双缩乙二胺Schiff碱的合成及其酸化缓蚀性能

以乙二胺和芳香醛为原料合成了乙二胺双缩肉桂醛(NDCE)、乙二胺双缩苯甲醛(NDBE)、乙二胺双缩水杨醛(NDSE)和乙二胺双缩对二甲胺基苯甲醛(NDDE)四种双缩Schiff碱缓蚀剂,用元素分析和红外分析对其结构进行了表征,并采用静态失重法和电化学法研究了90℃时它们在15%(质量分数,下同)HCl中对N80钢的缓蚀性能。结果表明:NDCE的缓蚀效果最好,当NDCE的加量为0.75%时,缓蚀率达到99.17%,且NDCE在N80钢片表面的吸附行为符合Langmuir吸附等温模型;NDCE是一种混合型酸化缓蚀剂,在N80钢表面形成了一层保护膜,有效抑制了酸液对N80钢的腐蚀。     

H_2SO_4中香兰素在钢表面上的吸附及缓蚀作用

用失重法研究了在1.0 mol/L H2SO4中10～40℃香兰素(4-羟基-3-甲氧基-苯甲醛)在冷轧钢表面上的吸附及缓蚀作用.结果表明,香兰素对钢的缓蚀率随香兰素的浓度增加而增大,而随温度的增加而减小;香兰素在钢表面的吸附符合Temkin吸附模型.通过吸附理论和动力学Arrhenius公式分别求出了相应的吸附热力学参数(吸附自由能△G0,吸附热△HO,吸附熵△S0)和动力学参数(表观活化能Ea,指前因子A),并根据这些参数讨论了缓蚀作用机理.     

稀土离子和香兰素在H_2SO_4溶液中对冷轧钢的缓蚀协同效应

用失重法研究了四种稀土离子(La3+,Ce3+,Ce4+,Nd3+)和香兰素(4-羟基-3-甲氧基-苯甲醛)在1.0 mol/LH2SO4介质中对冷轧钢的缓蚀协同效应。结果表明,香兰素对冷轧钢有中等程度的缓蚀作用,缓蚀率随其浓度的增加而增大;四种稀土离子对冷轧钢的缓蚀作用均较差,最大缓蚀率仅为20%左右。香兰素和稀土Ce4+复配后对冷轧钢产生了明显的缓蚀协同效应,最大缓蚀率可达95%左右;而与La3+,Ce3+和Nd3+复配后均无缓蚀协同效应。     

新型苯并咪唑衍生物的合成及其缓蚀行为

采用地沟油水解副产物甘油和多聚甲醛制备了1,3-二氧杂环戊-4-酸(DIC)中间体,再使用DIC与邻苯二胺及其衍生物进行酰胺化-环化反应合成了三种新的目标产物2-(1',3'-二氧五环-4'-基)苯并咪唑(OBCI)、1-甲基-2-(1',3'-二氧五环-4'-基)苯并咪唑(MBCI)和1-苯基-2-(1',3'-二氧五环-4'-基)苯并咪唑(PBCI);采用浸泡试验、电化学试验和扫描电子显微镜(SEM)等研究了这三种化合物在5%(质量分数)HCl溶液中对Q235钢的缓蚀作用。结果表明:三种缓蚀剂在5%HCl溶液中对Q235钢都具有良好的缓蚀效果,缓蚀率随着缓蚀剂含量的增加而增大,当缓蚀剂质量浓度为100mg/L时,失重法测得的最大缓蚀率均超过97%;三种缓蚀剂在Q235钢表面的吸附规律均符合Langmiur吸附等温式,吸附过程为自发进行的化学吸附。     

一种双缩水合肼Schiff碱的合成及其酸化缓蚀性能

以水合肼和肉桂醛为原料合成了一种新型Schiff碱酸化缓蚀剂(DCH),用红外光谱法(FI-RT)、化学元素分析法和核磁共振法对其结构进行表征;通过静态失重法和电化学方法考察了其在15%(质量分数,下同)HCl中对N80钢的缓蚀作用。结果表明:DCH是一种混合型酸化缓蚀剂,可在N80钢表面形成保护膜,有效抑制酸液的腐蚀;当DCH加入量为0.75%时,N80钢的腐蚀速率为2.27g·m~(-2)·h~(-1),缓蚀率高达99.81%;DCH在N80钢表面的吸附规律符合Langmuir吸附模型。     

