One of Wastech’s most popular standard products is the CWT-75. The CWT-75 is designed to treat small batches of rinse water – up to 500 gpd - with dissolved heavy metals of various concentrations and complexity. The system features a compact footprint, an ergonomical design with safety in mind, and ease of operation to deliver the same functionality of a large batch system at a ...
The biosorption of Cu(II) and Zn(II) ions from aqueous solution by raw water hyacinth (RWH) and acid treated water hyacinth (TWH) was studied as a function of time, biosorbent dosage and pH. The kinetic results obeyed well the pseudo second–order model. Maximum biosorption capacities for RWH and TWH were measured as 0.49, 6.56 mg/g for Cu(II) and 2.66, 10.71 mg/g for Zn(II), respectively. FT–IR ...
KDF 55 and 85 Provide Non-Chemical Water Treatment Media for Lead Removal and Other Heavy Metal Removal from Water In New Jersey's mercury contaminated groundwater - KDF media have been removing mercury to levels below the MCL since 1992. Redox media, non-chemical water treatment remove up to 98% of water-soluble cations (positively-charged ions) of lead, mercury, copper, nickel, chromium, and ...
Heavy metals are discharged into water from various industries. They can be toxic or carcinogenic in nature and can cause severe problems for humans and aquatic ecosystems. Thus, the removal of heavy metals from wastewater is a serious problem. The adsorption process is widely used for the removal of heavy metals from wastewater because of its low cost, availability and eco-friendly nature. ...
Biosorption is a process of metabolism-independent, passive, physico-chemical binding of metal ions involving non-living biomass, which offers advantages over conventional methods because of cost-effectiveness, especially for dilute metal solutions, and minimal environmental impact. This paper reviews heavy metal biosorption using silvichemical-based biomass materials. It discusses the use of a ...
A heavy metal binding bacterium Pseudomonas putida 5-x was used as biosorbent for heavy metal removal from wastewater. In order to compete with physical adsorbent, the optimisation of the cell preparation technique for further improving its biosorption capacity was conducted. Results showed that the compositions of medium for cell culturing, cell growth age and cell pre-treating technique would ...
As alternative materials for heavy metal removal, this study investigated biosorbents to determine their suitability for permeable reactive barriers. The lead removal efficiencies of brown seaweed (Undaria pinnatifida) and reed (Phragmites australis) were determined under different conditions (batch and column system). The experimental results for these biomaterials fitted the Langmuir isotherm ...
In this study, sorption of lead (II) and chromium (VI) by Ficus religiosa leaves ash (FRLA) was investigated. Batch experiments were performed to study the effects of pH, sorbent dose, temperature and initial metal concentrations. The maximum sorption capacity of lead (II) and chromium (VI) was found to be 68.03 and 38.02 mg g–1, respectively. The optimum pH of 2 and 4 was obtained for chromium ...
Propylthiol-functionalised mesoporous silica SBA-15 prepared by co-condensation has been tested for heavy metal removal. Adsorption from aqueous solution was examined for Cu(II), Pb(II), Cd(II), and Hg(II). Adsorption isotherms were determined at 20°C and Langmuir and Freundlich models were fitted to experimental data. The results from adsorption experiments indicate that mercury is efficiently ...
New nanoporous resin (NPR), based on organic xerogel compounds, was prepared at 150 °C by sol–gel method from pyrogallol and formaldehyde mixtures in water using perchloric acid as catalyst. NPR was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and nitrogen porosimetry. The metal uptake characteristics were explored using ...
This study is focused on isolation of Ni(II), Cu(II) and Cr(VI) resistant bacteria to assess their exopolysaccharide (EPS) production and related bioremoval capacities. Mixed cultures had higher heavy metal removal capacity in media with molasses (MAS) than the control cultures lacking this carbon (AS) containing 50 mg/l of heavy metal. The yields were 32%, 75.7%, and 51.1% in MAS, while the ...
In this study, the removal of Cu(II) from aqueous solutions using living and non–living cultured sludges of different sludge ages was investigated. For non–living sludge, only the metabolism–independent bio–adsorption process occurred and Langmuir model was adequate to describe the adsorption isotherm. When living sludge was used as the adsorbent, a proposed model incorporating the bio–adsorption ...
Crude Diatomites Modified by Microemulsion (DMM) and manganese oxide (MnD) are tested for the removal of chromium (III) in this study. The results indicate that zero point of charge (pHZPC) of DMM is 4.7 and that of MnD is 4.6. Both DMM and MnD show remarkable increase in the sorption capacity of chromium (III) when compared with untreated diatomite, and the removal of chromium (III) by DMM is ...
Release and distribution of heavy metals through industrial wastewaters has adverse affects on the environment via contamination of surface- and ground-water resources. Biosorption of heavy metals from aqueous solutions has been proved to be very promising, offering significant advantages such as low cost, availability, profitability, ease of operation, and high efficiency, especially when ...
Sustainable urban Drainage Systems (SuDS) filter drains are simple, low-cost systems utilized as a first defence to treat road runoff by employing biogeochemical processes to reduce pollutants. However, the mechanisms involved in pollution attenuation are poorly understood. This work aims to develop a better understanding of these mechanisms to facilitate improved SuDS design. Since heavy ...
An adsorbent was prepared by the functionalization of 2-hydroxyacetophenone-3-thiosemicarbazone onto 3-aminopropyl silica by diazotation and characterized by Fourier transmission infra red spectrometry. The functionalized silica was evaluated for removal of lead(II) ions in aqueous solutions. The maximum adsorption capacity 385 μg/g was obtained with an initial concentration of 1,000 μg/L by the ...
Neat cellulose acetate (CA) and CA/polysulfone (PSf) blend ultrafiltration membranes in the presence of polyvinylpyrrolidone as a pore former were prepared via a phase inversion technique. The prepared membranes were characterized by Fourier transform infrared, scanning electron microscopy, mechanical strength, water content, porosity, permeate flux and heavy metals (Pb2+, Cd2+, Zn2+ and ...
LECA zeolite, a novel material containing zeolite crystallised on light expanded clay aggregates (LECA) substrates with the aid of a hydrothermal process, was used in ionic exchange applications. LECA zeolite combines the porosity, low density and good mechanical properties of LECA substrates with the microporosity and ion-exchange properties of zeolites. In the present work, the dynamic ionic ...
The present publication investigates the performance of nanocrystalline Ni (15 wt.%)-doped α-Fe2O3 as an effective nanomaterial for the removal of Cd(II) ions from aqueous solutions. The nanocrystalline Ni-doped α-Fe2O3 powders were prepared by mechanical alloying, and characterized by X-ray diffraction and a vibrating sample magnetometer. Batch-mode experiments were ...