Most pre-Quaternary palynology samples are currently prepared by demineralization of the sediment/sedimentary rock matrix using hydrochloric and hydrofluoric acids (HCl and HF respectively). If a consistently effective alternative to this procedure can be developed, palynological processing will be made significantly less hazardous to both laboratory personnel, and to the wider environment. Furthermore, most non-acid processing methods are normally quicker and cheaper than matrix dissolution using acid. Some authors have previously used hydrogen peroxide (H₂O₂) to extract palynomorphs by the physico–chemical disaggregation of the clay fraction. However, H₂O₂ is a powerful oxidizing agent and hence can potentially destroy sedimentary organic material, including palynomorphs. A new method using hot H₂O₂, where exposure of the sample material to the H₂O₂ is minimized, has been developed. Crushed sample material in a suitable vessel is placed on a hot plate for one minute, treated with 15–30% H₂O₂ for 10 minutes, then the residue is diluted with cold distilled water. Disaggregated sample material tends to float, and is decanted into a large vessel containing distilled water to further dilute the H₂O₂. If any undisaggregated sample remains, the procedure is repeated several times if necessary. Relatively indurated sedimentary lithotypes normally require several treatments. The reason for this stepwise treatment is that the organic material is not exposed to H₂O₂ for sustained periods, thereby reducing the possibility of palynomorph damage/degradation due to oxidation. When the sample matrix has been fully disaggregated, the residue can be further processed as appropriate.

In this study, eight samples of Carboniferous, Jurassic, Paleogene, and Quaternary age were prepared quantitatively using the new H₂O₂ method. These were all prepared using 30% H₂O₂. For comparison, they were also prepared quantitatively using HCl/HF and/or sodium hexametaphosphate [(NaPO₃)₆]. Quantitative preparations allow the concentration of palynomorphs extracted to be determined, and therefore the effectiveness of the techniques used can be compared objectively. The palynomorph residues derived from these three techniques varied markedly. The H₂O₂ method does not consistently disaggregate all the sample material, particularly the older and more indurated lithotypes. Some evidence of oxidation effects was observed. Two samples of Mississippian mudstone from the U.S.A. were prepared using H₂O₂ and (NaPO₃)₆. Both methods produced abundant miospores, however the H₂O₂ procedure yielded far higher palynomorph concentrations than the (NaPO₃)₆ technique. Minor degradation of palynomorphs in the H₂O₂ preparation was noted. The H₂O₂ and HCl/HF methods were compared directly on a palynomorph-rich sample of Upper Carboniferous mudstone from offshore Scotland. Both preparations produced abundant miospores. The HCl/HF method had significantly higher recovery levels than the H₂O₂ procedure. It appears that the H₂O₂ method simultaneously macerates the matrix, and oxidizes any amorphous organic material (AOM) present. In this sample, the HCl/HF residue was relatively rich in AOM. By contrast, the H₂O₂ preparation is virtually clear of this phytoclast type, which partially obscures palynomorphs. Two samples of the Middle Jurassic Grantham Formation of eastern England were processed using H₂O₂ and HCl/HF. The two methods produced abundant palynofloras of similar palynomorph conc