Muhammad Asif Hanif

Kinetic and thermodynamic aspects of Cu(II) and Cr(III) removal from aqueous solutions using rose waste biomass.

Distillation waste of rose petals was used to remove Cu(II) and Cr(III) from aqueous solutions. The results demonstrated the dependency of metal sorption on pH, sorbent dose, sorbent size, initial bulk concentration, time and temperature. A dosage of 1g/L of rose waste biomass was found to be effective for maximum uptake of Cu(II) and Cr(III). Optimum sorption temperature and pH for Cu(II) and Cr(III) were 303+/-1K and 5, respectively. The Freundlich regression model and pseudo-second-order kinetic model were resulted in high correlation coefficients and described well the sorption of Cu(II) and Cr(III) on rose waste biomass. At equilibrium q(max) (mg/g) of Cu(II) and Cr(III) was 55.79 and 67.34, respectively. The free energy change (DeltaG degrees ) for Cu(II) and Cr(III) sorption process was found to be -0.829 kJ/mol and -1.85 kJ/mol, respectively, which indicates the spontaneous nature of sorption process. Other thermodynamic parameters such as entropy change (DeltaS degrees ), enthalpy (DeltaH degrees )and activation energy (DeltaE) were found to be 0.604 J mol(-1)K(-1), -186.95 kJ/mol and 68.53 kJ/mol, respectively for Cu(II) and 0.397 J mol(-1)K(-1), -119.79 kJ/mol and 114.45 kJ/mol, respectively for Cr(III). The main novelty of this work was the determination of shortest possible sorption time for Cu(II) and Cr(III) in comparison to earlier studies. Almost over 98% of Cu(II) and Cr(III) were removed in only first 20 min at an initial concentration of 100 mg/L.

Pb(II) biosorption from hazardous aqueous streams using Gossypium hirsutum (Cotton) waste biomass.

Studies on the biosorptive ability of Gossypium hirsutum (Cotton) waste biomass outlined that smaller size of biosorbent (0.355mm), higher biomass dose (0.20g), 5 pH and 100mg/L initial Pb(II) concentration were more suitable for enhanced Pb(II) biosorption from aqueous medium. The Langmuir isotherm model and pseudo second order kinetic model fitted well to the data of Pb(II) biosorption. Highly negative magnitude of Gibbs free energy (DeltaG degrees ) indicated that the process was spontaneous in nature. In addition to this surface coverage and distribution coefficient values of Pb(II) biosorption process were also determined. At optimized conditions Pb(II) uptake was more rapid in case of industrial effluents in comparison to synthetic solutions. FTIR spectroscopic analysis revealed that the main functional groups involved in the uptake of Pb(II) on the surface of G. hirsutum biomass were carboxyl, carbonyl, amino and alcoholic.

Kinetic and Equilibrium Modeling of Pb(II) and Co(II) Sorption onto Rose Waste Biomass

Abstract An attempt was made to assess the biosorption potential of rose waste biomass for the removal of Pb(II) and Co(II) ions from synthetic effluents. Biosorption of heavy metal ions (>90%) reached equilibrium in 30 min. Maximum removal of Pb(II) and Co(II) occurred at pH 5 and 6 respectively. The biosorbent dose for efficient uptake of Pb(II) and Co(II) was 0.5 g/L for both metals. The biosorbent size affected the Pb(II) and Co(II) biosorption rate and capacity. Rose waste biomass was found effective for Pb(II) and Co(II) removal from synthetic effluents in the concentration range 10–640 mg/L. Equilibrium sorption studies showed that the extent of Pb(II) and Co(II) uptake by the rose waste biomass was better described by the Langmuir isotherm in comparison to the Freundlich model. The uptake capacities of the two metal ions were 156 and 27.15 mg/g for Pb(II) and Co(II) respectively.

