Simulated Industrial Effluent Research Articles

Al nanoparticles coated with polyaniline and functionalized modified multi-walled carbon nanotubes (MWCNT) for removal of Ni2+ and Zn2+ from a simulated industrial effluent

Al nanoparticles coated with polyaniline and functionalized modified multi-walled carbon nanotubes (MWCNT) for removal of Ni2+ and Zn2+ from a simulated industrial effluent

Remarkable dye adsorption capabilities in CaO-Doped-Zirconia systems

The realm of dye adsorption involving zirconia systems remains an untapped frontier, awaiting the unveiling of its complete prowess. The present work investigates the adsorption potentials of CaO-doped ZrO2 nanoparticles with varying doping of CaO (0, 7, 10, and 16 mol.%). With the highest adsorption capacity (of 760 mg/g) reported ever for any zirconia system, the 16 mol.% CaO-doped ZrO2 (16CaSZ) ultrafine nanoparticles portrayed fastest kinetics of dye (Congo red) removal. Along with effect of different pHs (in the presence of different anions such as Cl-, NO3–, SO42- and the mixture of them), a simulated wastewater (comprising urea, different salts, dye, sand, grass, engine oil etc.) was made to examine the efficacy of our nano-adsorbent. The 16CaSZ nanoparticles depicted excellent adsorption (∼99 %) in simulated industrial effluent and duplicated the same performance for pHs ranging from 2 to 10. Multitude of factors (e.g., phase-pure cubicity, highest oxygen vacancy content, pronounced surface area etc.) were credited for this chemisorption-based (R-SO3- interactions, as revealed by the structural and spectroscopic investigations on the post-adsorption products) remarkable adsorption process.

Highly effective removal of multi-heavy metals from simulated industrial effluent through an adsorption process employing carboxymethyl-chitosan composites

Monochloroacetic acid precursor-based carboxymethyl chitosan resins were prepared using the chitosan with variant molecular weight. The carboxymethylation assured enhanced active sites on the resin surface, acidic media stability, and henceforth its appropriate constitution to facilitate enhanced multi-heavy metal adsorption-desorption and subsequent regeneration potential. Zn, Pb, and Fe multimetal adsorption properties were investigated. Thereby, kinetic and equilibrium models were sought for their fitness to represent heavy metal sorption data with the preferred complex adsorbate system. The adsorbate system complexity and its constituent co-existing cations significantly influence the sorption characteristics of the mentioned multi-heavy metal ions. The optimal adsorption capabilities for Zn, Pb, and Fe were 238.10 mg g−1, 4.78 mg g−1, and 147.06 mg g−1, respectively. Low-cost acid-base solutions were also considered for the effective regeneration of the resin even after three adsorption-desorption cycles. Prominent findings of the work assured excellent functionality of the carboxymethyl-chitosan resin for the simultaneous lead, iron, and zinc ion elimination from mimicking real-world effluent systems.

KOH activated carbons from Brazil nut shell: Preparation, characterization, and their application in phenol adsorption

Activated carbons named AC105 and AC11 were prepared from Brazil nut shells using the weight ratios of Brazil nut shells: KOH of 1:0.5 and 1:1, respectively. The prepared materials were characterized using different techniques and applied to remove phenol from the aqueous solution through adsorption. The characterization data showed that both materials presented similar properties, with AC11 exhibiting a slightly higher specific surface area (332.2 m2 g–1) than AC105 (314.3 m2 g–1). The kinetic study showed that AC11 reached the process equilibrium faster than AC105, and the Elovich model was best suited to the kinetic data for both adsorbents. The equilibrium data followed the Sips model; the maximum adsorption capacities were 55.16 and 68.52 mg g–1 for AC105 and AC11, respectively. The application of the materials in the treatment of a simulated industrial effluent showed removal efficiencies of 28.05% and 48.20% for AC105 and AC11, respectively. Therefore, through the adsorption results, AC11 proved to be more efficient towards phenol removal and is a promising alternative for treating wastewater containing this contaminant.