麻竹竹叶提取物在酸性介质中对冷轧钢的缓蚀作用

从麻竹(Dendrocalmus latifcorus Munro)竹叶中提取出的固体物质,可以作为一种环境友好型植物缓蚀剂。用失重法研究了麻竹竹叶提取物在1.0 mol/L HCl1、.0 mol/L H2SO4和1.0 mol/L H3PO4三种酸性溶液中对冷轧钢的缓蚀作用。结果表明:麻竹竹叶提取物对冷轧钢的缓蚀率随缓蚀剂浓度的增加而增大,当其浓度为200 mg/L时,三种酸溶液中的缓蚀效率可分别达到92.3%(HCl)、88.9%(H2SO4)、75.8%(H3PO4)。且在钢表面的吸附符合校正的Langmuir吸附等温式。并根据试验结果探讨了缓蚀机理。     

氨基磺酸中肉桂醛缩甲胺席夫碱的缓蚀行为研究

合成了缓蚀剂肉桂醛缩甲胺席夫碱,并用傅里叶红外光谱仪对其进行定性检测。采用失重法、动电位极化曲线、电化学阻抗谱(EIS)和扫描电镜(SEM)研究了该席夫碱在5%(质量分数)氨基磺酸介质中对Q235钢的缓蚀行为。结果表明,肉桂醛缩甲胺席夫碱在70℃下具有很好的缓蚀效果,是一种混合型缓蚀剂,在Q235钢表面的吸附符合Langmuir等温式,主要为化学吸附。     

席夫碱对20#碳钢在盐酸介质中的缓蚀作用

分别采用失重法和电化学方法测定了席夫碱试剂4-羟基-3-甲氧基苯甲醛缩-4-烯丙基-3-硫代氨基脲(以下简称AAT),和苯甲醛缩-4-烯丙基-3-硫代氨基脲在盐酸介质中对20#碳钢的缓蚀作用。研究了浓度、温度等因素对这两种缓蚀剂缓蚀性能的影响。结果表明,两种席夫碱试剂在盐酸介质中对20#碳钢均有缓蚀作用,其中AAT的缓蚀性能较优,并发现AAT与乌洛托品、碘化钾、苯甲醛缩-4-烯丙基-3-硫代氨基脲、N-苯甲酰基硫脲等有很好的协同作用。     

盐酸溶液中胺醛缩聚物对Q235钢的缓蚀性能影响

采用化学氧化法合成了胺醛缩聚物,并利用扫描电镜(SEM)、红外光谱(FTIR)测定该聚合物的结构和形貌.采用失重、极化曲线及电化学阻抗法研究胺醛缩聚物对Q235钢在1.0 mol/L的HCl溶液中的缓蚀性能.结果表明:胺醛缩聚物为阳极型缓蚀剂,在Q235碳钢表面形成保护膜,减缓金属的腐蚀.     

席夫碱基咪唑啉化合物对A3钢在盐酸介质中缓蚀性能研究

合成了BIA、BIOHA、BIMHA和BIMMA 4种席夫碱基咪唑啉化合物.用失重法和电化学方法研究了4种席夫碱基咪唑啉化合物对A3钢在盐酸介质中的缓蚀性能和吸附行为.结果表明,在1 mol/L HCl介质中4种化合物对A3钢均有缓蚀作用,它们的缓蚀能力大小为:BIA＞BIMMA＞BIOHA＞BIMHA.4种化合物均属于混合型缓蚀剂,但对阳极的缓蚀作用略大.4种化合物在A3钢表面上的吸附过程为放热过程,其吸附行为服从Langmuir吸附等温式,属于物理吸附.     

3-氨基-1,2,4-三氮唑及3-氨基-1,2,4-三氮唑并芳香醛类希夫碱自组装膜对碳钢在0.5mol/L盐酸中的缓蚀性能研究

目的通过自组装技术在碳钢表面得到3-氨基-1,2,4-三氮唑及3种3-氨基-1,2,4-三氮唑并芳香醛类希夫碱的三种自组装膜,提高碳钢在0.5 mol/L HCl溶液中的缓蚀性能。方法采用电化学方法如电化学阻抗谱、tafel极化曲线等研究席夫碱类自组装膜在盐酸中的电化学参数,如阻抗变化、腐蚀电位、腐蚀电流。采用XPS方法对自组装膜的成分进行表征。结果计算自组装膜在盐酸溶液中的最高缓蚀效率达到92.72%,XPS测试表明自组装分子与金属原子以化学键的方式结合。结论 3-氨基-1,2,4-三氮唑及3种3-氨基-1,2,4-三氮唑并芳香醛类希夫碱自组装膜均对碳钢在盐酸中有良好的缓蚀性能,缓蚀效率的大小与分子结构有关,分子中的O、N杂原子、卤素基团、三唑环及苯环等有利于自组装膜的形成。     

