Vol.:(0123456789) 1 3 Carbon Letters https://doi.org/10.1007/s42823-020-00185-3 ORIGINAL ARTICLE Synthesis and characterization activated carbon using a mix (asphalt‑polypropylene waste) for novel azo dye (HNDA) adsorption Homam T. S. AL‑Sayd Toohi 1  · Muwafaq Ayesh Rabeea 2  · Jasim Ali Abdullah 3  · Rasim Farraj Muslim 4 Received: 11 March 2020 / Revised: 14 June 2020 / Accepted: 7 September 2020 © Korean Carbon Society 2020 Abstract This work reveals a modifed method for the preparation of activated carbon (P-ACA) using low-cost materials (mix natural asphalt: polypropylene waste). The P-ACA was prepared at 600 °C by assisting KOH and HF. The morphological varia- tions and chemical species of the P-ACA were characterized using SEM–EDX and FTIR. The active surface area, density and ash content of the P-ACA were also investigated. Adsorption properties of P-ACA were used for the thermodynamic and kinetic study of 4-((2-hydroxy naphthalenyl) diazenyl) antipyrine (HNDA), which was prepared as a novel azo dye in this work. The optimal conditions (initial concentration, adsorbent dose, contact time and temperature) of the adsorption process were determined. Adsorption isotherms (Freundlich and Langmuir) were applied to the experimental data. These isothermal constants were used to describe the nature of the adsorption system, and the type of interaction between the dye and the P-ACA surface. The results have indicated that the mixture (Natural asphalt-polypropylene waste) is efcient for the synthesis of P-ACA. The synthesized P-ACA demonstrates the presence of pores on the surface with various diameter ranges (from 1.4 to 4.5 μm). Furthermore, P-ACA exhibits an active surface area of 1230 m 2  g −1 , and shows a high adsorp- tion capacity for HNDA. Keywords Activated carbon · Adsorption · Antipyrine azo dyes · Thermodynamic study · Waste polypropylene 1 Introduction Pollution is a hazardous and difcult issue that currently confronts the world resulting from industrial revolutions. This has raised pollution to higher levels than the normal standard, thus creating an imbalance in the environment and increasing the risk level of pollution. This level of pollu- tion has necessitated the need for substantial treatment and amelioration techniques [1–3]. Water pollution is the most hazardous type of pollution since it plays a crucial role in the lifecycle; hence, it is a fundamental component in a variety of related studies. Azo dyes are one of the largest groups of dyes which are extensively synthesized and utilized in numerous industries due to their high stability and several unique colors. However, most azo dyes are toxic and harmful to human health, which they should be treated before being released to the environment [4–7]. Several approaches have been employed for the removal of these dyes from wastewa- ter, but they are negated by their high costs and toxic efects. Adsorption is a technique used conventionally to remove the dye. It is cost-efective and entails a simple procedure [8–11]. Activated carbon is extensively utilized as dyes sorb- ent, although its potential wide application is hindered by its high cost. Hence, there is a need to produce cost-efective activated carbon with accessible raw materials [12–16]. Asphalt is extracted industrially from the non-destructive distillation of crude oil; sometimes it emerges naturally as heavy oil on the surface of the earth [17]. Asphalt is a mix- ture of hydrocarbons (aliphatic and aromatic compounds) and has a small amount of heteroatoms in its backbone [18]. The addition of polymer to the high shear blender results in the dispersion of polymer pellets into the fne particles and, hence, the polymer surface is larger in the continuum asphalt Online ISSN 2233-4998 Print ISSN 1976-4251 * Muwafaq Ayesh Rabeea muw88@uoanbar.edu.iq 1 Department of Medical Laboratory Technique, Al-Hadba’a University College, Mosul, Iraq 2 Department of Applied Chemistry, College of Applied Sciences-Hit, University Of Anbar, Anbar 31001, Iraq 3 Department of Chemistry, College of Education for Pure and Science, University of Mosul, Mosul, Iraq 4 Department of Environmental Sciences, College of Applied Sciences-Hit, University Of Anbar, Anbar, Iraq