Use of low-cost biological wastes and vermiculite for removal of chromium from tannery effluent.
Biological wastes (sawdust, rice husk, coirpith and charcoal) and a naturally occurring mineral (vermiculite) have been tested for their effectiveness in removing Cr from tannery effluent through batch and column experiments. The adsorption capacities of the substrates were also evaluated using isotherm tests and computing distribution co-efficient. The sawdust exhibited a higher adsorption capacity (k = 1482 mgkg(-1)), followed by coirpith (k = 159 mgkg(-1)). The biosorbent and mineral vermiculite in columns were found very effective in removing Cr from tannery effluent. About 94% removal of Cr was achieved by a column of coirpith, and equally (93%) by a column containing a mixture of coirpith and vermiculite. This study showed that biological wastes are potential adsorbents of Cr, which could be successfully used to reduce the Cr concentrations in tannery effluent.
Sumathi
K M S
KM
Department of Environmental Sciences, Tamil Nadu Agricultural University, Coimbatore 641 003, India.
Mahimairaja
S
S
Naidu
R
R
D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry*; D002606:Charcoal; D002857:Chromium / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013633:Tanning; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D014866:Waste Products; D014934:Wood
D000538:Aluminum Silicates; D014866:Waste Products; D002857:Chromium; C003760:vermiculite; D002606:Charcoal