Oxidative pyrolysis combined with the microwave-assisted extraction method for the multi-elemental analysis of boron carbide powders by inductively coupled plasma optical emission spectrometry (ICP-OES)

Abstract

A method based on oxidative pyrolysis (OP) using an in-house quartz chamber in combination with microwave-assisted extraction (MAE) was developed as a new sample preparation approach for the determination of metallic impurities in boron carbide powders. Initially, a known amount of boron carbide powder (100-400 mg) was weighed into a quartz boat, which was inserted in the pyrolysis chamber. The chamber was heated to $500 C by means of a Bunsen burner in the presence of an oxygen stream. The heating was continued until the burning process was completed. After this step, the chamber was allowed to cool to room temperature and the boat was taken out. Subsequently MAE was applied with an extractant mixture of 10 mL of 30% HNO 3 + 10% HCl + 5% HF using the optimized microwave program (microwave power: 1200 W, ramp: 10 min, temperature: 200 AE 5 C, hold: 10 min).After completion of the extraction process, the supernatant was separated from the undissolved residues by centrifugation for 4 min at 5000 rpm. A known volume of the clear supernatant was transferred to another pre-cleaned tube and diluted to the required volume for subsequent step of analysis of W, Si, Pb, Ni, Fe, Ca, Mg, Ti and Al by an inductively coupled plasma optical emission spectrometer (ICP-OES). Parameters affecting the recoveries of the metals of interest with the proposed combined approach were investigated. The sodium carbonate fusion method was adopted for crossvalidation of the results of the proposed OP-MAE method. The detection limits obtained were significantly lower than those of the fusion method. The results obtained have proven the suitability of the developed combined approach as a sensitive sample preparation methodology for the determination of metallic impurities in boron carbide powder samples.

An integrated approach based on oxidative pyrolysis and microwave-assisted digestion for the multi-elemental analysis of coal samples by ICP-based techniques

“…The choice of these conditions was based on the results obtained in our previous work [45]. The procedure for each runs involved oxidative pyrolysis and MWD followed by ICP-OES/ICP-MS analysis for elements of interest.…”

“…These green concepts are the driving force for the current research toward development of new analytical methods. In this laboratory, oxidative pyrolysis set-up has been successfully applied for the rapid determination of mercury in organic rich materials and for the multi-elemental analysis of boron carbide powders [44,45]. More recently the in-house set-up was successfully utilized for the analysis of boron in graphite powders [46].…”

Development of a microwave-assisted digestion method for the rapid determination of chloride and fluoride in nuclear-grade boron carbide powders

“…39 More recently, oxidative pyrolysis combined with the microwave-assisted extraction method for the determination of metallic impurities in boron carbide powder samples has also been reported by authors from the same laboratory. 40 However, simultaneous extraction of Cl and F using microwave technology from a boron carbide matrix has not been well explored. The present investigation therefore explores the feasibility of separating Cl and F together from a boron carbide matrix, employing an MAD technique by optimizing various parameters with the use of a high pressure microwave glass vessel and a domestic microwave oven and their subsequent determination using an ion-selective electrode.…”

Development of Oxidative Pyrolysis Method for the Rapid Determination of Boron in Graphite Powders by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)

“…In this study, a new sample preparation method based on oxidative pyrolysis (OP) has been developed for this purpose. In our previous investigations, the OP approach has been successfully utilized for the determination of mercury in organic-rich solid materials and for the multi-elemental analysis of boron carbide samples (32,33).…”