Simultaneous removal of cationic and anionic dyes from simulated industrial effluents using a nature-inspired adsorbent

Alginate-grafted polyaniline (Alg-g-PANI) microparticles were synthesized through the grafting of aniline onto functionalized Alg followed by double crosslinking by glutaraldehyde and calcium chloride. The performance of the developed microparticles as adsorbent in simultaneous removal of malachite green (MG) and congo red (CR) dyes were examined by the batch method. Experimental parameters, including adsorbent amount, pH, initial dyes concentrations, and contact time were optimized. Langmuir and Freundlich adsorption models were employed to explore the equilibrium isotherm. As the Langmuir model results, the maximum adsorption capacities (Qm) of microparticles for the MG and CR dyes were obtained as 578.3 and 409.6 mgg−1, respectively. Adsorption kinetics for both dyes were well-fitted with the pseudo-second-order model that confirm the rate-limiting step might be the chemical adsorption. The adsorbent was regenerated via desorption process and was reusable five times without a substantial decrease in its adsorption efficacy in first three cycles. Adsorbent-dyes interactions were computationally evaluated using Gromacs package, and it was found that both MG and CR are able to interact strongly with the adsorbent. In accordance with experimental results, simulation data revealed that MG can be removed more efficiently than those of the CR. As the experimental results, we could conclude that the synthesized Alg-g-PANI microparticles can be used as a nature-inspired adsorbent for simultaneous removals of CR and MG dyes.

Aqueous Adsorptive Removal of Bisphenol A Using Tripartite Magnetic Montmorillonite Composites

The adsorption of bisphenol A into untreated montmorillonite clay, doped titanium composite and cationic polymer modified tripartite magnetic montmorillonite composite was investigated under different conditions. The magnetic property of the modified adsorbent was ascertained by action of external magnetic field on the materials when dispersed in aqueous media. The XRD results for the unmodified and modified adsorbents showed that interlayer spacing of the clay material increases due to intercalation of the precursor molecules. The textural properties of the adsorbents from BET analysis showed that pore size and specific surface area of the tripartite magnetic composite was calculated to be 288.08 m2/g while that of the unmodified clay was 90.39 m2/g. The TGA results showed the tripartite magnetic composite was more stable with the lowest percentage mass loss compared to the unmodified montmorillonite. The tripartite magnetic composite showed higher adsorption capacity. Adsorption was best described by the Freundlich isotherm model, which confirmed that the adsorption process was multilayer coverage unto the uneven surface of the adsorbents. Kinetic treatment of the adsorption data confirmed the the process followed a pseudo-second-order kinetic model and predominantly chemisorption process. The standard Gibb’s free energy computed for the adsorbents showed that the adsorption processes were favourably spontaneous with highly negative energy values of −336.70, −533.76 and −1438.38 KJ/mol, respectively, for the unmodified montmorillonite, doped titanium composite and the tripartite magnetic composite. It was observed that the addition of cationic aromatic moiety to the clay material increased pollutant-adsorbent interactions and improved adsorption capacity for micro-pollutants in a simulated industrial effluent.

Removal of diphenols using pine biochar. Kinetics, equilibrium, thermodynamics, and mechanism of uptake

