Advanced microbial fuel cell for waste water treatment-a review.

Petroleum, coal, and natural gas reservoir were depleting continuously due to an increase in industrialization, which enforced study to identify alternative sources. The next option is the renewable resources which are most important for energy purpose coupled with environmental problem reduction. Microbial fuel cells (MFCs) have become a promising approach to generate cleaner and more sustainable electrical energy. The involvement of various disciplines had been contributing to enhancing the performance of the MFCs. This review covers the performance of MFC along with different wastewater as a substrate in terms of treatment efficiencies as well as for energy generation. Apart from this, effect of various parameters and use of different nanomaterials for performance of MFC were also studied. From the current study, it proves that the use of microbial fuel cell along with the use of nanomaterials could be the waste and energy-related problem-solving approach. MFC could be better in performances based on optimized process parameters for handling any wastewater from industrial process.

Experimental investigations of arsenic adsorption from contaminated water using chemically activated hematite (Fe2O3) iron ore.

Indigenous hematite iron ore was chemically activated as a function of various hydrogen peroxide concentrations (0.5, 1, 1.5, and 2.0 M), activation time, and iron ore size. Adsorption potential was evaluated at various initial arsenic concentrations, contact time, adsorbent dose, and particle size. Maximum 95% removal efficiency was achieved at 600-µm size of iron ore, activated with 0.5 M concentration of hydrogen peroxide at 24 h of activation time. The experimental data were further evaluated through Langmuir and Freundlich isotherms. The maximum 14.46 mg/g of adsorption capacity was observed through Langmuir isotherm. Moreover, adsorption kinetics was evaluated using pseudo-first-order and pseudo-second-order kinetics, and the intra-particle diffusion model. The kinetics of arsenic adsorption was best described by using the pseudo-first-order kinetics with a kinetic rate of 0.621 min-1. The hematite iron ore before and after arsenic adsorption was characterized by XRD, SEM, and EDX.

Experimental study and dynamic simulation of melanoidin adsorption from distillery effluent.

This work aims to utilize fly ash from a thermal power station for melanoidin reduction from distillery effluent by adsorption. To accomplish this, coal fly ash was modified through chemical treatment and was then tested for melanoidin adsorption as a function of various melanoidin concentrations, contact time, and pH. The specific novelty of this study is the evaluation of coal fly ash as a low-cost adsorbent for melanoidin removal. Furthermore, the simulation study was carried out using Aspen ADSIM software in order to optimize the commercial usage of the prepared adsorbent. The main results achieved include the maximum removal efficiency of 84% which was reached at initial melanoidin concentration of 1100 mg L-1 (5% dilution), pH 6, and a contact time of 120 min. The Langmuir and Freundlich isotherm models were used to evaluate adsorption isotherms. The maximum adsorption capacity of 281.34 mg/g was observed using the Langmuir isotherm. Furthermore, pseudo-first- and pseudo-second-order and intra-particle diffusion models were used to fit adsorption kinetic data. The pseudo-second-order was best describing the adsorption kinetic with a faster kinetic rate of 0.142 mg g-1 min-1. CFA (coal fly ash) after acidic activation resulted in a slightly higher surface area, average pore volume, and pore size. The maximum breakthrough time and adsorbent saturation time were achieved at initial melanoidin concentration of 1 mol/lit, bed height of 2.5 m, and flow rate of 50 lit/min.

Acute and late complications of organophosphate poisoning.

OBJECTIVE: To describe the acute and late complications of organophosphate (OP) poisoning. STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Medicine Department at Peoples Medical College Hospital, Nawabshah, from June 2008 to December 2009. METHODOLOGY: A total of 300 patients with organophosphate poisoning admitted to the Medical ICU were included. Baseline investigations included blood complete picture, urea, creatinine, arterial blood gas values, and serum cholinesterase levels. Data was retrieved from the files on a structured proforma. Studied variables included gender, mode of exposure, acute (occuring within 4 weeks) and delayed (occuring after 4 weeks onwards) complications RESULTS: There were 50 (16.66%) males and 250 (83.33%) females with ratio of 1:5. Two hundred and forty eight (82.6%) had ingested while 18 (6%) had inhaled the poison. Acute complications included fits in 50 (16.66) bradycardia in 30 (10%) and hyperglycemia in 15 (5%) patients. Delayed complications (after 4 weeks and later) included monoplegia and mild sensory loss of lower limbs in 4 (2.66) and paraplegia and weakness of upper limbs in 2 (0.66%) patients each. A total of 50 patients died due to different complications in acute period making a mortality rate of 16.66%. CONCLUSION: Frequency of acute organophosphate (OP) poisoning complications is much higher and related with high mortality and morbidity and where as late complications are less frequent and less life threatening.