Coir Pith Carbon Research Articles

Treatment of 2,4,6-trichlorophenol using agricultural by-products

This research discusses adsorption of 2,4,6-trichlorophenol (TCP) using coir pith carbon produced from agricultural by-products. Batch mode studies investigated the essential adsorption aspects like initial adsorbate concentration, dosage of adsorbent, varying pH and temperature. The mechanism of kinetic adsorption was rapid, attaining equilibrium at 50 and 110 min for concentrations of TCP (10–40 mg/L). Experimental kinetic data revealed excellent match for second order kinetic. Only Freundlich followed the isothermic adsorption data and pH 2.0 was appropriate for TCP adsorption. Desorption experiments have shown that chemical adsorption plays a significant role that has also been supported by studies of thermodynamic factors like standard enthalpy, entropy and free energy.

Copper biosorption using local Iraqi natural agents

Industrial effluents loaded with heavy metals are a cause of hazards to the humans and other forms of life. Conventional approaches, such as electroplating, ion exchange, and membrane processes, are used for removal of copper, cadmium, and lead and are often cost prohibitive with low efficiency at low metal ion concentration. Biosorption can be considered as an option which has been proven as more efficient and economical for removing the mentioned metal ions. Biosorbents used are fungi, yeasts, oil palm shells, coir pith carbon, peanut husks, and olive pulp. Recently, low cost and natural products have also been researched as biosorbent. This paper presents an attempt of the potential use of Iraqi date pits and Al-Khriet (i.e. substances locally available in Iraq and found in the legs of Typha domingensis) as basements. The important factors studied which affect the removal of copper ion are solution pH value (4–8), adsorbent dosage (0.5–2 g), contact time [((1/2–4) h) for Al-Khriet and (1/2–24) h for date pits]; and (50–200) ppm copper ion concentration. The results showed that it is possible to remove 96% of Cu+2 after 4 h contact time using Al-Khriet, and 84% of Cu+2 after 24 h contact time using date pits. The kinetic data agree with a pseudo-second-order equation. Isotherm analysis showed that the adsorption process describes Langmuir better than the Freundlich.

Kinetics and isotherm studies for the adsorption of phenol using low cost micro porous ZnCl2 activated coir pith carbon

In the present study, the potential of ZnCl2 activated coir pith carbon for adsorption of phenol from aqueous solution was investigated. Batch kinetics and isotherm studies were carried out to evaluate the effects of contact time, initial concentration, adsorbent dose, pH, and temperature. Adsorption kinetics was tested for first order, second order, and Bangham’s model and rate constants of kinetic models were evaluated. Equilibrium isotherms for the adsorption of phenol were analysed by Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherm models. The Langmuir adsorption capacity, Q0, was found to be 92·58 mg g−1 of the adsorbent. pH effect showed that physical adsorption might be involved in the adsorption process. Thermodynamic studies revealed that the adsorption of phenol by activated carbon was an endothermic process. The negative value of ΔG0 indicated the spontaneity of the adsorption process. Removal of phenol from synthetic wastewater was also tested. This study showed that ZnCl2 activated coir pith carbon could be used as an efficient adsorbent material for the removal of phenol from water.

ZnCl2-Modified Activated Carbon from Biomass Coir Pith for the Removal of 2-Chlorophenol by Adsorption Process

ABSTRACT Coir pith, a waste biomass, from coconut coir industry was used to prepare activated carbon with ZnCl2 and employed for the removal of 2-chlorophenol (2-CP) from aqueous solution and wastewater. Zinc chloride–activated coir pith carbon (ZnCPC) was prepared by mixing coir pith with ZnCl2 in the ratio 2:1 and carbonized at 700°C for 1 h. ZnCPC was characterized using standard physicochemical methods, Brunaver, Emmett, and Teller (BET) surface area, and scanning electron microscopy (SEM) studies. Batch mode adsorption studies were carried out to evaluate the effect of contact time, initial concentration, adsorbent dose, pH, and temperature. The Langmuir adsorption capacity Q 0 was found to be 149.3 mg g−1. Kinetic studies showed that the adsorption obeyed second-order and Bangham's model. Equilibrium adsorption data fit better into Langmuir, Freundlich, and D-R isotherms. pH effect and desorption studies showed that ion-exchange mechanism was involved in the adsorption process. Effect of temperature was not significant. Quantitative removal of 2-CP from synthetic wastewater was also achieved. ZnCPC is economically effective compared to commercial activated carbon, because the raw material is abundantly and freely available and it can be used effectively in the treatment of water contaminated with 2-CP.

Kinetics and isotherm studies for the adsorption of phenol using low cost micro porous ZnCl2 activated coir pith carbonA paper submitted to the Journal of Environmental Engineering and Science.