Thermal pyrolysis synthesized activated biochar from the Pinus elliottii sawdust (PS) at 600° C. The obtained activated biochar (PB600) was used for the removal of three diphenols, catechol (CAT), resorcinol (RES), and hydroquinone (HYD), which are utilized mainly in different industries. The PB600 was characterized by several analytical techniques. The BET surface area of 1473 m2.g−1 and a total pore volume of 0.707 cm3 g−1 was obtained. The functional groups and amount of acidic and basic groups on the biochar were determined by FTIR and Bohem titration, respectively. From the isotherm studies, it was obtained that the maximum adsorption capacities (Qmax) based on the Liu isotherm model were 419.8 (CAT 45 °C), 263.8 (RES 40 °C), and 500.9 mg g−1 (HYD 25 °C). The values of thermodynamic parameters demonstrated that CAT, RES, and HYD adsorption processes were spontaneous, exothermic, and energetically favorable, and the magnitude of ΔH° was compatible with physisorption. The CAT, RES, and HYD adsorption mechanism onto the biochar is followed by porous filling, π-π interactions, and hydrogen bonds. Subsequently, PB600 biochar was employed as a potential adsorbent for treating simulated industrial effluents in a complex matrix simulating a real industrial effluent, and the overall removal attained up to 95.97 %. In concert with the experimental results, the electronic properties of the developed adsorption systems, including frontier molecular orbitals, charge density difference, and partial density of states, were studied by the density functional theory (DFT) approach to explore the mechanism of adsorption on the activated biochar surface.

Influence of pollutant concentration on the separation efficiency of chelating membranes for removing simultaneously metal ions and proteins from simulated industrial wastewater

AbstractBACKGROUNDA novel chelating membrane was fabricated for removing simultaneously metal ions (Cd2+, Pb2+ and Cu2+) and proteins (bovine serum albumin and lysozyme) from simulated industrial effluent. The purpose of the study was to investigate the influence of pollutant concentration on the separation efficiency of the chelating membrane for pollutants.RESULTS(i) The removal of metal ions mainly relies on the adsorption capacity of the chelating membrane, and seems to be independent of the concentration of protein. (ii) The retention of proteins depends mainly on their concentration in solution. (iii) When the wastewater contains high concentration of metal ions (C = 100 mg L−1) and low concentration of proteins (C = 10 mg L−1), the chelating membrane exhibits overall poor separation performance, with a low ion removal efficiency (55–70%) and a low protein rejection rate (ca 60%). (iv) When the wastewater contains low concentration of metal ions (C = 10 mg L−1) and high concentration of proteins (C = 100 mg L−1), the chelating membrane exhibits overall excellent separation performance, with ion removal rates of higher than 90% (except for Cd2+) and protein rejection rates of higher than 90%.CONCLUSIONSThe separation efficiency of the chelating membrane for metallic and organic pollutants greatly depends on the pollutant concentration in the wastewater. This study provides a theoretical basis for membrane technology for removing simultaneously heavy metals and organic pollutants in wastewater. © 2022 Society of Chemical Industry (SCI).

Ag nanoparticles anchored on NiO octahedrons (Ag/NiO composite): An efficient catalyst for reduction of nitro substituted phenols and colouring dyes

The development of an efficient sustainable catalyst for effective removal of hazardous chemicals, viz. nitrophenols and organic dyes, from wastewater is a challenging task. Herein, facile synthesis of Ag/NiO composites by anchoring Ag nanoparticles (NPs) on NiO octahedrons with different amounts of Ag NPs (AN-5% (5% Ag), AN-10% (10% Ag) and AN-15% (15% Ag)) has been demonstrated. SEM (scanning electron microscopic) and TEM (transmission electron spectroscopic) images ensured the proper anchoring of spherical Ag NPs (particle size = 16.54 ± 1.88 nm) on octahedron particles of NiO, which was also ensured by XPS (X-ray photoelectron spectroscopy) analysis. Moreover, the resulting composites have an average surface area (49–52 m2g‒1) and pore size (2.39–2.26 nm). All three synthesized Ag/NiO composites (100 μL) catalyzed the complete reduction of para-np (4-nitrophenol: 0.1587 mM) within 2–3 min in the presence of 0.04 M NaBH4. Among them, AN-5% has been chosen because of the lowest anchored Ag (5%) to obtain the optimized catalyst's amount (50 μL) and concentration of para-np (0.1587 mM). AN-5% also exhibited excellent catalytic activity towards different nitro substituted phenols, viz. ortho-np (2-nitrophenol), meta-np (3-nitrophenol), para-np (4-nitrophenol) and tri-np (2,4,6-trinitrophenol). AN-5% displayed ∼100% catalytic efficiency for reducing meta-np in 2 min with the apparent first order rate constant (kapp) and normalized rate constant (Knor) as 1.99 s−1 and 398.14 s−1 g−1, respectively. Additionally, AN-5% (29.41 μg mL−1) reduced >95% of the colouring dyes (10 ppm) such as CONG-R (congo red: 95% in 6 min), METH-O (methyl orange: 97.5% in 7 min), METH-B (methylene blue: 98.3% in 10 min) and RHOD-B (rhodamine B: 99.2% in 5 min). AN-5% not only demonstrated catalytic reduction towards individual pollutants, but also showed excellent activity for reduction of the mixtures of nitrophenols/dyes and for treatment of simulated industrial effluent samples (EFF1, EFF2) and a real industrial sample (textile dye-bath effluent). AN-5% can also be reused up to several cycles with almost same efficiency and followed the Langmuir-Hinshelwood apparent first order kinetics model.

