Apiezon L-grease

Non-polar hydrocarbon-type liquid phases, e.g. paraffin oil(Nujol), squalane, Apiezon L grease and silicone-gum rubber the latter is used for high-temperature work (upper limit 400°C). 

The separation was achieved on an Apiezon L grease SCOT glass capillary column. Complete separation of six dinitrobenzene isomers took 8 min. 

The stationary phases used were present to 20% w/w extent on acid-washed Silicel C-22 firebrick 60-85 mesh the liquids used were (i) polyethylene glycol 400, (ii) dinonyl phthalate, (iii) tritolyl phosphate, (iv) squalane and (v) Apiezon L grease. Great care was taken to ensure that no moisture was present on the liquid phase or support. 

Table 153. Specific Retention Volumes (V ) and Relative Retentions (a) of Arenetricarbonylchromi m Complexes on SE-30 and Apiezon L Greases...

Pyrazolines Imidazoles Thiazoles Oxadiazoles 1 -Phenylpyrazoles Purines Dioxolanes Ox azolines 10% Cyanethylated mannite on Celite 545. 5% OV-17 on Chromosorb W, AW-DMCS (H.P.). Carbowax 4000, dioleate on firebrick, 190 °C. Silicone grease on Chromosorb P. Apiezon L on firebrick C-22, 220 °C. 15% Hallcomid M-18 on firebrick. Carbowax 20M on Gas-Chrom P. Ethyleneglycol succinate on Diatoport-S. 

Elemental mass distribution - The aerosol sampled by the LPI for elemental analysis was impacted on coated mylar films affixed to 25 mm glass discs. The mylar had been coated with Apiezon L vacuum grease to prevent particle bound. The LPI samples were sent to Crocker Nuclear Laboratory for elemental analysis by PIXE using a focused alpha particle beam of 3 to 4 mm diameter. Nanogram sensitivities for most elements were achieved with the focused beam. A detailed description of the PIXE focused beam technique applied to LPI samples can be found in Ouimette (13). Based upon repeated measurements of field samples, the estimated measurement error was about 15-20% or twice the minimum detection limit, whichever was larger. 

Sampling. Four aerosol samples were collected isokinetically on July 26, 1979, at ports on the inlet duct of the ESP at Plant A two were taken with 62-mm fluoropore filters and two were taken with the University of Washington MKV Cascade impactor (1 ). At plant D, samples were collected over a 6-day period at ports both in the outlet duct of the ESP (i.e., upstream of the FGD system) and at the 91-m level of the stack. Eleven fluoropore filter, 1 MKV, and 4 MKIII impactor samples at each location, giving a total of 22 filter, and 8 MKIII samples. A single MKV sample was also collected in-stack at reduced pressure at plant D during the 6-day period. Polycarbonate material coated with apiezon L vacuum grease and 62 or 47-mm-diam, l-pm pore Fluoropore filters were used as back-up filters in the MKV impactor. 

Apiezon Z is a hydrocarbon grease which is used for the separation of barbiturates. It has the advantage over the silicone phases that it is stable when coated with alkali to reduce the tailing of strongly basic compounds. The amphetamines may be separated on a column of 10% Apiezon L with 2% potassium hydroxide. 

Fig. 8.—Separation of Alditol Acetates. (Key (A) tetra-O-acetylerythritol (B) penta-0-acetylribitol (C) penta-0-acetylxylitol (D) hexarO-acetjdallitol (E) hexa-0-acetyl-D-iditol (F) hepta-O-acetyl-meso-jij/cero-ollo-heptitol (G) hepta-O-acetyl-D-(//j/cero-D-monno-heptitol (H) hepta-O-acetyl-n-jlycero-D-ffluco-heptitol and (I) octa-0-acetyl-D-erylAro-L-po/ocIo-octitol. Conditions column (120 x 0.5 cm.) of a 1 1 (v/v) mixture of the two following packings (1) 1 1 (w/w) mixtures of (a) 20% w/w butane-diol succinate on Chromosorb W, 60-80 mesh, and (b) 20% w/w Apiezon M grease on silver-coated Chromosorb W, 60-80 mesh, with (2) 0.3% w/w Apiezon M grease on silver-coated glass-beads, 60-plus mesh 213° 200 ml. of argon/min. /3-ionization detector.)...

Particle bounce can be effectively controlled by coating an adhesives layer on the collection surface to keep collected particles from bouncing off the plates. Typical coating materials include Antifoam A, Hi-Vac silicone grease, Apiezon L, viscous oils, Vaseline, and glycerin. The typical thickness of the adhesive... 

G44 2% Low molecular-weight petrolatum hydrocarbon grease and 1% solution, of KOH Apiezon L 4-1% KOH... 

---