Waste Minimization In Semiconductor Processing

1994 ◽  
Vol 344 ◽  
Author(s):  
Steven J. Hardwick ◽  
Joanne C. Mailloux

AbstractThe US semiconductor industry uses 5–7 thousand pounds of arsine annually. Fifty to eighty percent of the arsine used becomes a waste product, which requires abatement. Traditional methods of abatement are reviewed with an emphasis on dry chemical scrubbing. A variety of dry chemical scrubbing materials were evaluated for arsine capacity, using activated carbon as the baseline for comparison. A proprietary mixed oxide composition, employing copper oxide as the active ingredient was identified as having high capacity and efficiency. Disposal and possible reclamation options are discussed.

2019 ◽  
Author(s):  
Luke Skala ◽  
Anna Yang ◽  
Max Justin Klemes ◽  
Leilei Xiao ◽  
William Dichtel

<p>Executive summary: Porous resorcinarene-containing polymers are used to remove halomethane disinfection byproducts and 1,4-dioxane from water.<br></p><p><br></p><p>Disinfection byproducts such as trihalomethanes are some of the most common micropollutants found in drinking water. Trihalomethanes are formed upon chlorination of natural organic matter (NOM) found in many drinking water sources. Municipalities that produce drinking water from surface water sources struggle to remain below regulatory limits for CHCl<sub>3</sub> and other trihalomethanes (80 mg L<sup>–1</sup> in the United States). Inspired by molecular CHCl<sub>3</sub>⊂cavitand host-guest complexes, we designed a porous polymer comprised of resorcinarene receptors. These materials show higher affinity for halomethanes than a specialty activated carbon used for trihalomethane removal. The cavitand polymers show similar removal kinetics as activated carbon and have high capacity (49 mg g<sup>–1</sup> of CHCl<sub>3</sub>). Furthermore, these materials maintain their performance in real drinking water and can be thermally regenerated under mild conditions. Cavitand polymers also outperform activated carbon in their adsorption of 1,4-dioxane, which is difficult to remove and contaminates many public water sources. These materials show promise for removing toxic organic micropollutants and further demonstrate the value of using supramolecular chemistry to design novel absorbents for water purification.<br></p>


2011 ◽  
Vol 366 ◽  
pp. 412-415
Author(s):  
Yu De Liu ◽  
Bo Quan Jiang ◽  
Zheng Qiang Xiao

The activated carbon loaded copper oxide catalyst was prepared from Hainan abandoned coconut shells using chemical activation method and applied in treatment of acid bright red GR simulation dyeing wastewater. The effects of phosphoric acid concentration, ratio of liquid to solid, activation time and activation temperature on the COD and color removal rates were investigated by orthogonal experiment. The results showed that the optimal values of the parameters above were 65% (in mass), 3:1, 2.5h and 500°C under the designed copper oxide loading conditions of calcining temperature 300°C,calcining time 3.0 h and use level of copper nitrate 15 mL. Using the prepared sample for the treatment of the wastewater, the COD and color removal rates reached 94.384% and 99.840%, respectively.


2013 ◽  
Vol 68 (6) ◽  
pp. 1370-1376 ◽  
Author(s):  
M. Grivé ◽  
D. García ◽  
C. Domènech ◽  
L. Richard ◽  
I. Rojo ◽  
...  

Granular activated carbon (GAC) is commonly used as adsorbent in water treatment plants given its high capacity for retaining organic pollutants in aqueous phase. The current knowledge on GAC behaviour is essentially empirical, and no quantitative description of the chemical relationships between GAC surface groups and pollutants has been proposed. In this paper, we describe a quantitative model for the adsorption of atrazine onto GAC surface. The model is based on results of potentiometric titrations and three types of adsorption experiments which have been carried out in order to determine the nature and distribution of the functional groups on the GAC surface, and evaluate the adsorption characteristics of GAC towards atrazine. Potentiometric titrations have indicated the existence of at least two different families of chemical groups on the GAC surface, including phenolic- and benzoic-type surface groups. Adsorption experiments with atrazine have been satisfactorily modelled with the geochemical code PhreeqC, assuming that atrazine is sorbed onto the GAC surface in equilibrium (log Ks = 5.1 ± 0.5). Independent thermodynamic calculations suggest a possible adsorption of atrazine on a benzoic derivative. The present work opens a new approach for improving the adsorption capabilities of GAC towards organic pollutants by modifying its chemical properties.


2014 ◽  
Vol 23 (5) ◽  
pp. 662-668 ◽  
Author(s):  
Bingsi Liu ◽  
Wenshuo Wang ◽  
Na Wang ◽  
(Peter) Chak Tong Au

1984 ◽  
Vol 38 ◽  
Author(s):  
Joda C. Wormhoudt ◽  
Alan C. Stanton ◽  
Joel A. Silver

AbstractTwo processes of great importance in the semiconductor industry are vapor deposition and plasma etching. This paper presents a review of laser techniques for spectroscopic characterization of the gas phase species involved in these processes. Band strength and other spectroscopic data for selected molecules are used to give estimates of the detection sensitivity in vibrational and electronic bands. Preliminary results are given from work presently in progress in our laboratory on the detection of such species. The discussion includes examples of the application of these techniques to a number of laboratory deposition and etching devices.


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