Comparison of Hexavalent Chromium Leaching Levels of Zeoliteand Slag-based Concretes

Abstract In this experiment, the reference concrete samples containing Portland cement as binder and the concrete samples with the addition of ground granulated blast furnace slag (85% and 95%, respectively as replacement of Portland cement) and other samples containing ground zeolite (8% and 13%, respectively as replacement of Portland cement) were analyzed regarding the leachability of chromium. The prepared concrete samples were subjected to long-term leaching test for 300 days in three different leaching agents (distilled water, rainwater and Britton-Robinson buffer). Subsequently, the concentration of hexavalent chromium in the various leachates spectrophotometrically was measured. The leaching parameters as values of the pH and the conductivity were also studied. This experiment clearly shows the need for the regulation and control of the waste addition to the construction materials and the need for long-term study in relation to the leaching of heavy metals into the environment.

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Studies of Predators of the Balsam Woolly Aphid, Adelges piceae (Ratz.) (Homoptera: Adelgidae) VIII. Syrphidae (Diptera),

The Canadian Entomologist ◽

10.4039/ent92801-11 ◽

1960 ◽

Vol 92 (11) ◽

pp. 801-811 ◽

Cited By ~ 3

Author(s):

N. R. Brown ◽

R. C. Clark

Keyword(s):

Life Histories ◽

Population Fluctuations ◽

Term Study ◽

Control Value ◽

Long Term Study ◽

Introduced Predators ◽

Woolly Aphid ◽

Adelges Piceae ◽

And Control

Several species of native syrphids have been found to prey upon the introduced balsam woolly aphid, Adelges piceae (Ratz.), in New Brunswick and three of these, Syrphus torvus O. S., Metasyrphus lapponicus (Zett.), and Neocnemodon coxalis (Curr.), are sometimes very common. As part of a long-term study of the biological control of the balsam woolly aphid by native and introduced predators, the life histories, natural control, population fluctuations and control value of these native syrphids have been investigated.

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Embryo and fetotoxicity of hexavalent chromium: a long-term study

Toxicology Letters ◽

10.1016/s0378-4274(98)00034-4 ◽

1998 ◽

Vol 95 (3) ◽

pp. 165-172 ◽

Cited By ~ 62

Author(s):

Raj Kamal Kanojia ◽

Mohammad Junaid ◽

Ramesh Chandra Murthy

Keyword(s):

Hexavalent Chromium ◽

Term Study ◽

Long Term Study

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Removal of Hexavalent Chromium in Portland Cement Using Ground Granulated Blast-Furnace Slag Powder

Materials ◽

10.3390/ma11010011 ◽

2017 ◽

Vol 11 (1) ◽

pp. 11 ◽

Cited By ~ 7

Author(s):

Sungchul Bae ◽

Fumino Hikaru ◽

Manabu Kanematsu ◽

Chiaki Yoshizawa ◽

Takafumi Noguchi ◽

...

Keyword(s):

Blast Furnace ◽

Portland Cement ◽

Hexavalent Chromium ◽

Blast Furnace Slag ◽

Slag Powder ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

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Mechanisms Accompanying Chromium Release from Concrete

Materials ◽

10.3390/ma13081891 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1891 ◽

Cited By ~ 1

Author(s):

Anna Król

Keyword(s):

Portland Cement ◽

Building Materials ◽

Portland Cement Concrete ◽

Chromium Release ◽

Granulated Blast Furnace Slag ◽

Diffusion Controlled ◽

Tank Test ◽

Mineral Additives ◽

Furnace Slag

The use of mineral additives from the power and metallurgy industries in the production of building materials still raises questions about the ecological safety of such materials. These questions are particularly associated with the release of heavy metals. The article presents research related to the leaching of chromium from concretes made of Portland cement CEM I and slag cement CEM III/B (containing 75% of granulated blast furnace slag). Concrete was evaluated for leaching mechanisms that may appear during tank test over the long term (64 days). It has been presented that the dominating process associated with the leaching of chromium from both types of concrete is surface wash-off. Between the 9th and 64th day of the test, leaching of Portland cement concrete can be diffusion controlled. It has been proven that the participation of slag in the composition of concrete does not affect the level of leaching of chromium into the environment from concrete.

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