Compositions and methods for removing arsenic in water

A technology for pollutants and aqueous solutions, which can be used in chemical instruments and methods, separation methods, solid adsorbent liquid separation, etc., and can solve problems such as expensive

Inactive Publication Date: 2008-04-16
RGT UNIV OF CALIFORNIA
View PDF2 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But this method is still relatively expensive and requires a complex set of operations in a reactor that requires pressure drop and many technical management and monitoring

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Compositions and methods for removing arsenic in water
  • Compositions and methods for removing arsenic in water
  • Compositions and methods for removing arsenic in water

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0067] Example 1 Using Bottom Ash as a Representative Substrate

[0068] In one embodiment, bottom ash from a power plant in an area with water to be treated may be used. Coal-fired thermal power plants in South Asia, for example, produce large quantities of bottom ash suitable for use in the present invention. This bottom ash is a fine powder material of spherical particles without minerals, mainly containing silicates of iron, magnesium and aluminum. The particle size is generally 1-10 microns, providing a surface area to volume ratio of approximately 0.5m 2 / cm 3 . Disposal of bottom ash material from such thermal power plants cost US$ 5 per ton in 2005. The present invention can use a simple chemical method to coat the bottom ash with iron hydroxide and / or iron oxyhydroxide at room temperature, without using expensive raw materials and high energy consumption.

[0069] 1 kg of this medium can remove 0.7 g of elemental arsenic from drinking water, which is equivalent t...

Embodiment 2

[0079] The preparation of embodiment 2 5 grams of pretreatment bottom ash

[0080] First place 5 g of dry bottom ash in a collection container.

[0081]30ml of 0.6M FeSO 4 Mix with the bottom ash and continue stirring for 1 hour at a temperature close to room temperature, eg 10-40°C. Although this is FeSO 4 A saturated solution at room temperature, but lower concentrations may be used for lower surface coverage of the bottom ash or for smaller quantities of bottom ash. Available FeSO 4 The concentration is from 0.1M or greater.

[0082] After stirring, solid bottom ash particles are allowed to settle to the bottom of the collection container within about 5 minutes. At this point the superficial liquid was removed, this liquid was filtered, and the residue on the filter paper was added to the dense solid at the bottom of the collection vessel.

[0083] Then add 5ml of 0.5N aqueous NaOH to the collection vessel and stir to mix for 5 minutes. It can be considered that the ...

Embodiment 3

[0089] Example 3 Removal of Arsenic Using Pretreated Bottom Ash

[0090] In practice, combining arsenic-containing water sources with Fe(OH) 3 The applied render is thoroughly mixed to reduce the arsenic content to acceptable levels. Currently, the acceptable level stipulated by the US Environmental Protection Agency (USEPA) is 50ppb, but since January 2006, the acceptable value has been reduced to 10ppb. The World Health Organization (WHO) has announced that the lower limit of the interim value for the recommended acceptable arsenic concentration in drinking water is changed to below 10 ppb.

[0091] The arsenic-containing water is pretreated with ultraviolet light, so that the state of arsenic in the water changes from As 3+ to As 5+ , can improve the adsorption performance. Normally, clear water lets UV light through without absorbing it. But after adding coloring agent or color core source, ultraviolet light will be absorbed, provide energy for ions, and change the va...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

Compositions and methods and for contaminants from water are provided. The compositions comprise ferric hydroxide and ferric oxyhydride coated substrates for use in removing the contaminant from the water. Contacting water bearing the contaminant with the substrates can substantially reduce contaminant levels therein. Methods of oxidizing the contaminants in water to facilitate their removal by the ferric hydroxide and ferric oxyhydride coated substrates are also provided. The contaminants include, but are not limited to, arsenic, selenium, uranium, lead, cadmium, nickel, copper, zinc, chromium and vanadium, their oxides and soluble salts therof.

Description

[0001] related application [0002] This application claims priority to the following US provisional patent applications: 60 / 674,835, filed April 25, 2005, and 60 / 679,393, filed May 9, 2005, the entire contents of which are incorporated herein by reference. This application is related in subject matter to the following U.S. patent applications: 11 / 065,867 filed February 24, 2005, 60 / 653,073 filed February 14, 2005, and 60 / 550,688 filed March 4, 2004, all of which The contents are incorporated herein by reference. [0003] Statement Regarding Invention Rights Under Federally Funded Research and Development [0004] This invention was made pursuant to Basic Contract No. DE-AC03-76SF00098 between the U.S. Department of Energy and the Regents of the University of California for the management and operation of Lawrence Berkley National Laboratory. The US Government has certain rights in this invention. [0005] References to Sequential Catalogs, Tables, or Computer Program Catalog...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B01D15/00
Inventor A·J·加吉尔
Owner RGT UNIV OF CALIFORNIA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap