Efficient Adsorption and Mechanism of Organic Dyes on Freeze‐Dried Graphene

Abstract

Organic dyes are widely existing in the waste of printing and dyeing industry, which cannot be ignored due to their potential threats to human health and the environment. Development a useful and simple technology to prepare high‐performance adsorbent to purify the dyes from the wastewater is always a challenging. In this work, the freeze‐drying graphene (FG) is prepared through freeze‐drying process method. In addition, the structural and chemical characteristics between the FG and graphene were comparatively analyzed. The results show that compare to the reference graphene, the FG is a high‐efficiency adsorbent. The theoretical maximum undertakes of rhodamine B and methyl blue were 358.62 and 547.81 mg g−1. The influence and mechanism of affecting factors were investigated, such as contact time, adsorbent dosage, pH, and temperature, to the adsorption. The results suggested that the adsorption of organic dyes on FG followed a homogeneous monolayer physical adsorption (HMPA) mechanism, and the adsorption rates were related to the number of unoccupied vacancies on the adsorbent surface. The characterization instruments of FTIR, XPS, and SEM‐EDS confirmed that the HMPA contains the formation of hydrogen‐bond and π–π interactions, electrostatic attraction, physical pore filling, and complexing adsorption. Our work, proposes a freeze‐drying graphene that is a promising candidate as high‐performance adsorbent to purify the dyes from the wastewater.

Preparation and visible light catalytic degradation of hollow urchin-like TiO2/N-GQDs composites on waste organic dyes

“…With the development of printing and dyeing industry, a large number of pollutants such as organic dyes have been discharged into freshwater resources, which damaged the ecological environment seriously (Jia et al 2023;Chen et al 2021). The organic dyes in printing and dyeing wastewater are di cult to achieve direct degradation because of their stable properties, high chroma and complex structure, which is an urgent water pollution problem (Saghir et al 2021;Hu et al 2019).…”