In the present study, the potential of ZnCl2 activated coir pith carbon for adsorption of phenol from aqueous solution was investigated. Batch kinetics and isotherm studies were carried out to evaluate the effects of contact time, initial concentration, adsorbent dose, pH, and temperature. Adsorption kinetics was tested for first order, second order, and Bangham’s model and rate constants of kinetic models were evaluated. Equilibrium isotherms for the adsorption of phenol were analysed by Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherm models. The Langmuir adsorption capacity, Q0, was found to be 92.58 mg g–1 of the adsorbent. pH effect showed that physical adsorption might be involved in the adsorption process. Thermodynamic studies revealed that the adsorption of phenol by activated carbon was an endothermic process. The negative value of ΔG0 indicated the spontaneity of the adsorption process. Removal of phenol from synthetic wastewater was also tested. This study showed that ZnCl2 activated coir pith carbon could be used as an efficient adsorbent material for the removal of phenol from water.

Application of coconut coir pith for the removal of sulfate and other anions from water

Activated carbon was developed from coconut coir pith using ZnCl 2 and investigated to assess the possible use of this adsorbent for the removal of sulfate from water. The influence of various parameters such as agitation time, sulfate concentration, adsorbent dose, pH and temperature has been studied. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. The Langmuir adsorption capacity (Q o) was found to be 4.9 mg/g. Adsorption followed second-order rate kinetics. The per cent adsorption was maximum in the pH range 3.0–9.0 (90–54%) and desorption was higher at pH 2.0 (58–74%) and pH 11.0 (83–97%) for different concentrations of sulfate used in this study. pH effect and desorption studies showed that ion exchange and chemisorption mechanisms were involved in the adsorption process. ΔG 0 was found to be –25.8, –26.2, –27.5 and –28.8 kJ/mol at 35, 40, 50 and 60EC, respectively. ΔS 0 and ΔH 0 of adsorption were found to be 132.7 J/K/mol and 15.4 kJ/mol, respectively. Effects of foreign ions on the adsorption of sulfate have been investigated. Removal of sulfate from synthetic ground water was tested. The Langmuir adsorption capacity of other anions such as nitrate, phosphate, vanadate, molybdate, thiocyanate and chromate was also investigated. Results showed that ZnCl 2 activated coir pith carbon was effective for the removal of sulfate and other anions from water.

Capacity of activated carbon in the removal of acid brilliant blue: Determination of equilibrium and kinetic model parameters

Abstract The adsorption of acid brilliant blue onto thermally activated coir pith carbon in aqueous solution was studied in a batch system with respect to contact time, pH, and temperature. Acidic pH was favorable for the adsorption of this dye. The surface characterization of thermally activated coir pith carbon was performed using the FT-IR technique. Kinetic studies showed that the adsorption of dye on coir pith carbon was a gradual process. Lagergren-first-order, second-order, intra-particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubinin–Radushkevich and Tempkin isotherms. The adsorption capacity was found to be 15.24 mg/g by Langmuir isotherm. The pH effect and desorption studies suggest that chemisorption might be the major mode of the adsorption process. The change is entropy (Δ S °) and heat of adsorption (Δ H °) of coir pith carbon was estimated as185.45 J/(mol K) and 48.02 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous nature of adsorption on acid brilliant blue on coir pith carbon.

Recycling coir pith, an agricultural solid waste, for the removal of procion orange from wastewater

Batch adsorption experiments were carried out for the removal of procion orange from its aqueous solution using coir pith carbon. This study examines adsorption kinetic parameters on coir pith carbon. The effect of process parameters like contact time, concentration of dye, temperature and pH on the extent of procion orange adsorption from solution has been investigated. In order to develop an effective and accurate design model for removal of dye, adsorption kinetics and equilibrium data are essential basic requirements. Kinetic study showed that the adsorption of dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, Bangham's and intra-particle diffusion model were used to fit the experimental data. Results of the kinetic studies show that the adsorption reaction is second-order kinetic model with respect to dye solution concentration. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Dubnin–Radushkevich, and Tempkin isotherms. The adsorption equilibrium data obeyed Langmuir, Dubnin–Radushkevich, and Tempkin isotherms. The adsorption capacity was found to be 2.6 mg/g of carbon. Increase of temperature increased adsorption. Acidic pH was favorable for the adsorption of dye. Studies on pH effect and desorption show that chemisorption seems to play a major role in the adsorption process.

