0000000000535616
AUTHOR
S. Tahiri
showing 10 related works from this author
Separation of motor oils, oily wastes and hydrocarbons from contaminated water by sorption on chrome shavings
2007
In this paper, the ability of chrome shavings to remove motor oils, oily wastes and hydrocarbons from water has been studied. To determine amount of hydrocarbons sorbed on tanned wastes, a FT-NIR methodology was used and a multivariate calibration based on partial least squares (PLS) was employed for data treatment. The light density, porous tanned waste granules float on the surface of water and remove hydrocarbons and oil films. Wastes fibers from tannery industry have high sorption capacity. These tanned solid wastes are capable of absorbing many times their weight in oil or hydrocarbons (6.5-7.6g of oil and 6.3g of hydrocarbons per gram of chrome shavings). The removal efficiency of the…
Determination of total phenolic compounds in compost by infrared spectroscopy
2016
Abstract Middle and near infrared (MIR and NIR) were applied to determine the total phenolic compounds (TPC) content in compost samples based on models built by using partial least squares (PLS) regression. The multiplicative scatter correction, standard normal variate and first derivative were employed as spectra pretreatment, and the number of latent variable were optimized by leave-one-out cross-validation. The performance of PLS-ATR-MIR and PLS-DR-NIR models was evaluated according to root mean square error of cross validation and prediction (RMSECV and RMSEP), the coefficient of determination for prediction ( R pred 2 ) and residual predictive deviation (RPD) being obtained for this la…
Immobilization of vegetable tannins on tannery chrome shavings and their use for the removal of hexavalent chromium from contaminated water
2011
Abstract Chestnut (C) and mimosa (M) tannins immobilized on chrome shavings (CS) as an adsorbent have been proposed to be an efficient and economical alternative in hexavalent chromium removal from aqueous solutions. The adsorption of hexavalent chromium onto chrome shavings-tannin (CS-T) adsorbents was performed using batch equilibrium technique at 25 ± 2 °C. The effect of pH is highly important especially in the case of high concentrations of hexavalent chromium. The maximum chromium uptake was obtained at pH 4. Two hours of contact time are enough to reach equilibrium. Sorption of chromium on CS-T was found to follow a pseudo-second order kinetic model (with correlation coefficients grea…
Preliminary Results on the Use of Leather Chrome Shavings for Air Passive Sampling
2012
A new passive sampler based on low-density polyethylene (LDPE) layflat tube filled with chrome shavings from tannery waste residues was evaluated to determine volatile organic compounds (VOCs) in indoor and outdoor areas. VOCs were directly determined by head space-gas chromatography-mass spectrometry (HS-GC-MS) without any pretreatment of the sampler and avoiding the use of solvents. Limit of detection values ranging from 20 to 75 ng sampler−1and good repeatability values were obtained for VOCs under study with relative standard deviation values from 2.8 to 9.6% except for carbon disulfide for which it was 22.5%. The effect of the amount of chrome shavings per sampler was studied and resul…
Kinetic, isotherm and thermodynamic studies of the adsorption of methylene blue dye onto agro-based cellulosic materials
2015
AbstractThe purpose of this work is to establish the optimal experimental conditions for the removal of methylene blue (MB-as model basic dye) from aqueous solution by adsorption onto four agro-based materials, namely, cedar sawdust, pine sawdust, wheat straw, and Provence cane Arundo donax. Results show that an increase in acidity or ionic strength of the medium has generally a negative effect on the discoloration yield. From the data of pH effect, there is no need to change the initial pH of the MB solution to be treated. Equilibrium was reached after 20−30 min of agitation when cedar sawdust, pine sawdust, and Provence cane are used as adsorbents. However, in the case of wheat straw, an …
Management of tannery wastewaters: treatment of spent chrome tanning bath and vegetable tanning effluents
2013
Abstract In this work, a chain of treatment processes was proposed and described in order to reach better management of mineral and vegetable tannery wastewaters. First, chromium was precipitated from the spent chrome tanning bath by sodium hydroxide (NaOH) and then reformulated to form a complex of basic chromium sulfate which was tested successfully in mineral tanning process. On the other hand, the supernatant recovered after precipitation of chromium with NaOH was used to dilute vegetable tanning wastewaters characterized by a high concentration of polyphenols (about 2,574 mg/L). Diluted effluent was then treated by liming and tangential microfiltration using a ceramic membrane based on…
Research on Spectroscopy in Morocco from 1984 to 2006
2007
Abstract The evolution of spectroscopy‐based research activity in Morocco was evaluated on the basis of publications that have appeared in the Science Citation Index, Expanded (SCI), during the cumulative period 1984–2006 (September). The most active research groups, and their universities or centers, were identified in this subject from their scientific production in the first years of this century. The preference to publish in specific journals, the main areas of interest to Moroccan authors, and the spectroscopy techniques most commonly employed for their studies were also appraised. This scientometric study was undertaken to introduce a group of papers in a special issue of Spectroscopy…
Utilisation de dérayures de cuir tanné au chrome pour la décontamination des eaux polluées par les colorants et les huiles
2007
Abstract Les dérayures du cuir ont montré une grande capacité d'adsorption des colorants organiques directs. La capacité maximale de rétention est de 333,3 mg/g et de 312,5 mg/g respectivement pour les colorants DR75 et DR80. Un pH acide et une température de l'ordre de 50°C sont favorables à la décoloration. Les essais ont révélé la faisabilité de la décontamination d'un rejet de textile par les dérayures. Le taux d'épuration peut dépasser 90 p.100 dans des conditions précises de pH et de température. Les dérayures brutes et saturées par le colorant DR80 ont montré également une grande capacité d'absorption des huiles (5 à 6,5 g/g). En milieu aqueux, ces déchets fibreux réagissent fortemen…
Removal of Hexavalent Chromium from Aqueous Solutions Using Biopolymers
2018
AbstractTwo biopolymers were prepared by reaction of chestnut and quebracho tannins with gelatin extracted from untanned hide wastes. Obtained biopolymers were evaluated as adsorbents for removing ...
Prediction of organic carbon and total nitrogen contents in organic wastes and their composts by Infrared spectroscopy and partial least square regre…
2017
Middle and near infrared (MIR and NIR) were employed to determine organic carbon (OC) and total nitrogen (TN) in different soil organic amendments including wastes, composts and mixtures of composts and organic wastes. Prediction models based on partial least squares (PLS) regression from the spectra of untreated samples were built. Different spectra preprocessing strategies were adopted and the best number of latent variable was evaluated using leave-one-out cross-validation. Attenuated total reflectance (PLS-ATR-MIR) and diffuse reflectance (PLS-DR-NIR) models were built and evaluated from root mean square error of cross validation and prediction (RMSECV and RMSEP), coefficients of determ…