A highly efficient nanoscale tapioca starch prepared by high‐speed jet for Cu2+ removal in simulated industrial effluent

AbstractBACKGROUNDNanoscale tapioca starch (NTS) was successfully developed by high‐speed jet in our previous study. In this study, the adsorption capacity of Cu2+ onto NTS was further discussed. The optimal adsorption conditions (pH, contact time, contact temperature, initial Cu2+ concentration, and adsorbent concentration), adsorption kinetics, isotherms, and thermodynamic were also evaluated.RESULTSThe results showed that NTS exhibited excellent performance in adsorption of Cu2+, with adsorption capacities of 122.31 mg g−1 for Cu2+ (pH 7, 0.04 g L−1, 0.2 g L−1, 313.15 K and 10 min). The pseudo‐second‐order and Langmuir isotherms models could be used to explain the adsorption kinetics and adsorption equilibrium, respectively. The thermodynamic results showed that the adsorption process was spontaneous and endothermic with an increase in entropy. Cu2+ was adsorbed onto NTS, which was confirmed by energy dispersive spectrometry analysis.CONCLUSIONThese findings indicated that NTS might be an effective, environment‐friendly and renewable bio‐resource adsorbent for removing heavy metals in industrial effluent. © 2021 Society of Chemical Industry

Preparation of activated carbon from black wattle bark waste and its application for phenol adsorption

Black wattle bark waste is generated in large amounts by tannin extraction industries, which leads to an environmental problem. In literature there are few reports about reusing this waste, mainly in adsorption processes. An activated carbon from black wattle bark waste was produced, characterized and applied for phenol adsorption. Activated carbon was produced under different carbonization and activation conditions, being characterized and applied as an adsorbent for phenol removal from aqueous solution. The results showed that phenol adsorption capacity increased with the increase of carbonization temperature and of activating agent ratio and, decreased with the increase of carbonization time. Activated carbon presented a micro/mesoporous structure and the surface area was 414.97 m2 g−1. FTIR analysis showed that lactone and quinone groups compose the surface chemistry of the activated carbon. The adsorption kinetics followed the pseudo-second order model. The Weber-Morris model showed that the adsorption occurred by film and intra-particle diffusion, and the increase in stirring rate led to an increase in film diffusion. Temperature increase led to an increase in phenol adsorption capacity, and the highest value was around 98.57 mg g−1, obtained at 55 °C. The Freundlich isotherm model was the more suitable to represent the equilibrium data. Thermodynamic study indicated that phenol adsorption onto the developed activated carbon was a spontaneous, favorable, endothermic and entropy-controlled process. The activated carbon can be used in two cycles with a slight decrease in the equilibrium adsorption capacity and presented a good efficiency to remove phenolic compounds in a simulated industrial effluent.

