Extraction of eco-friendly and biodegradable surfactant for inhibition of copper corrosion during acid pickling

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

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Root Cause Analyses of Metal Bridging for Copper Damascene Process

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0283 ◽

2005 ◽

Author(s):

Z. G. Song ◽

S. P. Neo ◽

S. K. Loh ◽

C. K. Oh

Keyword(s):

Failure Mechanisms ◽

Copper Corrosion ◽

Microelectronic Device ◽

Root Cause ◽

Damascene Process ◽

New Process ◽

Copper Cmp

Abstract New process will introduce new failure mechanisms during microelectronic device manufacturing. Even if the same defect, its root causes can be different for different processes. For aluminum(Al)-tungsten(W) metallization, the root cause of metal bridging is quite simple and mostly it is blocked etch or under-etch. But, for copper damascene process, the root causes of metal bridging are complicated. This paper has discussed the various root causes of metal bridging for copper damascene process, such as those related to litho-etch issue, copper CMP issue, copper corrosion issue and so on.

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Aerospace series - Acid pickling of aluminium and aluminium alloys without hexavalent chromium

10.3403/30389712 ◽

2020 ◽

Keyword(s):

Hexavalent Chromium ◽

Aluminium Alloys ◽

Acid Pickling

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Water treatment to reduce internal corrosion in the drinking water distribution system in Oslo

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0056 ◽

2001 ◽

Vol 1 (3) ◽

pp. 91-96 ◽

Cited By ~ 1

Author(s):

L.J. Hem ◽

E.A. Vik ◽

A. Bjørnson-Langen

Keyword(s):

Water Treatment ◽

Corrosion Rate ◽

Distribution System ◽

Water Distribution ◽

Treatment Plant ◽

Water Treatment Plant ◽

Corrosion Monitoring ◽

Copper Corrosion ◽

Iron Corrosion ◽

Internal Corrosion

In 1995 the new Skullerud water treatment plant was put into operation. The new water treatment includes colour removal and corrosion control with an increase of pH, alkalinity and calcium concentration in addition to the old treatment, which included straining and chlorination only. Comparative measurements of internal corrosion were conducted before and after the installation of the new treatment plant. The effect of the new water treatment on the internal corrosion was approximately a 20% reduction in iron corrosion and a 70% reduction in copper corrosion. The heavy metals content in standing water was reduced by approximately 90%. A separate internal corrosion monitoring programme was conducted, studying the effects of other water qualities on the internal corrosion rate. Corrosion coupons were exposed to the different water qualities for nine months. The results showed that the best protection of iron was achieved with water supersaturated with calcium carbonate. Neither a high content of free carbon dioxide or the use of the corrosion inhibitor sodium silicate significantly reduced the iron corrosion rate compared to the present treated water quality. The copper corrosion rate was mainly related to the pH in the water.

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Characterization of Phosphate Coatings: Influence of the Acid Pickling Conditions

Materials ◽

10.3390/ma14041048 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1048

Author(s):

Belén Díaz ◽

X. Ramón Nóvoa ◽

Carmen Pérez ◽

Sheila Silva-Fernández

Keyword(s):

Citric Acid ◽

High Strength ◽

Acid Pickling ◽

Acid Cleaning ◽

Inorganic Acids ◽

Phosphate Coatings ◽

Acid Bath ◽

Coating Morphology ◽

Coating Weight

This research emphasizes the importance of the acid cleaning prior to the phosphate development on high-strength steel rods. It compares the phosphate properties achieved after different acid-pickling conditions. The most common inorganic acids were considered in this study. Additionally, taking into account the environmental and safety concerns of these acids, the assessment of a less harmful organic acid is presented. This study revealed significant differences in the coating morphology and chemical composition whereas no great changes were found in terms of the coating weight or porosity. Thus, hydrochloric and sulfuric acid promote the growth of a Fe-enriched phosphate layer with a less conductive character that is not developed after the pickling with phosphoric acid. The phosphate developed after the citric acid pickling is comparable to that developed after the inorganic acids although with a porosity slightly higher. The temperature of the citric acid bath is an important parameter that affects to the phosphate appearance, composition, and porosity.

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Preparation, Characterization, and Evaluation of Macrocrystalline and Nanocrystalline Cellulose as Potential Corrosion Inhibitors for SS316 Alloy during Acid Pickling Process: Experimental and Computational Methods

Polymers ◽

10.3390/polym13142275 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2275

Author(s):

Arafat Toghan ◽

Mohamed Gouda ◽

Kamal Shalabi ◽

Hany M. Abd El-Lateef

Keyword(s):

Surface Area ◽

Density Functional ◽

Protective Efficacy ◽

Protective Layer ◽

Nanocrystalline Cellulose ◽

Bet Surface Area ◽

Natural Polymers ◽

Active Centers ◽

Acid Pickling ◽

Pickling Process

Converting low-cost bio-plant residuals into high-value reusable nanomaterials such as microcrystalline cellulose is an important technological and environmental challenge. In this report, nanocrystalline cellulose (NCC) was prepared by acid hydrolysis of macrocrystalline cellulose (CEL). The newly synthesized nanomaterials were fully characterized using spectroscopic and microscopic techniques including FE-SEM, FT-IR, TEM, Raman spectroscopy, and BET surface area. Morphological portrayal showed the rod-shaped structure for NCC with an average diameter of 10–25 nm in thickness as well as length 100–200 nm. The BET surface area of pure CEL and NCC was found to be 10.41 and 27 m2/g, respectively. The comparative protection capacity of natural polymers CEL and NCC towards improving the SS316 alloy corrosion resistance has been assessed during the acid pickling process by electrochemical (OCP, PDP, and EIS), and weight loss (WL) measurements. The outcomes attained from the various empirical methods were matched and exhibited that the protective efficacy of these polymers augmented with the upsurge in dose in this order CEL (93.1%) < NCC (96.3%). The examined polymers display mixed-corrosion inhibition type features by hindering the active centers on the metal interface, and their adsorption followed the Langmuir isotherm model. Surface morphology analyses by SEM reinforced the adsorption of polymers on the metal substrate. The Density Functional Theory (DFT) parameters were intended and exhibited the anti-corrosive characteristics of CEL and NCC polymers. A Monte Carlo (MC) simulation study revealed that CEL and NCC polymers are resolutely adsorbed on the SS316 alloy surface and forming a powerful adsorbed protective layer.

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