The escalation of industrial operations has heightened alarm regarding the announcement of toxic heavy metals interested in natural aquatic systems. Lead (II) stands out as particularly dangerous because of its longevity in the environment and its adverse repercussions on both human and ecological health [1]. Contact with Pb(II) can cause a range of health issues, underscoring the urgent need for the creation of effective removal technologies to alleviate its detrimental effects [2]. Adsorption has gained recognition as a highly effective method for the remediation of heavy metals, primarily attributed to its straightforward implementation, effectiveness, and economic viability. Numerous adsorbents have been investigated, encompassing conventional materials like activated carbon and more sophisticated frameworks like metal–organic frameworks (MOFs). MOFs are crystalline substances made through the coordination of metal ions with organic compounds [3]. Their distinctive properties including adjustable pore architectures, considerable surface areas, and customizable surface chemistries render them particularly suitable for applications involving adsorption [4]. Vanadium-based metal-organic frameworks (V-MOFs) constitute a recently developed subgroup of metal-organic frameworks (MOFs). The unique redox-active properties of vanadium confer additional functionalities to these frameworks, which may improve their interaction with metal ions during the adsorption process. Nevertheless, the fundamental weakness of MOFs, combined with their instability in aqueous environments, frequently restricts their application as standalone materials [3].

To address the identified limitations, researchers have incorporated metal-organic frameworks (MOFs) into biodegradable polymeric matrices, thereby enhancing their stability and operational efficacy. A notable strategy in this domain involves the encapsulation of V-MOF within a hybrid matrix composed of carboxymethyl cellulose (CMC) and polyethylenimine (PEI), which is crosslinked via epichlorohydrin [5]. This resultant composite, referred to as VMCP, integrates the structural advantages of the MOF while leveraging the hydrophilic characteristics and functional groups of the biopolymers [6]. Consequently, this results in improved adsorption capabilities and greater mechanical strength. The strategy aligns with current trends in sustainable material development, highlighting the growing focus on biopolymer-MOF composites for environmental remediation purposes. Research into similar composites, particularly VMAC (which combines vanadium MOF, alginate, and chitosan), has shown improved performance attributable to the synergistic interactions between metal-organic frameworks and usual polymers. Such findings substantiate the promise of MOF-based hybrid adsorbents as effective approaches to tackling issues associated with water pollution [7].

The development and utilization of metal-organic framework (MOF) composites have advanced markedly in recent years. Scholars are progressively harnessing the adjustable properties of MOFs in conjunction with the processability and environmental friendliness of biopolymers to fabricate sophisticated materials specifically designed for water purification applications [8]. These composite systems offer significant benefits as they integrate various mechanisms for the elimination of contaminants, such as surface adsorption, ion exchange, and complexation facilitated by functional groups. A significant issue linked to metal-organic frameworks (MOFs) is their susceptibility to hydrolysis and potential structural degradation in water-based environments [9]. The encapsulation of MOFs within polymeric matrices offers a viable approach to address these challenges. Polymers like carboxymethyl cellulose (CMC) and carboxymethyl cellulose are commonly utilized due to their biodegradable nature, affinity for water, and presence of reactive sites including hydroxyl and amino groups. Notably, polyethylenimine (PEI) is extensively applied to incorporate nitrogen functionalities, which improve the coordination and adsorption efficiency of metal ions. Notably, polyethylenimine (PEI) is extensively applied to incorporate nitrogen functionalities, which improve the coordination and adsorption efficiency of metal ions [10].