Thiol-ene synthesis of thioether/carboxyl-functionalized polymers for selective adsorption of silver (I) ions

In this study, a novel adsorbent (TCP) for the selective adsorption of Ag (I) was synthesized by thiol-ene polymerization of dimercaptosuccinic acid and 1,3,5-triallyl-1,3,5-triazine-2,4,6-trione. Element analysis, FT-IR and NMR spectroscopy confirmed that TCP was a functional-group-dense polymer with abundant thioether/carboxyl groups. The results of batch adsorption experiments revealed that the maximum adsorption capacity for Ag (I) by TCP at pH 4 was 5.2 mmol g−1, which was much higher than that at pH 2. Moreover, the adsorption isotherm of Ag (I) on TCP at pH 4 followed the Langmuir model better. However, the isothermal adsorption behavior at pH 2 fitted the Freundlich model well. The kinetic study demonstrated that both chemical adsorption and internal diffusion might be involved in the Ag (I) adsorption process. Furthermore, TCP showed much higher selectivity for Ag (I) in the presence of multiple interfering ions at pH 2 than that at pH 4. However, if the initial concentration of Ag (I) ions was high enough, TCP still exhibited good selectivity for Ag (I) in the presence of Cu (II) over a wide pH range: the selectivity coefficient (KAg/Cu) fluctuated between 40 and 60 in the pH range of 0.5–5. FT-IR spectroscopy and XPS analysis evidenced that the carboxyl and thioether groups in TCP could have synergistic effects on the adsorption of Ag (I), which might form five-membered or six-membered chelated rings, thereby inhibiting the combination of the carboxylic groups with other interfering ions. In addition, TCP showed high adsorption capacity and selectivity for Ag (I) in the treatment of simulated industrial effluent at pH 2.

Cellulose/polyaniline derivatives nanocomposites: Synthesis and their performance in removal of anionic dyes from simulated industrial effluents

ABSTRACTA series of cellulose/polyaniline derivatives [polyaniline (PANI), poly(N‐methylaniline) (PNMANI), and poly(N‐ethylaniline) (PNEANI)] nanocomposites were synthesized by in situ chemical oxidation polymerization method and successfully applied for removal of acid red 4 and direct red 23 dyes from simulated industrial effluents. The synthesized nanocomposites were analyzed using Fourier transform infrared and ultraviolet‐visible spectroscopies, thermogravimetric analysis and scanning electron microscope. The effect of some parameters including pH, adsorbent amount, and initial dyes concentrations on adsorption processes were evaluated. The maximum adsorption capacities (Qm) for the synthesized nanocomposites were calculated, and among them the Cell/PANI sample showed the highest Qm for both AR4 (117 mg g–1) and DR23 (56 mg g–1) dyes. The regeneration and reusability tests exhibited that the synthesized nanocomposites had the relatively good reusability after five repetitions of the adsorption–desorption cycles. According to results, we envision that these nanocomposites, especially Cell/PANI, find application for removal of anionic dyes from industrial effluents mainly due to their low production costs, high adsorption effectiveness, and relatively good reusability. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45352.

High performance and prospective application of xanthate-modified thiourea chitosan sponge-combined Pseudomonas putida and Talaromyces amestolkiae biomass for Pb(II) removal from wastewater

Biosorption using microbes has been proved to be an efficient technology to remove heavy metals from wastewater, whereas the imperfections in mechanical property and separation limit their practical application. In this study, Pseudomonas putida I3 and Talaromyces amestolkiae Pb respectively combined with xanthate-modified thiourea chitosan sponge (PXTCS and TXTCS) were synthesized to investigate the Pb(II) removal ability from solutions. The prepared biosorbents possessed a three-dimensional macroporous structure convenient for separation. Experimental data indicated their biosorption behaviors well followed the pseudo-second-order kinetics and Langmuir isotherm model. The maximum biosorption capacities of PXTCS and TXTCS were 232.03 and 241.61mgg−1 with 40% P. putida I3 and 15% T. amestolkiae Pb, respectively. For the effects of co-existing metal ions on Pb(II) biosorption, the promoting degree followed the sequence: Zn(II)>Na(I)≈K(I)>Ca(II)>Mg(II)≈Al(III)≫Cd(II)>Fe(III). Both prepared biosorbents were effective in removing heavy metals from simulated industrial effluents containing various trace-level heavy metals or high concentration Pb(II).