KINETIC AND EQUILIBRIUM STUDIES OF CR(III) AND CR(VI) SORPTION FROM AQUEOUS SOLUTION USING ROSA GRUSS AN TEPLITZ (RED ROSE) WASTE BIOMASS

The biosorption of Cr(III) and Cr(VI) from synthetic solution using dried untreated and pretreated Rosa gruss an teplitz waste biomass was evaluated in this study. The results showed that initial pH, biosorbent dose, sorbent particle size, initial metal concentration, time and temperature affected chromium uptake capacity of rose biomass. The effect of twenty different pretreatments including gaseous and other reagents on Cr(III) and Cr(VI) uptake capacity of Rosa gruss an teplitz waste biomass was comprehensively described. Uptake capacity of Rosa gruss an teplitz waste biomass was significantly affected after pretreatment. The metal uptake capacity of biomass was not only found related to nature of pretreatment but also found strongly related to oxidation state of chromium. The estimation of the correlation coefficients for Cr(VI) showed that the experimental data fit better to Freundlich model. The Langmuir isotherm provided the best correlation for Cr(III) onto the rose waste biomass. The biosorption phenomenon was dependent on the temperature with maximum adsorption at 30˚C. Biosorption of Cr(III) and Cr(VI) ions on to biomass followed pseudo 2nd order adsorption kinetic model. The results confirmed that rose waste biomass is a potential biomaterial to remove Cr(III) and Cr(VI) ions with a high biosorption capacity 45.03 mg/g and 48.75 mg/g for Cr(III) and Cr(VI) respectively.

Removal of Cu(II) and Zn(II) Using Lignocellulosic Fiber Derived from Citrus reticulata (Kinnow) Waste Biomass

Abstract The biosorption of Cu(II) and Zn(II) using dried untreated and pretreated Citrus reticulata waste biomass were evaluated. The Cu(II) and Zn(II) sorption were found to be dependent on the solution pH, the biosorbent dose, the biosorbent particle size, the shaking speed, the temperature, the initial metal ions (800 mg/L), and the contact time. Twenty-eight physical and chemical pretreatments of Citrus reticulata waste biomass were evaluated for the sorption of Cu(II) and Zn(II) from aqueous solutions. The results indicated that biomass pretreated with sulphuric acid and EDTA had maximum Cu(II) and Zn(II) uptake capacity of 87.14 mg/g and 86.4 mg/g respectively. Moreover, the Langmuir isotherm model fitted well than the Freundlich model with R 2 > 0.95 for both metal ions. The sorption of Cu(II) and Zn(II) occurred rapidly in the first 120 min and the equilibrium was reached in 240 min. FTIR and SEM studies were also carried out to investigate functional groups present in the biomass and the surface morphological changes of biomass.

Biosynthesis of essential oils in aromatic plants: A review

ABSTRACT In aromatic plants species, biosynthesis of essential oils occurs through two complex natural biochemical pathways involving different enzymatic reactions. Isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) are the universal precursors of essential oil biosynthesis and are produced by the cytosolic enzymatic MVA (mevalonic acid) pathway or by plastidic and enzymatic 1-deoxy-d-xylolose-5-phosphate (DXP) pathway, also called the 2-C-methylerythritol-4-phosphate (MEP) pathway. In the particular plant cell part, prenyl diphosphate synthases condense isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) further to form prenyl diphosphates, which are used as substrates for geranyl diphosphate (GPP; C10) or for fernesyl diphosphate (FPP; C15). Essential oils are final terpenoid products and are formed by a huge group of enzymes known as terpene synthases (TPS). Essential oils are important secondary metabolites of plants and have been used not only in different industries but also in ethnobotanical medicines for centuries. Hence, considerable research has been undertaken to understand the essential oil biosynthetic pathways. This review will be a valuable source of information in the field of natural products, as we give detailed insights about biosynthesis of essential oils in plants and thus indicate also new unexplored horizons for further research.

Synthesis, urease inhibition, antioxidant, antibacterial, and molecular docking studies of 1,3,4-oxadiazole derivatives.

