重复使用。     

Methodology for Predicting the Phase Envelope of a Heavy Crude Oil and Its Asphaltene Deposition Onset

Abstract

We have presented general ideas to develop a new theoretical methodology, based on molecular simulation and equations of state, for obtaining the phase envelope and to predict pressure, volume, temperature (PVT) conditions of asphaltene precipitation by only taking into account the composition of the heavy crude oil and an asphaltene average molecular structure. Those results show that asphaltene precipitation is a reversible thermodynamic process. The precipitated phase is a liquid phase which consists of mainly asphaltene and some heavy fractions from the crude. This methodology can be applied to find complete phase diagrams of different crude oils based on an asphaltene average molecular structure and the composition of crude oil.     

活性自由基引发星形PMA黏度指数改进剂合成及其剪切稳定性研究

通过可逆-加成断裂链转移( RAFT)活性自由基聚合得到了主要成分为聚甲基丙烯酸酯类化合物的星形聚合物黏度指数改进剂,其中星形结构的臂数不小于3,其臂的分子量具有可控且分布窄的特点.通过圆锥滚子轴承法对其抗剪切性能进行了评价,结果显示所合成的星形聚合物黏度指数改进剂与组成类似的线性聚合物相比,在增稠能力相当时,所合成的星形聚合物具有优良的抗剪切能力;在增粘程度和抗剪切性能相当的情况下,只需要很少的加剂量.     

高温熔盐合成TiC-NiTi复合粉末体系的研究

以Ti粉、Ni粉和活性炭为原料,用高温熔盐的方法合成的TiC-NiTi复合粉体中的NiTi相不但具有良好的可逆马氏体相变行为,而且马氏体转变相变温度与大块NiTi材料基本相同。虽然合成粒子大部分团聚成大颗粒,但粒子的形貌比较规则。对合成的复合粉体进行高温盐水浴处理后的产物中虽然有TiC大量存在,但是NiTi仍然具有可逆马氏体相变效应,并且随着保温时间的延长,可逆马氏体相变行为更加稳定。高温处理后的粉体粒子团聚成大颗粒,其中TiC粒子呈片层状。     

RAFT聚合制备嵌段聚合物结构对降滤失剂性能的影响

为了探究聚合物结构对降滤失剂性能的影响,选用AMPS作为阴离子组分、离子液体1-乙烯基-3-乙基咪唑溴盐（VeiBr）作为阳离子组分及AM作为中性组分,采用可逆加成断裂链转移自由基（RAFT）聚合法合成了一系列组成相同而结构不同的两性离子降滤失剂。通过调节单体加入顺序合成了3种结构精确、键接顺序不同、分子量分布窄且可控的聚合物结构,即无规共聚物、部分嵌段共聚物和完全嵌段共聚物,并评价了其流变性能、降滤失性能。结果显示在其他条件相同的条件下,无规分布聚合物的降滤失效果最好,而嵌段聚合物可用于制备高动塑比的流型调节剂。通过改变链转移剂加量,精确调节聚合物分子量,进一步分析了同一聚合物结构下不同分子量对其性能的影响。结果表明分子量越大,聚合物整体呈现黏度增大、降滤失性能得到改善的趋势。因此,无规序列结构的嵌段聚合物在钻井液降滤失剂中性能较好,同时分子量越大的聚合物更加具有优势,该研究为从结构出发研发高效降滤失剂提供了理论基础。      

硫化Mo/CNT催化剂上甲醇与醋酸甲酯可逆吸附热的测定

本文采用相对保留体积测定了甲醇与醋酸甲酯在碳纳米管载体以及硫化的Mo/CNT催化剂上的可逆吸附热。在碳纳米管载体上,甲醇与醋酸甲酯的可逆吸附热分别为16 0kJ/mol和34 1kJ/mol;在硫化的Mo/CNT催化剂上,甲醇与醋酸甲酯的可逆吸附热分别为15 3kJ/mol和26 1kJ/mol。随温度升高醋酸甲酯的可逆吸附量比甲醇的可逆吸附量下降快,在反应条件下甲醇的可逆吸附量比醋酸甲酯的大8～10倍,甲醇在催化剂上吸附后进行反应,产物醋酸甲酯迅速脱附,从而有利于羰基化反应进行。     

S,S′-二(α,α′-甲基-α′′-乙酸)三硫代碳酸酯存在下的热聚合反应及光聚合反应

合成了S,S′-二(α,α′-甲基-α′′-乙酸)三硫代碳酸酯(TRIT),以TRIT为可逆加成-裂解链转移(RAFT)聚合反应的链转移剂,对苯乙烯(S t)和甲基丙烯酸甲酯(MMA)单体的热聚合反应和室温下光引发的聚合反应进行了研究,用凝胶渗透色谱、核磁共振(1H NMR)和傅里叶变换红外光谱(FTIR)等方法对热聚合反应和光聚合反应所得聚合物的结构和相对分子质量及其分布进行了表征。实验结果表明,聚合反应具有明显的活性特征,聚合物的相对分子质量分布较窄,相对分子质量随转化率的增加呈线性增加,ln[M]0/[M](M为单体)随聚合反应时间的延长也呈线性增加,聚合物分子链中含有三硫代碳酸酯基。根据1H NMR和FTIR的分析结果,初步提出了光聚合反应机理。     