Radiation induced environmental remediation of Cr(VI) heavy metal in aerated neutral solution under simulated industrial effluent

Abstract Cr(VI) compounds are major water contaminants in most industrial effluents, due to their carcinogenicity, while Cr(III) is an important element for human metabolism. In a previous work, we showed that Cr(VI) was radiolytically reduced to Cr(III) by the CO2ˉ• radical at pH 3 N2O-saturated solution in the presence of formate. Here in the present work, this removal was investigated by steady state irradiation and pulse radiolysis in aerated solution at neutral pH, which is close to natural conditions in most wastewaters, where the reducing agent is the superoxide radical anion O2ˉ•. The degradation of Cr(VI) increased linearly with the absorbed dose and was significantly enhanced by the added formate but not by the radiolitically produced hydrogen peroxide at this pH. The rate constant for this reduction was found to be 1.28×108 M−1 s−1 and the absorption spectrum of Cr(V) transient species was obtained. A partial recovery of Cr(VI) is observed over a period of ca. 5 ms following a second order kinetics with a rate constant 8.0×106 M−1 s−1. These outcomes suggest that gamma-irradiation of Cr(VI)-contaminated wastewaters and industrial effluents in presence of formate can be simple, effective and economical means for the remediation of this major contaminant.

Activated carbon obtained from sapelli wood sawdust by microwave heating for o-cresol adsorption

Activated carbon (AC) was prepared from sapelli wood sawdust using a microwave heating process. The biomass was mixed with inorganic components (lime + ZnCl2 and FeCl3) to form a homogeneous paste. The AC samples are denoted as AC-1A (100 g sapelli wood sawdust + 20 g lime + 80 g ZnCl2), AC-2A (150 g sapelli wood sawdust + 20 g lime + 80 g ZnCl2), AC-1B (100 g sapelli wood sawdust + 20 g lime + 40 g ZnCl2 + 40 g FeCl3), and AC-2B (150 g sapelli wood sawdust + 20 g lime + 40 g ZnCl2 + 40 g FeCl3). The samples were placed in a microwave oven and pyrolyzed under nitrogen flow. To increase their porosity, the pyrolyzed samples were subjected to a leaching process (with 6 mol L−1 HCl) under reflux to eliminate inorganic components. Several analytical techniques such as Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and N2 isotherm and vapor adsorption analyses were performed to characterize the AC materials. The samples presented high Brunauer–Emmett–Teller (BET) surface areas, up to 941.08 m2 g−1 for AC-1A. The AC materials were tested for their o-cresol removal ability by determining the best fits to equilibrium and kinetic data using the Sips isotherm and fractional-order model, respectively. The maximum adsorption capacity of the AC samples as obtained from the Sips model was correlated with the surface area. The proposed adsorption mechanism suggests that hydrogen bonding, donor–acceptor complexation, and π–π interactions play key roles. The adsorbents were also tested for treatment of simulated industrial effluents, showing very good efficiency. Almost complete regeneration of the AC adsorbents was achieved using 10 % EtOH + 5 mol L−1 NaOH as eluent. These results demonstrate that sapelli wood sawdust is a promising precursor for preparation of AC to remove o-cresol from aqueous solution.

