A novel silica xerogel synthesized from volcanic tuff as an adsorbent for high‐efficient removal of methylene blue: parameter optimization using Taguchi experimental design

Abstract

BACKGROUND: In this study, silica xerogel was synthesized using volcanic tuff instead of expensive silica precursors at ambient pressure drying. The mesoporous silica xerogel with unique structural and textural properties was evaluated as an adsorbent for methylene blue (MB) removal from aqueous solution. Taguchi method was applied to optimize controllable factors (contact time, initial MB concentration, silica xerogel dose, temperature and pH) for MB removal. RESULTS:The temperature was determined as the most significant factor with percentage contribution of 54.50%. MB removal efficiency was 96.18% at optimum conditions (contact time: 60 min, initial MB concentration: 20 ppm, silica xerogel dose: 0.0016 g mL −1 , temperature: 40 ∘ C, pH: 5). The experimental data fitted with the Langmuir isotherm, yielding a maximum adsorption capacity of 51.967 mg g −1 . MB desorption process was performed depending on eluent concentration and contact time. Maximum desorption efficiency was specified as 88% using 1 M hydrochloric acid for 4 h. The silica xerogel was easily recycled with retaining approximately 70% of adsorption efficiency after five cycles. CONCLUSION: In the light of the promising results, the silica xerogel can be used as an effective adsorbent in many environmental applications. MB desorption process and reusabilityThe simple regeneration and reusability of adsorbent are important factors in adsorption processes in terms of economy. Desorption efficiency of MB adsorbed silica xerogel depending on HCl concentration and contact time is shown in Fig. 5. Desorption

Transformation of Glass Fiber Waste into Mesoporous Zeolite-Like Nanomaterials with Efficient Adsorption of Methylene Blue

“…Table 3 shows a comparison of the adsorption capacity of MB by MZN with the reported data obtained from the various silica-based adsorbents. The reported adsorption capacity for MB by a wide variety of silica-based adsorbents, including PVDF/glass asprepared composite membrane [49], silica xerogel [27], pure silica [50], hollow silica [51], Ag/SiO 2 [52], and hydroxyl group silica aerogel [53], were in the range of 44.4-102 mg g −1 , respectively. In this study, the adsorption capacity of MB by MZN is better than most of the reported silica-based adsorbents, indicating that MZN is an excellent negative charged material for effective adsorption of positive charged MB in an aqueous solution.…”

“…A Taguchi optimization study like this should reduce energy consumption in resource-related industries. Several studies have been conducted to investigate the optimum process parameters to enhance adsorption capacity to remove methylene blue [27] and optimize Pb(II) ion adsorption on nanohydroxyapatite adsorbents [28]. However, different parameters (reaction agent ratio, temperature, time, and agent concertation) significantly affect the quality of the material process, which affects the efficiency of organic dye removal.…”

Antibacterial Activity of Linezolid against Gram-Negative Bacteria: Utilization of ε-Poly-l-Lysine Capped Silica Xerogel as an Activating Carrier

“…Synthesis procedure of silica xerogel consisted of three steps after pretreatment of the volcanic tuff [ 37 ]. The tuff was washed with 3 M HCl solution for 2 h at 60 °C to eliminate undesirable minerals.…”

EXPLORING MIL-53 (Al) ADSORPTION EFFICIENCY FOR INDIGO CARMINE DYE

“…As depicted in the figure, the pHpzc value for MIL-53 (Al) was calculated as 4.1. If the pH of the medium is below 4.1, the net adsorbent charge is positive, while above it is negative [24]. In this case, at the optimum pH value (pH=3.2) the adsorbent charge is positive.…”