VMAC composites, comprising vanadium-based metal-organic frameworks (MOFs) alongside carboxy methyl cellulose and polyethylenimine, represent an innovative class of hybrid adsorbents. The incorporation of alginate is beneficial because of its excellent film formation properties and ion exchange capabilities. Additionally, chitosan enhances the composite by adding amino groups that facilitate electrostatic interactions and chemical bonds. On the other hand, carboxymethyl cellulose (CMC) enhances adsorption efficiency due to its hydrophilic nature and a high concentration of hydroxyl and carboxyl groups, providing additional active sites for interaction with contaminants [11]. Utilizing these biopolymers results in frameworks that are both economically and environmentally sustainable, which makes them very useful for treating wastewater in resource-constrained environments. Additionally, the integration of vanadium as a central metal in the MOF synthesis process brings distinct benefits [12]. Vanadium ions are capable of engaging in redox reactions, which may enhance mechanisms for the degradation or binding of contaminants. Furthermore, vanadium's ability to form stable complexes with multidentate ligands facilitates the development of resilient MOF structures characterized by high surface area and porosity key attributes that significantly improve adsorption efficiency [13].

The analysis of MOF-polymer composites is essential for comprehending their functional efficacy. Numerous characterization approaches, including XRD, SEM, FT-IR, and nitrogen adsorption–desorption analysis are working to clarify the fundamental, chemical, as well as surface appearances of these materials. Such analytical techniques validate the effective synthesis of the composite, identify functional groups, and confirm the mesoporous structure that is critical for effective adsorption processes [14]. Beyond structural analysis, it is imperative to investigate the adsorption characteristics of the composite through carefully designed batch experiments. These investigations involve measuring the properties of variables like pH, temperature, contact period, and adsorbent quantity on the efficiency of removal. Gaining insights into these factors improves our empathetic of the adsorption device and aids in the optimization of settings for practical requests in real-world scenarios [15].

The amalgamation of Metal-Organic Frameworks (MOFs) with biopolymers is indicative of the prevailing global trend toward the development of sustainable materials aimed at reducing ecological footprints while enhancing functional efficacy [16]. These environmentally friendly adsorbents represent a viable approach for advancing water purification technologies, particularly as international regulations surrounding allowable concentrations of heavy metals in industrial wastewater become increasingly stringent [17]. The adaptability and potential for reuse of these composite materials further bolster their attractiveness for wide-ranging application. This investigation makes a noteworthy influence to the discipline of environmental nanotechnology by delivering an in-depth analysis of a novel composite based on V-MOF for the extraction of lead. It effectively merges core principles of material science with the practical applications of environmental engineering to tackle an urgent environmental challenge. The innovative architecture, comprehensive characterization, and detailed assessment of the adsorbent underscore its promise as a scalable intervention for heavy metal contamination across various aquatic ecosystems [18].

In addition, the utilization of statistical methodologies, exemplified by the Box–Behnken design, is becoming more prevalent in the modeling and optimization of adsorption procedures. Such designs allow for an in-depth exploration of variable interactions, assessment of their importance, and identification of ideal settings to achieve peak efficacy [19]. The integration of statistical modeling not only bolsters the validity of the results but also aids in the effective application of laboratory-scale findings to industrial contexts [20].

This study presents a significant innovation through the formulation and integration of a vanadium-based metal-organic framework (V-MOF) within a dual biopolymer matrix comprised of carboxymethyl cellulose (CMC) and polyethylenimine (PEI). The result is a new composite adsorbent (VMCP) specifically designed to effectively remove Pb(II) ions from wastewater. This approach differs from traditional adsorbents by uniquely combining the strong attraction of V-MOF for heavy metal ions with the abundance of functional groups present in biopolymers. Further stabilization is achieved through epichlorohydrin crosslinking, which enhances both structural integrity and adsorption capabilities. The VMCP composite features a mesoporous architecture considered by a high specific surface area and accessible pores, contributing to an impressive high adsorption capacity. Notably, this research incorporates Box-Behnken design optimization to fine-tune and accurately assess the operational parameters of the biopolymer-MOF hybrid system. The composite also demonstrates remarkable recyclability across multiple adsorption-desorption cycles, maintaining performance with minimal degradation, underscoring its practical application potential. This integrated methodology offers a sustainable, economical, and high-efficiency solution for addressing heavy metal contamination in water systems, representing a substantial progress in the technology of MOF-biopolymer hybrid adsorbents.