Cleaner Engineering and Technology 3 (2021) 100119 Available online 18 May 2021 2666-7908/© 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Biomass-mediated synthesis of silver nanoparticles composite and application as green corrosion inhibitor in oilfeld acidic cleaning fuid Ekemini Ituen a, b, c, * , Ambrish Singh a, b , Lin Yuanhua a, b, ** , Onyewuchi Akaranta d a State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, Sichuan, China b School of Materials Science and Engineering, Southwest Petroleum University, Chengdu, 610500, Sichuan, China c Emerging Materials and Energy Research Group, Department of Chemistry, University of Uyo, Uyo, Nigeria d African Center of Excellence in Oilfeld Chemicals Research, Institute of Petroleum Studies, University of Port Harcourt, Nigeria A R T I C L E INFO Keywords: Nanoscale characterization Nanocomposites Corrosion inhibitor AFM XRD TEM ABSTRACT Aqueous extract of red onion peels mediates the synthesis of silver nanoparticles composite (AqAgNPs). The AqAgNPs were characterized using X-ray diffraction, microscopic and spectroscopic techniques and evaluated as anticorrosion additive for pipeline (X80) steel. Spherical, stable, crystalline, monodisperse and non-agglomerated particles of 50 nm average size were obtained. In laboratory simulated acidic cleaning solution (1 M HCl), AqAgNPs exhibits impressive anticorrosion effect on X80 steel surface even at small concentrations (25% v/v) at 30–60 ◦ C as determined by weight loss and electrochemical techniques. AqAgNPs is thermally and biochemically stable and still affords 86% effciency at 60 ◦ C even after 120 days of storage. FTIR and EDS studies reveal that AqAgNPs species interact with steel surface by adsorption using mainly by O and N sites. Microscopic (SEM and AFM) examination of the steel surface reveals suffcient protection and reduction in pitting by 70.5%. Instead of being discarded as waste, onion peels could be processed into oilfeld chemicals as demonstrated in this study. 1. Introduction Many classes of chemicals are usually deployed in oil and gas pro- duction and these chemicals are referred to as oilfeld chemicals. Some examples of oilfeld chemicals include drilling mud additives, sulphur scavengers, oil-water clarifers in enhanced oil recovery (EOR) waste water, surfactants, biocides, scale inhibitors, wax control agents, anti- fouling agents, gas hydrates inhibitors, anti-foaming agents, emulsion breakers and corrosion inhibitors (CIs). Corrosion inhibitors constitute an important class of oilfeld chemicals because corrosion is a crucial problem in oil and gas production. Corrosion occurs almost at every stage of oilfeld operation, from drilling to completions, production, transportation, storage and enhanced oil recovery stages of oilfeld op- erations. Indeed, corrosion is a global challenge in petroleum production. Corrosion of steel materials like line pipes, tubing and casings occurs mainly due to contact of steel with acid, especially hydrochloric acid (HCl) used for acid wash, well stimulation, matrix acidizing and fracturing (Carvalho et al., 2019), (Garrouch and Jennings, 2017). The concentration of HCl commonly used could be up to 5% for pickling, descaling or mild acidizing jobs (Mubarok and Zarrouk, 2017) and 15–25% for stimulation and fracture jobs (Gueccia et al., 2019). How- ever, HCl is very corrosive whatever the concentration used. If not inhibited using corrosion inhibitors, corrosive attack of the acid on steel structural materials could lead to rupturing, spills, materials failure, loss of lives and company integrity, and fow problems. It is therefore crucial to add small proportions of CIs to the acidic fuid before injection and the CIs are believed to work by adsorption on the steel surface, resulting in a protecting or ‘blanketing’ layer on the surface (Ituen et al., 2017), (Obi-Egbedi and Obot, 2013). The adsorption is achieved by physical or chemical interactions between electron rich sites such as S, O, P and N atoms, multiple bonds, heterocyclic and aromatic rings present in the CI with the empty orbitals of iron in the steel surface (Bahlakeh et al., 2017). Several classes of corrosion inhibitors have been developed, tested and found to be effcient in various acidic solutions (Ahmed et al., 2018), * Corresponding author. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, Sichuan, China. ** Corresponding author. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, Sichuan, China. E-mail addresses: ebituen@gmail.com (E. Ituen), yhlin28@163.com (L. Yuanhua). Contents lists available at ScienceDirect Cleaner Engineering and Technology journal homepage: www.sciencedirect.com/journal/cleaner-engineering-and-technology https://doi.org/10.1016/j.clet.2021.100119 Received 24 October 2020; Received in revised form 22 March 2021; Accepted 12 May 2021