Corrosion inhibition of mild steel by schiff base compounds in various aqueous solutions: part 1

The corrosion inhibition by Schiff base compounds derived from diamines and o-hydroxy, o-methoxy aromatic aldehydes was investigated by weight loss, electrochemical measurements and surface analysis of SS 400 in various aqueous solutions such as tap water (LC), concentrated tap water (HC) and HCl solutions. The maximum inhibition efficiency (η) of N,N′-bis (salicylaldehyde)-1,12-diaminododecane (Saldn) for SS 400 in HCl solution approached 93%. The adsorption of Saldn on mild steel in HCl solution was obeyed Langmuirs isotherm.     

Corrosion Inhibitors for Aluminium Alloys

Data (including literature data) are presented on the inhibition of the corrosion of Al and some Al alloys in hydrochloride, sulfuric, acetic and oxalic acids and sodium hydroxides. In this context the influence is shown of parameters such as inhibitors structure and concentration, temperature, time, medium concentration and external currents. Inhibitors dealt with include aliphatic and aromatic amines, carbonyl compounds (aldehydes, ketones); in this context it is shown that functional groups and their relative positions may have an important effect on inhibitor efficiencies.     

Inhibitoren der Korrosion 23 (1) – Gibt es eine Struktur- Wirkungs-Beziehung bei organischen Inhibitoren der Korrosion von Aluminium?

Corrosion inhibitors 23 (1) – Does there exist a structure-efficiency relation in the organic inhibitors of aluminium corrosion? Over 400 organic compounds have been routinely tested as potential inhibitors for the corrosion and dissolution of aluminium in In HCl/2,5% NaCl solution, using 10^?2 m/l as the concentration of the organic compound being tested. It was attempted to derive a relationship between efficiency of the inhibitor with molecular structure. Particular attention was devoted to the following classes of compound: organoarsenic; phosphonic and phosphinic acids; aromatic aldehydes and ketones; aromatic and aliphatic carboxylic acids; dihydric phenols; tetrazolium salts and formazan compounds; sulphoxides and aromatic sulphonic acids; sulphonamides and sulphones. For a selected number if inhibitors, the dependence of concentration and the effect of an oxygen-containing atmosphere were studied. Compounds which show good inhibition in the corrosion of aluminium are consistently even better in the protection of zinc surfaces. The mechanism of the corrosion inhibition is not clear, but the results suggest that the total molecular structure of the inhibitor must be considered, with particular importance paid to the nature and the spatial relationship of the different functional groups.     

塔河油田单井注采交替缓蚀剂的筛选与复配研究

目的有效治理注采交替工况对井下管柱造成的严重腐蚀,促进缓蚀剂技术在塔河油田的广泛应用。方法采用红外光谱法验证了四种有机缓蚀剂的主要成分,测试了缓蚀剂的理化性能,采用失重法评价了缓蚀剂在塔河油田井下注采交替工况的缓蚀效率,并利用电化学方法研究了两种缓蚀剂的复配性能。结果四种缓蚀剂的有效成分分别为油酸酰胺、芳香酮曼尼希碱、油酸咪唑啉和苄基喹啉盐,理化性能测试全部通过。其中,芳香酮曼尼希碱和油酸咪唑啉在井下注采交替工况下具有良好的缓蚀性能,缓蚀效率分别达到73%和67%。油酸咪唑啉和芳香酮曼尼希碱的复配能进一步提升缓蚀效率,当芳香酮曼尼希碱和油酸咪唑啉的质量比为1:3时,复配缓蚀剂的缓蚀效率能达到90%。结论芳香酮曼尼希碱-油酸咪唑啉复配型缓蚀剂是一种适用于塔河油田注采交替工况的缓蚀剂。     

The influence of some aldehydes on the corrosion and anodic behaviour of aluminium in sodium hydroxide solution

A set of aliphatic and aromatic aldehydes has been examined for their effectiveness in preventing the corrosion of aluminum (2S) in 1M NaOH solution and their influence on the anodic polarization behaviour. It has been found that the aromatic compounds are generally more effective as corrosion inhibitors than the aliphatic inhibitive nature of a solution.     

