Residual Total Organic Carbon Research Articles

Oxidative degradation of dyes and surfactant in the Fenton and photo‐Fenton treatment of dyehouse effluents

The oxidative degradation of two dyes and a nonionic surfactant by iron(II) sulphate and hydrogen peroxide (Fenton's reagent) was studied, in the presence of UV irradiation (photo‐Fenton process). The degradation kinetics were followed by measuring the residual total organic carbon (TOC) value as a function of time at different initial TOC concentrations and temperatures. The curves interpolating the kinetic data show that the residual TOC values attained a stable level after a given treatment time; a similar trend was observed in the treatment of some dyehouse effluent samples. Moreover, by fitting experimental data, a first‐order equation was obtained that can explain the kinetic model proposed.

Fundamental Study on the Production of Ultrapure Water. VI

This paper describes the removal of leachables by adsorption from typical strong base anion exchange resins (SBAER, one porous and one gel type, OH form). The absorbents used for this purpose were strong acid cation exchange resins (SACER, H form) paired to each SBAER and synthetic spherical carbonaceous absorbents.The leachables were obtained by soaking SBAERs in purified water of less than 100 μgC/L of total organic carbon (TOC) at elevated temperature (60°C). The leachables contained components with molecular weights (MW as a polystyrenesulfonate) of 1, 600 (hidden by MW 2, 200 peak), 2, 200, 4, 000 and 5, 900 as determined by gel filtration chromatography. Some components were shown to be present in the low MW leachables by reverse phase chromatography, though they did not include trimethylamine and methyl alcohol. A maximum 96. 80 % of TOC in the leachables was removed from SBAERs with SACERs. The MW 4, 000 component, trimethylamine, and low MW leachables except for a non-ionic hydrophilic component of MW less than 186 were removed almost completely by SACERs. The carbonaceous adsorbent having strongly hydrophobic surface adsorbed well the residual leachable component which could not be removed by SACERs. Residual TOC removal with the absorbent was about 65 %.

Treatment of Tar Sand Wastewaters with Activated Carbon, Ozone and Reverse Osmosis

Tar sand deposits offer long-term potential for satisfying future energy needs. Two large field-scale extraction experiments near Vernal, Utah, employed either a sequenced reverse-forward combustion technique (TS-2C) or a steam flooding procedure (TS-1 S) to recover in-place bitumen. This report documents the evaluation of activated carbon, ozone and reverse osmosis in treating the two types of tar sand wastewaters. Substrates included untreated and pretreated (filtration, foam fractionation, chemical treatment with ferric chloride) TS-1S and TS-2C wastewaters. Activated carbon, at a dose of 1,000 mg/L, reduced the Total Organic Carbon (TOC) of TS-1 S wastewater after treatment by 350 mg/L of ferric chloride to 2.3 mg/L TOC, a reduction of 91.6%. At the same adsorbent dos, activated carbon reduced the TOC in TS-2C wastewater from 678 mg/L to 546 mg/L. A study of the six commercially available adsorbents yielded little difference in adsorption capability for either wastewater. Ozonation of TS-lS wastewater after pretreatment by either foam fractionation or chemical treatment with ferric chloride then activated carbon yielded residual TOC levels of less than 1.2 mg/L. Reverse osmosis (RO) studies included investigation of four membrane types (cellulose acetate, poly-ether amide, poly-ether urea and a noncellulosic on a poly-sulfone base), three applied pressure levels (250, 400 and 550 psig) and two solution pH levels (5.5 and 7.8) with 5.0 µ (micron) filtered TS-2C wastewater as the substrate. A two-stage RO process achieved maximum organic and inorganic rejections of 98% and 97%, respectively.