Navarro Patricia, Zapata Jean Pier, Gotor Gemma, Gonzalez-Olmos Rafael, Gómez-López Vicente M
Departamento de Ciencia y Tecnología de Alimentos, Universidad Católica de Murcia (UCAM), Campus de los Jerónimos 135, Guadalupe, 30107 Murcia, Spain.
IQS School of Engineering, Universitat Ramon Llull, Via Augusta 390, 08017 Barcelona, Spain.
Water Sci Technol. 2019 Jan;79(2):260-269. doi: 10.2166/wst.2019.041.
Pulsed light (PL) is a type of photonic technology characterized by intense short light pulses that enhance the speed of photochemical reactions, and which might be useful as light source in advanced oxidation processes. This work aimed to test PL as light source for the degradation of the dye malachite green (MG) by combining PL with HO. To this end, the effect of dye and HO concentrations and pH on the degradation rate of MG was studied and a degradation pathway was proposed. Dye degradation followed a pseudo-first order kinetics; it increased with low initial dye concentration, high HO concentration and low pH. Complete decolourization was achieved after 35 light pulses (75 J/cm), with a degradation rate of 0.0710 cm/J. The degradation was initiated by the attack of hydroxyl radicals to the central carbon of MG generating 4-(dimethylamino)benzophenone (DLBP) followed by the addition of hydroxyl radicals to the non-amino aromatic ring of DLBP and the demethylation of the amino group. Results indicate that PL technology has potential to be implemented to decrease the environmental impact of dyeing industries.
脉冲光（PL）是一种光子技术，其特点是具有强烈的短光脉冲，可提高光化学反应速度，并且在高级氧化过程中可能用作光源。这项工作旨在通过将脉冲光与羟基自由基（HO）结合，测试其作为降解染料孔雀石绿（MG）的光源。为此，研究了染料浓度、羟基自由基浓度和pH值对孔雀石绿降解速率的影响，并提出了降解途径。染料降解遵循准一级动力学；降解速率随初始染料浓度低、羟基自由基浓度高和pH值低而增加。在35个光脉冲（75 J/cm²）后实现了完全脱色，降解速率为0.0710 cm²/J。降解过程始于羟基自由基攻击孔雀石绿的中心碳原子生成4-（二甲基氨基）二苯甲酮（DLBP），随后羟基自由基加成到DLBP的非氨基芳香环上并使氨基脱甲基。结果表明，脉冲光技术有潜力用于减少印染行业对环境的影响。
