Comparison of monochloramination and chlorination of 1,3-diphenylguandine (DPG): Kinetics, transformation products, and cell-based in-vitro testing.

As a widely used secondary vulcanization accelerator in the rubber industry, 1,3-diphenylguanidine (DPG) poses risks to human health and the environment. To compare and comprehend the disinfection process of DPG, this work investigates the reaction kinetics, toxicity, and transformation products (TPs) of DPG during chlorination and monochloramination. It has been revealed that the reactivity of monochloramine is significantly slower compared to chlorination of DPG, with the maximum efficiency observed at pH 7 to pH 8.

Reactions of Monobromamine and Dibromamine with Phenolic Compounds and Organic Matter: Kinetics and Formation of Bromophenols and Bromoform.

Monobromamine (NHBr) and dibromamine (NHBr) produced from reactions of hypobromous acid (HOBr) with ammonia can react with phenolic structures of natural organic matter (NOM) to produce disinfection byproducts such as bromoform (CHBr). The reactivity of NHBr was controlled by the reaction of the bromoammonium ion (NHBr) with phenolate species, with specific rate constants ranging from 6.32 × 10 for 2,4,6-tribromophenol to 1.

Kinetic modelling of the bromine-ammonia system: Formation and decomposition of bromamines.

Bromamines i.e. monobromamine (NHBr), dibromamine (NHBr), and tribromamine (NBr) can be formed during oxidative treatment of waters containing bromide and ammonia.

Brominated trihalamines in chlorinated seawaters: Quantification of tribromamine and identification of bromochloramines by Membrane Introduction Mass Spectrometry.

During chlorination of seawater, the presence of bromide and ammonia alters the speciation of the oxidant and lead to the formation of chlorinated and brominated amines. This can affect the effectiveness of the disinfection treatment and the formation of disinfection by-products released to the environment. In this study, a Membrane Introduction Mass Spectrometry (MIMS) analytical method was developed to differentiate brominated trihalamines (i.