The acidic bromate oxidation of ferroin in batch reaction proceeds with slow consumption of bromide until a critical bromide concentration is attained. At that point ferroin is suddenly oxidized to ferriin in a process involving autocatalytic generation of bromous acid. Prior to the transition, in an unstirred thin film of solution, a single trigger wave of chemical reactivity may develop and s...

Ozone process has been widely used for drinking water treatment recently. In the oxidation process, bromate is formed by three pathways, i.e., the direct pathway, the direct-indirect pathway and the indirect-direct pathway. This study developed a method to calculate the percentage of these three pathways for bromate formation during O3 process and O3/H2O2 process. Two kinds of water, distilled ...

In cell free extracts of yeast, glycolysis exhibits nonlinear temporal behaviour, in response to the infusion rates of metabolisable sugars. Such bistability in closed systems is difficult. In the closed system, the glycogen induced nonlinear behaviour in cell free extracts of Saccharomyces carlsbergensis are described and the control characteristics are evaluated. In closed chemical systems in...

A novel simple, sensitive and rapid kinetic-spectrophotometric method for the determination of trace amounts of nitrite is proposed. The method is based on its catalytic effect on the oxidation of congo red (CR) by potassium bromate in acidic solution. The oxidation reaction is monitored spectrophotometrically by measuring the decrease in the absorbance of CR at a suitable λmax = 570 nm for the...

Ozonation followed by biological activated carbon (O3/BAC) is being considered as a key component of reverse osmosis-free advanced treatment trains for potable wastewater reuse. Using a laboratory-scale O3/BAC system treating two nitrified wastewater effluents, this study characterized the effect of different ozone dosages (0-1.0 mg O3/mg dissolved organic carbon) and BAC empty bed contact time...

Ozone is a powerful drinking water disinfectant that is effective in treating chlorine resistant organisms, such as Cryptosporidia. For bottled water, ozonation is generally preferred over other available disinfection treatment methods because it does not leave a taste or residual disinfectant, due to ozone’s short lifetime. However, ozonation of drinking water containing bromide can result in ...

Granular activated carbon (GAC) was used to remove bromide (Br⁻) and bromate (BrO(3)(-)) from drinking water in both bench- and pilot-scale experiments. The present study aims to minimize BrO(3)(-) formation and eliminate BrO(3)(-) generated during the ozonation of drinking water, particularly in packaged drinking water. Results show that the Br⁻ and BrO(3)(-) levels in GAC-treated water decrea...

Belousov-Zhabotinsky (BZ) autonomic hydrogel composites contain active nodes of immobilized catalyst (Ru) encased within a nonactive matrix. Designing functional hierarchies of chemical and mechanical communication between these nodes enables applications ranging from encryption, sensors, and mechanochemical actuators to artificial skin. However, robust design rules and verification of computat...

Polarized Raman spectral changes with respect to temperature were investigated for Pr(BrO3)3.9H2O single crystals. FTIR spectra of hydrated and deuterated analogues were also recorded and analysed. Temperature dependent Raman spectral variation have been explained with the help of the thermograms recorded for the crystal. Factor group analysis could propose the appearance of BrO3 ions at sites ...

Trihalomethanes (THMs), a by-product of the chlorination of natural waters containing dissolved organic carbon and bromide, are the focus of considerable public health concern and regulation due to their potential as a carcinogen by ingestion. This paper presents a promising new water treatment process that lowers the concentration of bromide in drinking water and thus, lowers the THM formation...