Printing and dyeing wastewater is known for its complex composition, high volume, intense color, and elevated COD levels. It often contains rayon saponification products and various new chemical additives, which introduce a large number of refractory organic compounds into the water. This makes the wastewater resistant to both oxidation and biological degradation, posing significant challenges in treatment. Eliminating high color intensity and high COD values has long been a critical issue in the treatment of printing and dyeing wastewater [1]. Currently, most domestic and international approaches rely on biochemical methods with chemical support, but these techniques suffer from high operational costs, limited effectiveness, and difficulties in removing color and COD. Semiconductor photocatalytic oxidation technology is emerging as a promising solution due to its low energy consumption, ease of operation, and lack of secondary pollution. Among photocatalysts, nano-TiO2 (TiO₂) is the most widely used, and its application in treating printing and dyeing wastewater holds considerable theoretical and practical value [2–3]. However, most studies on photocatalytic degradation focus on small organic molecules, while the degradation of macromolecular organic matter using nano-TiO2 has not been well documented. In this study, actual printing and dyeing wastewater was treated using a quartz sand film loaded with nano-TiO2, and the reaction kinetics were investigated.
Experimental Procedure 1.1 Main Equipment and Reagents A medical ultraviolet lamp (30W), a homemade photocatalytic reactor (a rectangular groove made of mirror glass, measuring 50mm × 15mm × 5mm), quartz sand (particle size: 7–10mm), ammonium fluorotitanate, HCl, anhydrous ethanol, and other reagents were used. All reagents were of analytical grade. 1.2 Experiment 1.2.1 Preparation of Nano-TiO₂ Film-Loaded Quartz Sand In this experiment, a nano-TiO₂ film-loaded quartz sand was prepared using a liquid deposition method. Ammonium fluorotitanate and boric acid were used as precursors. They were dissolved separately and mixed uniformly to form an aqueous solution with concentrations of C(NH₄)₂Ti₂F₆ = 0.1 mol/L and CH₃BO₃ = 0.3 mol/L. 100 g of pre-washed quartz sand, cleaned with deionized water, HCl, NaOH, and absolute ethanol, was placed in a beaker. Then, 250 mL of the ammonium fluorotitanate-boric acid mixture was added. The beaker was covered with a watch glass and kept at a constant temperature in a water bath at 40°C for 50 hours. Afterward, the TiO₂-coated quartz sand was removed, washed, air-dried, and heat-treated in a muffle furnace at 450°C for 30 minutes. Finally, it was stored away from light for further use.
Company hot products: steamer _ steaming machine _ steaming box _ steaming pot _ steaming machine
Company website:
Solid Rivets, Steel Solid Rivets, Solid Aluminum Rivets, Flat Head Solid Rivets
Ningbo Brightfast Machinery Industry Trade Co.,Ltd , https://www.brightfastener.com