A series of eighteen 1,3,4-oxadiazole derivatives have been synthesized by treating aromatic acid hydrazides with carbon disulfide in ethanolic potassium hydroxide yielding potassium salts of 1,3,4-oxadiazoles. Upon neutralization with 1 N hydrochloric acid yielded crude crystals of 1,3,4-oxadiazoles, which were purified by recrystallization in boiling methanol. The synthesized 1,3,4-oxadiazoles derivatives were evaluated in vitro for their urease inhibitory activities, most of the investigated compounds were potent inhibitors of Jack bean urease. The molecular docking studies were performed by docking them into the crystal structure of Jack bean urease to observe the mode of interaction of synthesized compounds. The synthesized compounds were also tested for antibacterial and antioxidant activities and some derivatives exhibited very promising results.

Biosorption of Cu(II) ions from aqueous effluents by blackgram bran (BGB).

Biosorption of Cu(II) ions onto blackgram bran (BGB) waste biomass in a well stirred batch system was investigated and optimum conditions were determined. The maximum Cu(II) uptake capacity of BGB was 107.65 mg L(-1) at pH 5, biosorbent dose 0.025 g/100mL, biosorbent particle size <0.250 mm at an initial metal concentration of 50 mg L(-1) achieved after equilibrium time of 480 min. The equilibrium data fitted very well to Langmuir isotherm model as compared to the isothermal model of Freundlich. The pseudo 1st and 2nd order kinetic models were used to describe the kinetic data. The experimental data fitted well to 2nd order kinetic model. Due to its outstanding Cu(II) ions uptake capacity, BGB biomass proved to be an excellent material of bioorigin for accumulating Cu(II) ions from aqueous solutions.

Remediation of heavy metals using easily cultivable, fast growing, and highly accumulating white rot fungi from hazardous aqueous streams

There has been little investigation into the use of easily cultivable, fast growing, and highly accumulating live white rot fungi (WRF) for the remediation of heavy metal ions contamination. In this regard, the present study was planned to assess the Cu(II), Pb(II), Cr(III), and Cr (VI) remediation potential of live immobilized Pleutrotus sajor-caju, Agaricus bitorquis, and Ganoderma lucidum from aqueous solutions as well as real hazardous effluents. Immobilized A. bitorquis had higher heavy metal ions remediation potential as compared to other two strains. The effect of pH, dose, initial metal concentration, time, temperature, etc. on bioremediation potential of WRF were investigated in a batch system. The maximum potential of live immobilized A. bitorquis for remediation of Cr(III), Pb(II), Cr(VI), and Cu(II) was 226.6, 208.5, 207.3, and 205.1mg/g, respectively. Sulfuric acid (0.1M) was found to be the best desorbing agent. Immobilized A. bitorquis remediated heavy metal ions from textile industry wastewater in the following priority order: Cr(III)>Pb(II)>Cr(VI)>Cu(II).

Removal of zirconium from aqueous solution by Ganoderma lucidum: biosorption and bioremediation studies

AbstractThe development of nuclear science and technology, especially the wide applications of nuclear power, poses a major environmental threat that needs to be remediated. The present study reports the ability of live and dead mycelia of Ganoderma lucidum to remove Zr(IV) ions from aqueous solutions in batch system. The biosorption characteristics of G. lucidum for Zr(IV) ions were evaluated as a function of medium pH, biomass dosage, contact time, initial zirconium concentration and temperature. Maximum zirconium uptake (142.5 mg/g) was observed at pH 3.5. Increase in biomass dosage did not increase the biosorption capacity. The zirconium biosorption was rapid, with more than 74% of the total biosorption taking place within 15 min and equilibrium was attained after 240 min. The Zr(IV) biosorption process could be well defined by the Langmuir isotherm. The kinetic data fitted the pseudo-second-order kinetic model. A dilute solution of sulphuric acid (0.1 N) was found to be the most effective desorbing a...