The discharge of synthetic dyes into aquatic systems poses serious environmental and public health concerns due to their toxicity, persistence, and resistance to biodegradation. Rosaniline hydrochloride, a cationic triarylmethane dye, is widely used in textiles, leather tanning, and biological laboratories, yet its removal from wastewater remains a major challenge. This study investigated the application of silica gel as an adsorbent for the removal of rosaniline hydrochloride from aqueous solutions under controlled laboratory conditions. A stock solution of 500 mg/L was prepared, and working solutions of varying concentrations were obtained through serial dilution. Batch adsorption experiments were carried out to examine the effect of key operational parameters, including contact time (30-90 min), adsorbent dosage (2-4 g), initial concentration (20-100 mg/L), and temperature (25-80°C). The percentage removal efficiency and adsorption capacity were determined using a UV-Visible spectrophotometer. The results revealed that adsorption efficiency increased with higher contact time and adsorbent dosage, while removal decreased at higher dye concentrations due to surface saturation. Temperature was found to enhance adsorption, with maximum removal efficiency observed at elevated temperatures. These findings demonstrate that silica gel is an effective and low-cost adsorbent for the removal of rosaniline hydrochloride, with potential applicability in small-scale and decentralized wastewater treatment systems.
Umar et al. (Fri,) studied this question.