The development of slow-release chemical oxidants for sub-surface remediation is a relatively new technology. Our objective was to develop slow-release persulfate-paraffin candles to treat BTEX-contaminated groundwater. Laboratory-scale candles were prepared by heating and mixing Na(2)S(2)O(8) with paraffin in a 2.25 to 1 ratio (w/w), and then pouring the heated mixture into circular molds that...

Remediation of hydrocarbon contaminated soils can be performed both in situ and ex situ using chemical oxidants such as sodium persulfate. Standard methods for quantifying persulfate require either centrifugation or prolonged settling times. An optimized soil extraction procedure was developed for persulfate involving simple water extraction using a modified disposable syringe. This allows cons...

The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB) in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1) was used at a given mass ratio of solution to soil (20:1) to extract NB contaminated soil (47.3 mg kg-1), resulting in NB desorption removal efficient of 7...

OBJECTIVE Hairdressers have an increased risk for airway symptoms especially when using hair-bleaching powder containing persulfate. To minimize exposure, dust-free bleaching powder (DFP) has been made available. We studied the effects of regular powder (RP) or DFP on the airway symptoms of hairdressers with hair-bleaching associated rhinitis. METHODS Twelve hairdressers each performed three ...

A dendrimer amphiphilic polymer (A-D-HPAM) was synthesized by aqueous solution polymerization of acrylic acid (AA), acrylamide (AM), 2-acrylamido-2-methyl-1-propane sulfonic (AMPS), hydrophobic monomer cetyl dimethyl allyl ammonium chloride (DMCAAC-16), and skeleton GA1.0, using persulfate sodium bisulfite as initiators. The chemical structure A-D-HPAM was, respectively, analyzed Fourier transf...

In this paper, the fabrication of ZnO tetrapod was investigated. It synthesized by thermal oxidation technique using metal zinc powder mixed with oxidizing agents such as hydrogen peroxide (H2O2) and ammonium persulfate ((NH4)2S2O8). The furnace heating temperature reached at 1000 °C in air. average diameter length a leg for mixture H2O2 from SEM were 45.3 nm 1.57 μm, respectively. oxygen vacan...

In this work, polymerizations of styrene (St) in the presence divinylbenzene (DVB) as a crosslinking agent and sodium 4-vinylbenzenesulfonate (VBS) have been performed Pickering emulsions, using silica nanoparticles (SNps) stabilizing agents ammonium persulfate hydrophilic initiator. oil-in-water emulsions with alkaline continuous phase (pH = 9) at 1, 2, 3 wt% DVB (relative to St), polydisperse...