Performance Evaluation of a Bubble Column Photobioreactor for Carbon Dioxide Sequestration by Chlorella vulgaris

Biosequestration of carbon dioxide is a promising technique for global warming reduction. The present work evaluates the performance of a bubble column photobioreactor for simulated industrial effluent treatment using Chlorella vulgaris. C. vulgaris was cultivated under various conditions of initial size inoculum and initial carbon dioxide feed percentages. The maximum growth rate constant achieved was equal to 0.056 h−1 for the culture of an initial size of 0.01 g/L fed with 10% CO2. The mass of carbon fixed as a per cent of carbon sequestered was calculated for all cultures, and a maximum value of 40% was calculated for the culture of an initial size of 0.1 g/L fed with 5% CO2, indicating that not all carbon sequestered by the reactor is effectively fixed in biomass cells. The energy output (calculated as the higher heating value of produces biomass) as a per cent of light energy input was calculated to account for the energetic performance of the reactor, and the maximum calculated per cent was equal to 12.21% achieved for the culture of an initial size of 0.1 g/L fed with 5% CO2. Biomass subjected to a 16:8 and a 12:12 light/dark cycle yielded carbon fixation rate, which represents 86 and 18.8% of that obtained under continuous illumination respectively.

An electroanalytical approach for evaluation of biochar adsorption characteristics and its application for Lead and Cadmium determination

This work describes for first time the use of electroanalytical techniques for evaluation of adsorptive proprieties of biochar using it as electrode modifier and its application for preconcentration and determination of Lead(II) and Cadmium(II) under differential pulse adsorptive voltammetric conditions (DPAdSV). Samples of biochars were obtained from castor oil cake using a predefined set of experimental conditions varying the heating rate (V), final temperature (T) and warm-up period (P) and subsequently used for carbon paste modified electrode (CPME) preparation. The proposed method was applied for Lead(II) and Cadmium(II) determination in spiked simulated industrial effluents and the limit of detection obtained for both metals were adequated for determination of these evaluated ions taking into account the limits established by Brazilian legislation. For all samples analyzed, recoveries ranged from 95% to 104% were obtained and no significative interferences were observed for common cations in water samples.

Selective sorption and preconcentration of tartaric acid using a copper(II)-bound polymeric ligand exchanger

Abstract The current study reports a potential process to selectively separate and preconcentrate tartaric acid from its simulated industrial effluent. It was achieved by sorption onto a tailored polymeric ligand exchanger. The polymeric ligand exchanger is essentially a copper(II)-bound specialty chelating polymer (denoted D-Cu). Effect of solution pH and competing sulfate on tartaric acid sorption onto D-Cu was also included in the study. Compared to a weakly basic anion exchanger D-301, D-Cu exhibits more favorable sorption of tartaric acid from aqueous media coexisting with Na 2 SO 4 at a high level. The exhausted D-Cu was amenable to an entire regeneration by the diluted NaCl solution. Results of column sorption tests further demonstrated the feasibility of D-Cu for selective separation and preconcentration of tartaric acid from the simulated wastewater for its further recovery.

Application of the electron-beam treatment for Ca, Si, P, Al, Fe, Cr, Zn, Co, As, Se, Cd and Hg removal in the simulated and actual industrial effluents

The removal of Ca, Si, P, Al, Fe, Cr, Zn, Co, As, Se, Cd and Hg was determined in the simulated and actual industrial effluents using electron-beam treatment. The actual effluents gave the following results: a removal of ca. 80% for Ca and P with 20 kGy irradiation doses; more than 96% for Al and Si with 100 kGy; more than 99% for Ca, Fe, Zn, Cr and Co with 200 kGy and Hg showed a 71.0% removal with 500 kGy. In the simulated industrial effluent solution, As and Hg showed 92.5% and 99% removal with 500 and 100 kGy irradiation doses, respectively. Se and Cd showed a 99.6% and 44.0% removal with 500 kGy. HCOONa solution was added for Hg and As removal, and irradiation process was done in the oxidant atmosphere.