Parr digestion bombs

Inorganic and organic materials can be dissolved rapidly in Parr acid digestion bombs with Teflon liners and using strong mineral acids, usually nitric and/or aqua regia and, occasionally, hydrofluoric acid. Perchloric acid must not be used in these bombs due to the high risk of explosion. 

Table 14.7 Microwave digestion bombs supplied by Parr Instruments...

Decomposition in closed Teflon vessels at high pressure (up to 85 bar) with microwave heating. (Microwave Acid Digestion Bomb, Parr Instrument Company, USA.)... 

Figure 28-8 Microwave digestion bomb lined with Teflon. The outer container retains strength to 150°C but rarely reaches 50°C. [Courtesy Parr Instrument Co.. Moline. ILJ...

Parr Bombs. Two types of Parr bombs were used. The acid digestion bombs were used for the ash dissolutions. About 0.2 g of shale or ash was dissolved in 3 mL aqua regia and 2 mL HF in the acid digestion bomb and heated at 110°C in an air-oven for two hours. After the dissolution, 1 g of boric acid was added to each sample solution, which was heated on a water-bath... 

Parr Bomb Dissolution of Shales. Originally the acid digestion bomb was developed by Bernas (14) for the dissolution of silicate matrices. An adaptation of this bomb is now marketed by Parr Instrument Company of Moline, Illinois. The dissolution procedure has been adapted to shales and was described in the Experimental Section. 

Element wt % Lithium Tetraborate Fusion Parr Acid No Ashing Digestion Bomb Preashing... 

Model 4745 acid digestion bomb, Parr Instrument Co., 211 Fifty-Third... 

Figure 2-18 Microwave digestion bomb lined with Teflon. [Parr Instrument Co., Moline, IL] A typical 23-mL vessel can be used to digest as much as 1 g of inorganic material (or 0.1 g of organic material, which releases a great deal of gaseous CO2) in as much as 15 ml of concentrated acid. The outer container maintains its strength up to 150°C, but rarely rises above 50°C. If the internal pressure exceeds 80 bar, the cap deforms and releases the excess pressure.

Seven of the artifacts from the La Scola site were analyzed by ICP-MS. Samples were ultrasonically cleaned and dried, and then pulverized at liquid nitrogen temperatures using a SPEX 6700 freezer mill. 100 mg of the powdered sample were mixed with 0.2 mL aqua regia and 2.5 mL hydrofluoric acid and dissolved in a Parr acid digestion bomb at 120 °C for 2 hours. Samples were then diluted to a total volume of250 ml so that elements of interest would be present at concentrations of 500 ppb or less. 

Another method may be employed to reduce the particle sizes of the starting materials, thereby increasing their reactivity. Stoichiometric quantities of the reagents are first heated at 923 K for 1 h to decompose the nitrates. The resulting mixture, corresponding to 1 mmol of product, and 1.5 mL of 20% NH OHlaq) (Baker, ultrapure, ULTREX) are placed in a 23-mL Teflon container and heated in a Parr 4745 digestion bomb at 393 K for 16 h. The lid... 

Serum blood, and urine Filtration of sample if needed blood requires digestion in a Parr bomb dilution of serum or urine with acid or water ICP/AES 10-50 pg/L 85 (serum) >80 (urine, blood) Que Hee and Boyle 1988... 

Aspila et al. [60] have described a semi-automated method for the determination of inorganic, organic and total phosphorus in river and lake sediments. Total phosphorus is extracted from sediments with 1M hydrochloric acid after ignition at a high temperature (550°C) (method 1) or by digestion with sulphuric acid-potassium persulphate at 135°C in a sealed PTFE-lined Parr bomb (method 2). 

Que Hee and Boyle [70] analysed soils for total phosphorus using Parr bomb digestion with hydrofluoric-nitric-perchloric acids followed by inductively coupled plasma atomic emission spectrometry. 

Digestion of organic material is classified as either dry ashing, when the procedure does not include liquid, or wet ashing, when liquid is used. Occasionally, fusion with Na202 (called Parr oxidation) or alkali metals may be carried out in a sealed bomb. Section 27-4 discussed combustion analysis, in which C, H, N, S, and halogens are measured. 

Human blood, urine, serum, feces Acid digestion using Parr bomb technique, microwave, or hot plate method ICP-AES 1 g/L > 75% Que Hee and Boyle 1988... 

Adequate digestion methods are important in the determination of all metals, including aluminum. Que Hee and Boyle (1988) showed that Parr bomb digestions were always superior to hot plate digestions for many elements, including aluminum, in feces, liver, and testes. Microwaving in closed vessels produced lower aluminum recoveries in liver than Parr bomb digestions. The Parr bomb values for citrus leaves were within 5% of the NBS certified values. 

Rock, magma, soil, paint, citrus leaves Acid digest sample using Parr bomb or microwave ICP-AES 0.001 g/L 90% Que Hee and Boyle 1988... 

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