【摘要】：鍍鋅設(shè)備在大氣環(huán)境和水質(zhì)環(huán)境中都具有非常好的防腐性,被廣泛的應(yīng)用于食品、化工、石油等行業(yè)的設(shè)備鍍層和陽極保護(hù),尤其是水產(chǎn)業(yè)冷庫設(shè)備、食品加工業(yè)蒸發(fā)冷凝器設(shè)備等。但是,在實(shí)際應(yīng)用中,鍍鋅設(shè)備表面常常由于環(huán)境介質(zhì)的作用產(chǎn)生大量積垢,覆蓋在設(shè)備表面,嚴(yán)重影響設(shè)備的工作效率,造成極大能源浪費(fèi)和產(chǎn)能下降等經(jīng)濟(jì)損失。這些積垢的最好去除方法是采用化學(xué)清洗,而最常用清洗劑是鹽酸。金屬鋅性質(zhì)活潑,具有極低的標(biāo)準(zhǔn)電極電位,極高的酸反應(yīng)平衡常數(shù),很容易和酸發(fā)生化學(xué)反應(yīng)。因此,清洗積垢時(shí)添加有效緩蝕劑便成了清洗技術(shù)的關(guān)鍵。目前,國內(nèi)外對鋅緩蝕劑的報(bào)道很少,現(xiàn)有鹽酸介質(zhì)中鋅的緩蝕劑都存在各種缺陷,而實(shí)際應(yīng)用中,鹽酸緩蝕劑的需求卻越來越多。因此,鹽酸介質(zhì)中鋅緩蝕劑的開發(fā)研制具有非常重要實(shí)用價(jià)值。本文利用失重法,對數(shù)百種化合物進(jìn)行篩選,選出在鹽酸介質(zhì)中對金屬鋅有良好緩蝕效果的化合物,以方便制備復(fù)合緩蝕劑時(shí)參考使用。從篩選出的化合物中選出緩蝕效果相對較好的水楊醛進(jìn)行了單組份緩蝕劑熱力學(xué)性能研究。研究發(fā)現(xiàn),水楊醛的熱力學(xué)吸附符合朗繆爾吸附規(guī)律。且焓變、熵變、自由能變均小于零,即該緩蝕劑在金屬表面的吸附是混亂度減小的放熱自發(fā)過程。但是,在高溫狀態(tài)下,自由能增大,導(dǎo)致腐蝕速率增大。利用單組份篩選出來的緩蝕劑,經(jīng)過數(shù)千次緩蝕組分的兩兩協(xié)同,三組分協(xié)同及多組分復(fù)配,研制出三種具有非常好的緩蝕效果的復(fù)合緩蝕劑。采用正交試驗(yàn)法,確定他們各自組分之間的最佳比例,最終成功研制出三種新型鹽酸介質(zhì)中金屬鋅緩蝕劑JZA-1、JZA-2和JZA-3。采用失重法研究了三種緩蝕劑的緩蝕性能和對酸度、溫度及時(shí)間的抗干擾能力。研究表明,這三種緩蝕劑具有優(yōu)良的緩蝕性能,尤其是緩蝕劑JZA-1和JZA-2,常規(guī)清洗條件下可使鍍鋅層的腐蝕速率下降至0.2 g·m-2·h-1以下,且不產(chǎn)生非均勻腐蝕現(xiàn)象。緩蝕劑抗干擾能力都很強(qiáng),甚至在酸度達(dá)到10%,或者溫度達(dá)到60℃時(shí),仍未發(fā)現(xiàn)緩蝕劑失效現(xiàn)象;并且時(shí)間越久,緩蝕劑的鋅腐蝕速率越低。通過對三種緩蝕劑進(jìn)行電化學(xué)研究發(fā)現(xiàn),與未加緩蝕劑時(shí)對比,添加緩蝕劑時(shí)使鋅的腐蝕電流明顯減小。JZA-1為電化學(xué)混合抑制型緩蝕劑,而JZA-2、JZA-3為陽極抑制型緩蝕劑。
[Abstract]:Galvanizing equipment has good anticorrosion in atmospheric environment and water quality environment. It has been widely used in food, chemical, petroleum and other industries, such as equipment coating and anode protection, especially in aquaculture cold storage equipment. Food processing industry evaporative condenser equipment, etc. However, in practical application, the surface of galvanizing equipment often produces a large amount of scale due to the action of environmental media, which seriously affects the working efficiency of the equipment and results in great economic losses such as energy waste and the decline of production capacity. The best way to remove these deposits is to use chemical cleaning, and the most commonly used cleaning agent is hydrochloric acid. Zinc has a very low standard electrode potential and a very high equilibrium constant of acid reaction, which makes it easy to react with acid. Therefore, the addition of effective corrosion inhibitor is the key of cleaning technology. At present, there are few reports on zinc corrosion inhibitors at home and abroad. There are various defects in zinc corrosion inhibitors in the existing hydrochloric acid medium, but in practical application, the demand for hydrochloric acid corrosion inhibitors is increasing. Therefore, the development of zinc corrosion inhibitor in hydrochloric acid medium has very important practical value. In this paper, hundreds of compounds were screened by weightlessness method, and the compounds with good corrosion inhibition effect to zinc metal in hydrochloric acid medium were selected, so as to facilitate the preparation of complex corrosion inhibitor. The thermodynamic properties of a single component corrosion inhibitor, salicylic aldehyde, which is relatively good in corrosion inhibition, were selected from the selected compounds. It is found that the thermodynamic adsorption of salicylaldehyde accords with Langmuir adsorption law. The enthalpy change, entropy change and free energy change are all less than zero, that is, the adsorption of the inhibitor on the metal surface is an exothermic spontaneous process in which the degree of confusion decreases. However, at high temperature, the free energy increases and the corrosion rate increases. Three kinds of complex corrosion inhibitors with very good corrosion inhibition effect were developed by using the single component selected corrosion inhibitor after several thousand times of pairwise cooperation of the corrosion inhibitor and the combination of the three components and the multicomponent. The optimum proportion of their components was determined by orthogonal test. Finally, three new metal zinc corrosion inhibitors, JZA-1,JZA-2 and JZA-3., were successfully developed in hydrochloric acid medium. The corrosion inhibition performance of three kinds of corrosion inhibitors and their anti-interference ability to acidity, temperature and time were studied by weightlessness method. The results show that these three inhibitors have excellent corrosion inhibition performance, especially the corrosion rate of zinc coating can be reduced to less than 0.2 g m-2 h-1 under the conditions of JZA-1 and JZA-2,. And does not produce the inhomogeneous corrosion phenomenon. The anti-interference ability of the inhibitor is very strong, even when the acidity reaches 10% or the temperature reaches 60 鈩，

本文編號：2400232