Removal of chromium(VI) by ZnCl2 activated coir pith carbon

The adsorption of chromium(VI) onto ZnCl2 activated carbon developed from coir pith was investigated to assess the possible use of this adsorbent. The influence of contact time, adsorbent dose, Cr(VI) concentration, pH and temperature were investigated. The two theoretical adsorption isotherms, namely, Langmuir and Freundlich were used to describe the experimental results. The Langmuir adsorption capacity (Q 0) was found to be 120.5 mg Cr(VI) per g of the adsorbent. The adsorption followed the second-order kinetics and was found to be maximum at pH 2.0. The pH effect and the desorption studies showed that ion exchange mechanism might be involved in the adsorption process. The effects of foreign ions such as chloride, sulphate, phosphate, selenite, molybdate, nitrate and perchlorate on the removal of Cr(VI) have been investigated. The removal of Cr(VI) from synthetic ground water was also tested. The results show that ZnCl2 activated coir pith carbon is effective for the removal of Cr(VI) from water.

Removal and recovery of vanadium(V) by adsorption onto ZnCl2 activated carbon: Kinetics and isotherms

Adsorption of vanadium(V) from aqueous solution onto ZnCl2 activated carbon developed from coconut coir pith was investigated to assess the possible use of this adsorbent. The influence of various parameters such as agitation time, vanadium concentration, adsorbent dose, pH and temperature has been studied. First, second order, Elovich and Bangham’s models were used to study the adsorption kinetics. The adsorption system follows second order and Bangham’s kinetic models. Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms have been employed to analyze the adsorption equilibrium data. Equilibrium adsorption data followed all the four isotherms—Langmuir, Freundlich, D-R and Temkin. The Langmuir adsorption capacity (Q 0) was found to be 24.9 mg g− 1 of the adsorbent. The per cent adsorption was maximum in the pH range 4.0–9.0. The pH effect and desorption studies showed that ion exchange mechanism might be involved in the adsorption process. Thermodynamic parameters such as ΔG 0, ΔH 0 and ΔS 0 for the adsorption were evaluated. Effect of competitive anions in the aqueous solution such as PO4 3 −, SO4 2−, ClO4 −, MoO4 2−, SeO3 2−, NO3 − and Cl− was examined. SEM and FTIR were used to study the surface of vanadium(V) loaded ZnCl2 activated carbon. Removal of vanadium(V) from synthetic ground water was also tested. Results show that ZnCl2 activated coir pith carbon is effective for the removal of vanadium(V) from water.

Experimental and kinetic studies on methylene blue adsorption by coir pith carbon

Varying the parameters such as agitation time, dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of dye was removed with decrease in the initial concentration of dye and increase in amount of adsorbent used. Kinetic study showed that the adsorption of dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin-Radushkevich, and Tempkin isotherm. The adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250-500 microm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the adsorption process. The change in entropy (DeltaS0) and heat of adsorption (DeltaH0) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous adsorption of methylene blue on coir pith carbon.

Recycling of agricultural solid waste, coir pith: Removal of anions, heavy metals, organics and dyes from water by adsorption onto ZnCl 2 activated coir pith carbon

The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl 2 activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as resorcinol, 4-nitrophenol, catechol, bisphenol A, 2-aminophenol, quinol, O-cresol, phenol and 2-chlorophenol has also been investigated. Uptake of acidic dyes such as acid brilliant blue, acid violet, basic dyes such as methylene blue, rhodamine B, direct dyes such as direct red 12B, congo red and reactive dyes such as procion red, procion orange were also examined to assess the possible use of the adsorbent for the treatment of contaminated ground water. Favorable conditions for maximum removal of all adsorbates at the adsorbate concentration of 20 mg/L were used. Results show that ZnCl 2 activated coir pith carbon is effective for the removal of toxic pollutants from water.

IR, XRD and SEM studies on the mechanism of adsorption of dyes and phenols by coir pith carbon from aqueous phase

Adsorption interactions of dye, phenol and chlorophenol onto coir pith carbon from aqueous solution were investigated using FT-IR Spectroscopy, Scanning Electron Microscopy (SEM), and X-ray diffraction techniques. IR studies revealed the participation of some of the surface functional groups in the adsorption mechanism, SEM revealed the morphological observations of the unloaded adsorbent and thereby changes in the adsorbed carbon. X-ray diffraction studies exhibited a decrease in crystalline nature of the loaded adsorbent compared with unloaded adsorbent.

Removal of molybdate from water by adsorption onto ZnCl 2 activated coir pith carbon

Removal and recovery of molybdate from aqueous solution was investigated using ZnCl 2 activated carbon developed from coir pith. Studies were conducted to delineate the effects of contact time, adsorbent dose, molybdate concentration, pH and temperature. Two theoretical adsorption isotherms, namely, Langmuir and Freundlich were used to describe the experimental results. The Langmuir adsorption capacity ( Q 0) was found to be 18.9 mg molybdate/g of the adsorbent. Adsorption followed second order kinetics. Studies were performed at different pH values to find out the pH at which maximum adsorption occurred. The pH effect and desorption studies showed that ion exchange and chemisorption mechanism were involved in the adsorption process. Thermodynamic parameters such as Δ G 0, Δ H 0 and Δ S 0 for the adsorption were evaluated. Effect of foreign ions on adsorption of molybdate has been examined. The results showed that ZnCl 2 activated coir pith carbon was effective for the removal and recovery of molybdate from water.