Korrelationsbetrachtungen zum Einfluß von Säureinhibitoren auf die Metallauflösungsgeschwindigkeit und die Kinetik der Wasserstoffabsorption

Considerations on the correlations between inhibition of metal dissolution and hydrogen absorption in the use of acid inhibitors Evaluating literature data on the impact of 53 quarternary ammonium salts, 13 aliphatic and aromatic aldehydes and 12 aliphatic and aromatic ketones on the inhibition of the rate of metal dissolution and the hydrogen permeation currents at steel in H₂S-free and H₂S-saturated 16% hydrochloric acid at ambient temperature, it is demonstrated by rank correlation considerations that there is no correlation between activity in blocking the metal dissolution rate and efficiency in decreasing the hydrogen absorption rate of the metal. Furthermore, there is no correlation between antipromotor/promotor-efficiency at the free corrosion potential and at cathodic polarization in H₂S-free and H₂S-saturated acid. Problems of H-absorption therefore have to be investigated for any particular case under conditions as close to the practice as possible.     

The mechanism of the inhibition of zinc corrosion in 1N HCl solution by tetraphenylphosphonium bromide

A number of organic corrosion inhibitors of zinc were tested in a 1N HCl medium by the weight loss method. The tafel cathodic slopes relating to solutions containing conventional compounds are 120 mV per current density decade, whereas the solution containing tetraphenylphosphonium bromide gives a 240 mV slope. The inhibition mechanism for the latter compound was studied electrochemically as well as by analytical methods, showing its own reduction to be involved with two different processes: (i) phosphorus-carbon bond fracture with subsequent formation of triphenylphosphine oxide, and (ii) aromatic ring reduction. These two types of reduction have opposite effects on the inhibition process: triphenylphosphine and its oxide formed during the inhibition process are strong inhibitors, but the reduction of aromatic rings at the interface favours the desorption of adsorbed compounds and limits their inhibiting efficiency. An insoluble compound such as (Ph₄P)₂ZnCl₄ may increase the inhibition efficiency by precipitation at the interface, or decrease it by precipitation in the solution.     

Aldehydes as corrosion inhibitors for aluminium-manganese alloys in potassium hydroxide

Some aliphatic and aromatic aldehydes have been studied as corrosion inhibitors for 3S aluminium (Al-Mn alloy) in KOH solutions. At constant alkali concentration the inhibitor efficiency increases with the concentration of the inhibitor, the order of efficiency in 0.1 M KOH + 1.0% inhibitor being: paraldehyde (13.3%) < formaldehyde ≦ propionaldehyde < crotonaldehyde < furfuraldehyde < vanillin < salicylaldehyde (74.8%); 0.5% benzaldehyde and 0.1% cinnamicaldehyde gave efficiencies of only 19.3% and 18.5%, respectively. The aldehydes appear to act by adsorption on the metal surface, preferably through the oxygen atom. The inhibitive efficiency of paraldehyde increases with the alkali concentration, the duration of immersion and the temperature; that of formaldehyde, cinnamic aldehyde, furfuraldehyde (and crotonaldehyde) increases with alkali concentration and time; that of salicylaldehyde and vanillin increases with time as well as with temperature, while the efficiency of propionaldehyde and benzaldehyde increases with alkali concentration. The activation energy for the corrosion process is generally higher in inhibited than in plain alkali in the case of formaldehyde, propionaldehyde, crotonaldehyde, benzaldehyde, cinnamicaldehyde and furfuraldehyde; with other inhibitors the E values are lower. Except vanillin and paraldehyde, all the inhibitors increase the corrosion potential of Al in 0.1 M KOH suggesting polarization of local anodes. The inhibitor efficiencies calculated from extrapolation of cathodic Tafel lines are in agreement with weight loss efficiencies.     

Inhibition of steel corrosion by unsaturated aldehydes in solutions of mineral acids

Effect of α,β-unsaturated aldehydes on the corrosion of mild steel in solutions of hydrochloric and sulfuric acids was investigated using gravimetric, voltammetric and chromato-mass spectrometry techniques. General regularities of corrosion and electrochemical behavior of these compounds in solutions of mineral acids are established. The role of the chemical transformation of α,β-unsaturated aldehydes in the inhibition of corrosion is shown.