## 1 Introduction  
Our previous studies successfully demonstrate a novel nutraceutical industrial spent as a new class of bio-sorbents to amputate dyes from water and industrial effluents. The resultant dye adsorbed waste as a filler material and a plastic waste to fabricate composites [1]. The ever-growing demands for textile products are by far one of the principal supporters of ecological contamination. The insatiable consumption of water in textile industries has also led to a massive water pollution problem as well [2]. This is because, in this industry, in various stages, the discharge waste contains a variety of dyes that poses a technical challenge for the treatment of water and is, of course, a threat to the environment and health of the ecosystem [3]. Accordingly, there is a need to develop innovative, efficient, and cost-effective methods to treat textile industrial effluents. Much effort has been made to utilize different techniques, including but not limited to biological [4], chemical [5], photo-chemical [6], and physical routes [7; 8; 9] Despite some promising results, however, they have three significant deficiencies such as (1) economically unviable, (2) production of undesirable degradation products which display more toxicity than the precursors, and (3) production of undesirable sludge. Adsorption as a mass transfer technique offers a plausible heat transfer coefficient and feasible approach for the remediation of dyes [10]. One of the significant drawbacks of the adsorption techniques, particularly in the remediation of dyes in a textile industrial effluent, is attributed to the production of highly concentrated sludge, which leads to a disposal problem. Initiated carbon has generally been utilized for remediation of colors in the textile industries, which adds to the complexity of the process and the final cost of the products considering the need for regeneration of active carbon [11]. This is the primary driver to seek alternative approaches aiming to treat effluents with more cost-effective and environmentally benign methods. The requirement of the quantity of adsorbent for remediation in a textile industry runs into tons of material. Thus, the process for removing dyes from the effluents obtained from textile industries should be economical and eco-friendly. To satisfy these requirements, clay minerals are most appropriate as adsorbents for the amputation of dyes from effluents. However, clay minerals need to be optimized as nanomaterials to enhance several properties targeted for specific applications [12]. Amongst many nanoclay minerals available in abundance, halloysite nanotube (HNT) finds applications in catalysis [13], cosmetics and pharmacy [14], and medicine [15]. We have selected HNT as a choice of adsorbent to suit the design of the circular economy (CE) concept for two reasons. Firstly, it has a tubular structure with functional groups on the surface and inside the pore with different chemistries, enhancing the efficiency of adsorption during the remediation process of dyes. Secondly, HNT as a reinforcement material has been extensively used to fabricate nanocomposites [16]. Azo dyes are currently banned from use in industrial and domestic sectors all over the world. However, they are being processed to produce up to 70% of dyes used in the textile industry due to their inherent properties, such as (1) simple and cost-effective synthesis in aqueous media, (2) availability of colossal choice of starting materials, (3) a wide spectrum of shades, (4) high intensity and superior fastness of the color, (5) versatility in applications on a variety of substrates and (6) energy-saving dyeing process at 60 \({}^{\circ}\)C when compared to boiling temperature of its counterparts [17]. DB15 is a bis azo dye utilized to dye materials such as cellulose, leather, wool, and paper. The dye is also utilized for staining biological materials and to tint cinematographic films.