Removal of Heavy Metals from Wastewater by Adsorption on Coir Pith Activated Carbon

ABSTRACTThe activated carbon prepared from coconut coir pith by potassium hydroxide activation was found to exhibit remarkable adsorption capacity for cadmium, copper, and zinc. Batch equilibrium tests showed that the extent of metal removal was found to be dependent on initial concentration, contact time, pH, and carbon dose. It was found that at pH values below 3, the adsorption of metal ions was very less and was effective above pH 6. The metal ion sorption was found to follow the Freundlich model. The kinetics of adsorption of metal ions followed 1st order. The agglomerated coir pith carbon was evaluated for the effect of flow rate and bed depth in column experiments. Linear relationships between bed depth and service time were obtained for all the metal ions by performing bed-depth service time (BDST) analysis. The adsorbed metal ions could be quantitatively recovered by using 1.0 M HCl, and the capacity of carbon remained unaffected when put to repeated use for the removal of metal ions from aqueous solutions. The efficiency of carbon when applied to industrial effluents was found to be superior in removal of metal ions compared with the commercial ones.

Equilibrium and kinetic studies of adsorption of phosphate onto ZnCl2 activated coir pith carbon

Phosphate removal from aqueous solution was investigated using ZnCl(2)-activated carbon developed from coir pith, an agricultural solid waste. Studies were conducted to delineate the effect of contact time, adsorbent dose, phosphate concentration, pH, and temperature. The adsorption equilibrium data followed both Langmuir and Freundlich isotherms. Langmuir adsorption capacity was found to be 5.1 mg/g. Adsorption followed second-order kinetics. The removal was maximum in the pH range 3-10. pH effect and desorption studies showed that adsorption occurred by both ion exchange and chemisorption mechanisms. Adsorption was found to be spontaneous and endothermic. Effect of foreign ions on adsorption shows that perchlorate, sulfate, and selenite decreased the percent removal of phosphate.

Adsorptive removal of 2-chlorophenol by low-cost coir pith carbon

Adsorption of 2-chlorophenol (2-CP) by coir pith carbon was carried out by varying the parameters such as agitation time, 2-CP concentration, adsorbent dose, pH and temperature. Adsorption equilibrium reached at 40, 60, 80 and 100 min for 2-CP concentration of 10, 20, 30 and 40 mg/l, respectively. Adsorption followed second-order kinetics. The adsorption equilibrium data obeyed Freundlich isotherm. Acidic pH was favorable for the adsorption of 2-CP. Desorption studies showed that chemisorption plays a major role in the adsorption process.

Removal of Congo Red from water by adsorption onto activated carbon prepared from coir pith, an agricultural solid waste

The adsorption of Congo Red by coir pith carbon was carried out by varying the parameters such as agitation time, dye concentration, adsorbent dose, pH and temperature. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. Adsorption followed second-order rate kinetics. The adsorption capacity was found to be 6.7 mg dye per g of the adsorbent. Acidic pH was favourable for the adsorption of Congo Red. Desorption studies suggest that chemisorption might be the major mode of adsorption.

Uptake of dyes by a promising locally available agricultural solid waste: coir pith

The adsorption of rhodamine-B and acid violet by coir pith carbon was carried out by varying the parameters such as agitation time, dye concentration, adsorbent dose and pH. The adsorption followed both Langmuir and Freundlich isotherms. The adsorption capacity was found to be 2.56 mg and 8.06 mg dye per g of the adsorbent for rhodamine-B and acid violet, respectively. Adsorption of dyes followed first order rate kinetics. Acidic pH was favorable for the adsorption of acid violet and alkaline pH was favorable to rhodamine-B. Desorption studies showed that alkaline pH was favorable for the desorption of acid violet and acidic pH was favorable for the desorption of rhodamine-B.

Agricutural By-Product as Metal Adsorbent: Sorption of Lead(II) from Aqueous Solution onto Coirpith Carbon

Activated carbon prepared from coirpith waste was used for the adsorptive removal of Pb(II) from aqueous solution. Parameters such as agitation time, metal ion concentration, adsorbent dose and pH were studied. Adsorption equilibrium was reached in 30 min for solution containing 25 and 50 mg l−1 and 40 min for solution containing 75 and 100 mg l−1 Pb(II), respectively. Adsorption parameters were determined using both Langmuir and Freundlich models. The adsorption capacity was 263 mg g−1. Pb(II) removal increased with increased pH from 2 to 4 and remained constant up to pH 10. Desorption studies were also carried out with dilute hydrochloric acid to recover both carbon and Pb(II). As the raw material for the preparation of activated carbon is discarded as waste during coir processing, the production of this carbon is expected to be economically feasible.