Abstract A review on the preparation of the activated carbon from agricultural waste material is presented. The physical properties such as proximate and ultimate analysis of agricultural waste material were reviewed. The chemical compositions such as cellulose, hemicelluloses and lignin contents were also discussed. The effects of various parameters on the preparation such as carbonization and activation temperature, time, types of activating agents and impregnation ratio were reviewed. Various physical and chemical processes for the activation of the agricultural residues and their effects on the textural properties such as surface area and pore volume were discussed. The low cost, renewable and relatively less expensive of the agricultural waste were found to be efficiently being converted into wealth. The uses of activated carbon derived from agricultural residues in many fields were evidently proven in the review. The reaction kinetic modeling on the pyrolysis and activation of agricultural wastes were also reviewed. � 2015 Elsevier B.V. All rights reserved.

A brief review focusing on preparation of the activated carbon derived from agriculture by-products is presented. The physical and chemical activation of activated carbon were also reviewed. The effects of various parameters including types of activating agents, temperature, impregnation ratio, were also discussed. The applications of activated carbon from agricultural by products were briefly reviewed. It is provenly evident in this review, the relatively inexpensive and renewable resources of the agricultural waste were found to be effectively being converted into wealth materials.

The combination of electrocoagulation with another process is a promising approach to enhance the removal efficiency of water�pollutants. For instance, free radical-assisted electrocoagulation is a new combination showing higher performance. There are different combinations depending on the free radical source. This article reviews free radical-assisted electrocoagulation processes. We discuss electrocoagulation mechanisms; ozone-assisted electrocoagulation processes; advanced oxidation-assisted electrocoagulation processes; and ultrasound-assisted electrocoagulation. We present kinetic models used in free radical-assisted electrocoagulation, scale-up of free radical-assisted electrocoagulation and cost estimation. The major points are: most of the available studies have been done at�laboratory scale with synthetic wastewater, and lack holistic and systematic approaches to consider the process complexity. The performance of the combined process is improved, and the removal efficiency is increased especially with ozone-assisted electrocoagulation, which gives a removal efficiency of more than 95%. The use of ultrasound energy with electrocoagulation is advantageous in reducing the problem of electrode passivation. � 2018, Springer International Publishing AG, part of Springer Nature.

EDLC was fabricated using hybrid solid polymer electrolyte from PVA-diapers and an activated carbon powder as electrode by using solution casting method. For comparison, four types of EDLC cells were constructed and tested. It was found that an EDLC with a PVA-diapers (60:40) polymer electrolyte exhibited much higher capacitance and longer cycle-life. The electrocapacitive properties of the supercapacitor (P50HD50, P60HD40, P70HD30 and P80HD20) were done using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge discharge (GCD). Results from these analysis showed that P60HD40 cell had recorded excellent rate capability and highest Csp value of 179 F g-1 (EIS), 50 F g-1 (CV), 328 F g-1 (GCD) respectively. Futher, results from ESR (GCD) analysis showed that P60HD40 composition of PVA/H3PO4 liquid electroyte gave a lower value of 88.05 ? in the supercapacitor cell compared with another cells.

The microwave digestion method was developed and verified for the determination of arsenic in shrimp paste samples. Experimental design for five factors (HNO3 and H2O2 volumes, sample weight, microwave power and digestion time) were used for the optimisation of sample digestion. For this purpose, two level half factorial design, which involves 16 experiments, was adopted. The concentration of arsenic was analysed by graphite furnace atomic absorption spectrometry. Design Expert� 7.0 software was used to interpret all data obtained. The combination of 2 mL HNO3 and 1 mL H2O2 volumes, 0.1 g sample weight, 1400 W power and 5 min digestion time was found to be the optimum parameters required to digest the shrimp paste samples. Tests with spiked samples presented good recoveries with relative standard deviations between 0.32% and 5.35%. � 2012 Elsevier Ltd. All rights reserved.

Sample preparation using microwave assisted digestion has been a well-known procedure worldwide. Nowadays, experimental designs have been used to facilitate this process. This study uses factorial design approach to study the concentration of copper in shrimp paste sample. The aim of the study was to optimize the digestion procedures for digesting the shrimp paste samples. Flame atomic absorption spectrometry was used to study the copper concentration. DOE software-Design Expert�7.0 was used to interpret all the data obtained. The combination of 4 mL HNO3, 2 mL of H2O2, 0.1 g of sample weight, 1400 W of power and duration of 5 min were found to be optimum in digesting shrimp paste sample for copper analysis.

This study investigates the effect of temperature and impregnation ratio on the physicochemical properties of activated carbon prepared from desiccated coconut residue by chemical activation using potassium hydroxide. Desiccated coconut residue sample was first carbonized at three different temperatures for 1 h at 400, 500 and 600 °C, respectively. The resulting chars were impregnated with KOH at three different impregnation ratio; 1:1, 1:2 and 1:3, respectively and activated under nitrogen atmosphere for 1 h at three different temperatures based on its carbonization temperature. The BET surface area and pore volume was strongly affected by temperature in which increased in temperature caused increased in BET surface are and pore volume. The BET surface area also increased with impregnation ratio but then decreased due to pore widening of activated carbons.