Seiki Tanada

In vitro adsorption removal of paraquat by activated carbon and cation exchange Resin

With the modernization of agriculture, environmental pollution and accidental poisoning by agricultural chemicals have become a great social problem. With the remarkable increase in the amount of paraquat used, the number of deaths by swallowing of paraquat has also increased in recent years. Presently, an effective antidote and treatment for paraquat poisoning is not available. For primary treatment, administration of an adsorbent is done at the same time as gastrointestinal lavage. As an adsorbent for paraquat poisoning, the efficacy of activated carbon, Fullers Earth, bentonite, and a cation exchange resin have been reported. In this work, the authors discuss the adsorption characteristics of paraquat in artificial gastric juice and normal saline solution.

Increase in micropore volume of N-containing activated carbon treated with methylol melamine urea solution

The micropore volume of N-containing activated carbon was increased and the average radius of supermicropore was extended by treatment with methylol melamine urea solution.

Adsorption Removal of Benzalkonium Chloride by Granular Activated Carbon for Medical Waste Water Treatment

The adsorption removal of benzalkonium chloride disinfectant by granular activated carbon is discussed. The adsorption isotherm of benzalkonium chloride was expressed by the Freundlich equation. A significant correlation was found between the amount of benzalkonium chloride adsorbed in less than 1000 ppm of equilibrium concentration and the micropore volume of activated carbon. As for the adsorption rate, a change in intraparticle diffusiveness was found with increasing adsorption ratio. No significant correlation between the values of intraparticle diffusiveness and the properties of activated carbon was found. It was concluded that the micropore volume of activated carbon was the dominant factor in the adsorption removal of benzalkonium chloride by granular activated carbon.

Adsorption of indigo carmine by activated carbon

Abstract Adsorption of indigo carmine as an acid dye onto activated carbon was studied in order to elucidate its adsorption behavior on the basis of amount adsorbed, pore size distribution, pH and basicity of activated carbon, and pH of filtrate. Activated carbon No.1 and No.4 were the preferable adsorbents for removing indigo carmine in the range of higher and lower equilibrium concentration, respectively. An approximately linear relationship existed between the pore volume with radius of less than 200 A and the amount adsorbed.

Intraparticle diffusivity of methylene blue into pores of pyrolysis ashes derived from sewage sludge

Abstract The adsorption properties of pyrolysis ash derived from sewage sludge were investigated. The differences of pyrolysis ash sampled in April and October were examined on the basis of the results of analytical value, amount of methylene blue adsorbed, intraparticle diffusivity, and pore size distribution. The carbon content of pyrolysis ash sampled in April was 4 times as large as that sampled in October. The amount adsorbed and intraparticle diffusivity of methylene blue onto pyrolysis ash sampled in April were 1.5 times and 1.3 times, respectively, as large as those onto pyrolysis ash sampled in October.

Thermodynamics of adsorption and desorption of hydrogen sulfide in micropores of activated carbon

Thermodynamics of adsorption and desorption of hydrogen sulfide in micropores of activated carbon have been studied on the basis of q and ΔS. The values of q and ΔS of adsorption were larger than those of desorption.

Adsorption of styrene monomer on activated carbon.

A study of adsorption isotherms of styrene on activated carbon at 30C by a gravimetric method showed that activated carbon with a 0.2665 ml/g micropore volume at pH 6.3 gave optimal styrene removal at equilibrium concentrations of less than or equal to 1000 ppM, and that micropore volumes of 0.6216 ml/g at pH 6.7 gave optimal removal at > 2000 ppM. The mechanism of adsorption was studied by determining the relationship between the amount adsorbed at 4000 ppM at equilibrium and the pH, pore volume, and pore size distribution.