The Asphaltene and Wax Deposition Envelopes

Asphaltene and wax phase behavior is quite different than the conventional “PVT” phase behavior. Asphaltenes exhibit a behavior at some thermodynamic states called flocculation. That is, asphaltene particles or micelles aggregate or flocculate into larger aggregates or flocs. The locus of all thermodynamic points in a P-T-x phase diagram at which flocculation occurs is called the Asphaltene Deposition Envelope (ADE). Paraffin waxes, on the other hand, at some thermodynamic states, exhibit the phenomenon of crystallization. The locus of all thermodynamic points in a P-T-x phase diagram at which wax crystallization occurs is called the Wax Deposition Envelope (WDE). Asphaltene flocculation can be both reversible and irreversible (as expected from the asphaltene colloidal nature). Wax crystallization is generally a reversible process. However, paraffin waxes more than often precipitate together with resins and asphaltenes (which are said to be responsible for the observed irreversible thermodynamic phenomena). Hence, some wax precipitation is occasionally reported as irreversible. Measurement of the ADE and WDE boundaries, at in-situ conditions, is a challenging task. Measurement of asphaltene and wax solubility at in-situ conditions inside the ADE and WDE is even more challenging. The ADE and WDE data have practical significance and are very useful for modeling of reservoir fluid behavior. Asphaltene and wax data for a number of oils are presented and analyzed. This paper introduces and compares two powerful thermodynamic diagrams that summarize the phase behavior of asphaltenes and waxes, the ADE and WDE.     

Mechanism of the reversibility of asphaltene precipitation in crude oil

Asphaltene precipitation and deposition occur in petroleum reservoirs as a change in pressure, temperature and liquid phase composition and reduce the oil recovery considerably. In addition to these, asphaltene precipitates may deposit in the pore spaces of reservoir rock and form plugging, which is referred to as a type of formation damage, i.e. permeability reduction. In all cases above, it is of great importance to know under which conditions the asphaltenes precipitate and to what extent precipitated asphaltenes can be re-dissolved. In other words, to what extent the process of asphaltene precipitation is reversible with respect to change in thermodynamic conditions. In present work, a series of experiments was designed and carried out to quantitatively distinguish the reversibility of asphaltene precipitation upon the change in pressure, temperature and liquid composition. Experiments were conducted in non-porous media. Generally it was observed that the asphaltene precipitation is a partial reversible process for oil under study upon temperature change with hysteresis. However, the precipitation of asphaltene as a function of mixture composition and pressure is nearly reversible with a little hysteresis.     

The Asphaltene and Wax Deposition Envelopes

ABSTRACT

Asphaltene and wax phase behavior is quite different than the conventional “PVT” phase behavior. Asphaltenes exhibit a behavior at some thermodynamic states called flocculation. That is, asphaltene particles or micelles aggregate or flocculate into larger aggregates or flocs. The locus of all thermodynamic points in a P-T-x phase diagram at which flocculation occurs is called the Asphaltene Deposition Envelope (ADE). Paraffin waxes, on the other hand, at some thermodynamic states, exhibit the phenomenon of crystallization. The locus of all thermodynamic points in a P-T-x phase diagram at which wax crystallization occurs is called the Wax Deposition Envelope (WDE). Asphaltene flocculation can be both reversible and irreversible (as expected from the asphaltene colloidal nature). Wax crystallization is generally a reversible process. However, paraffin waxes more than often precipitate together with resins and asphaltenes (which are said to be responsible for the observed irreversible thermodynamic phenomena). Hence, some wax precipitation is occasionally reported as irreversible. Measurement of the ADE and WDE boundaries, at in-situ conditions, is a challenging task. Measurement of asphaltene and wax solubility at in-situ conditions inside the ADE and WDE is even more challenging. The ADE and WDE data have practical significance and are very useful for modeling of reservoir fluid behavior. Asphaltene and wax data for a number of oils are presented and analyzed. This paper introduces and compares two powerful thermodynamic diagrams that summarize the phase behavior of asphaltenes and waxes, the ADE and WDE.     

基于乳状液转相技术的钻井液新体系室内研究

为有效解决油基钻井液应用中存在的固井质量较差、环境污染严重等问题,采用有机胺质子化可逆原理,赋予油基钻井液以乳化相态的可逆性,研制了一套可逆乳化钻井液体系。该钻井液体系的配方为5#白油+25.0%CaCl2溶液+1.0%有机土+0.5%石灰+1.0%润湿剂RS+4.0%乳化剂ET,油水比为50:50,密度为1.2 kg/L。通过室内试验对该钻井液体系进行了全面的性能评价,结果表明,通过酸触相反转和碱触相回转,可实现W/O型与O/W型间自由转换;且转换前后的钻井液性能良好:破乳电压达500~900 V,抗温达180 ℃,高温高压滤失量小于15 mL,流变性与传统逆乳化钻井液相当,可抗10%硫酸钙、20%钻屑污染,渗透率恢复率和滚动回收率都达90%以上,泥饼和含油钻屑更易处理。这说明,研制的可逆乳化钻井液体系兼备油基钻井液和水基钻井液的优点,且各项性能均为优良,能解决常规油基钻井液应用中存在的问题。