Biomorphic nano-hydroxyapatite (HAP) was fabricated by a co-precipitation method using cotton as bio-templates and employed in adsorptive removal of ofloxacin (OFL) and triclosan (TCS) that are two representative pharmaceuticals and personal care products (PPCPs). The surface area and porosity, crystal phase, functional group, morphology and micro-structure of the synthesized HAP were characterized by Brunauer–Emmett–Teller isotherm, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron macroscopic and transmission electron microscopy. The effects of initial pH, ionic strength, initial concentration, contact time and temperature on the removal of PPCPs were studied in a batch experiment. The adsorption of OFL and TCS was rapid and almost accomplished within 50 min. Kinetic studies indicated that the adsorption process of OFL and TCS followed the pseudo-first-order and pseudo-second-order models, respectively. The Freundlich isotherm described the OFL adsorption process well but the adsorption of TCS fitted the Langmuir isotherm better. Thermodynamics and isotherm parameters suggested that both OFL and TCS adsorption were feasible and spontaneous. Hydrogen bond and Lewis acid–base reaction may be the dominating adsorption mechanism of OFL and TCS, respectively. Compared to other adsorbents, biomorphic HAP is environmentally friendly and has the advantages of high adsorption capacity, exhibiting potential application for PPCPs removal.
Horizon and water treatment
Horizon is an environment company focused on water treatment.In the latest years,with the improvement of industrial economy,water quality is becoming worse and worse.To prevent the pollution trend,our government has raised the standard of sewage discharge several times,so traditional process and technology of water treatment can’t apply for the environmental requirements and technology revolution and innovation are necessary.In the recent years,many company and community have improved products to meet...
Santa Cruz Meets THM/DBP Challenge with Unique Air Stripping Process - Case Study
SummarySanta Cruz has successfully demonstrated an innovative way for the City to meet its water quality goals while using process recycled water as part of its supply source. Using the recycled water had caused concern about reliably meeting the U.S. EPA THM/DBP potable water quality standards in its finished water. The City evaluated various aeration treatment processes and chose an E-Z Tray® Air Stripper from QED as the best fit for meeting their water quality and O&M goals. The EZ Tray air stripper...
Numerical routing of tracer concentrations in rivers with stagnant zones
Modeling pollution transmission in rivers is an important subject in environmental engineering studies. Numerical approaches to modeling pollution transmission in rivers are useful tools for managing the water quality. The advection-dispersion equation is the governing equation in the transport of pollution in rivers. Recently, due to advances in fractional calculus in engineering modeling, the simulation of pollution transmission in rivers has been improved using the fractional derivative approach. In this...
Modeling Tip: Importing & Exporting Traffic Data in CALRoads View
The CALINE series of models was developed to estimate pollutant concentrations from motor vehicles at roadway intersections. It includes three primary models: CALINE, CAL3QHC, and CAL3QHCR. The latter allows processing of real meteorological data (up to one year) and input of vehicular emissions, traffic volume, and signalization (ETS) data. Data reflecting traffic conditions for individual hours of a week can be input into CAL3QHCR. Lakes Environmental recently released CALRoads View Version 6.5 which includes...
Study shows online consumers want environmentally friendly options
Reducing the carbon footprint of what we buy isn’t easy, but the opportunity for impact is substantial: In the United States, producing and delivering consumer purchases releases twice as much carbon into the atmosphere as home energy use and personal travel. By gathering and sharing information on carbon emissions associated with their products, companies can make environmentally friendly choices easier for consumers and boost their own reputations as planet-friendly businesses. Advances in online technolog...