Recovery achievable

To find the optimum design it will be necessary to cost a number of alternative designs, seeking a compromise between the capital costs, determined by the number and size of the exchangers, and the utility costs, determined by the heat recovery achieved. 

Fig. 11.10 Concentration recovery on the haptoglobin assay, (a) The recovered concentration against the applied concentration, (b) The precision of recovery, achieving 80% recovery over a dynamic range of 1,000 1...

Analysis was performed on an ES-Ovomucoid column for stereoselectivity assessment, and for MS/MS, an X-Terra MS C18 column (2.1 x 100mm, 5 fan) was used. Figure 1.17 shows the wash and elution fractions from the SPE in a 384-well plate. The SPE conditions evaluated are listed in the table below the figure. The binding of the drug to the affinity sorbent in a 96-well plate was less efficient than the 384-well plate because the sorbent formed a disk on the former and a column on the latter. The efficiency is reflected in the >95% recoveries achieved with the 384-well format. 

Unlike PSA air separation the adsorbents used in hydrogen purification are not limited to zeolite molecular sieves. Garbons and silica gel are used in many PSA installations. Zeolites are used for obtaining certain critical specifications where the nature of the isotherms that they possess helps in recovery, achieving purity and minimizing bed size factors. 

The overall sulfur recovery achievable by the recycle Selec-tox process increases with higher H2S concentration and with the number of catalystic stages used. Vfe may expect 94 to 95 percent recovery from 10 percent H2S feed with three catalystic stages ... 

Vanillin in MeOH and sulphuric acid was used for the derivatization of MON. Chicken tissue (muscle, liver, skin with adhering fat tissues) samples were homogenized with MeOH-water, NaCl was added to the supernatants, and MON was isolated and concentrated by liquid-liquid partition carbon tetrachloride and by SPE on the silica gel. Standard recoveries ranged from 82% to 96%. The method is specific for MON in the presence of closely related PETs— NAR and SAL. Lasalocid and other antibiotics, such as tylosin, nicarbazin, bacitracin, lin-comycin, and bambermycin, do not react in the system and therefore do not interfere (102). A similar method was also used for the determination of MON in bovine tissues and milk. The homogenization of milk was performed by using MeOH. Recoveries achieved were 79-88% with RSD values of 4.6-9.1% (103). 

A similar method was used for the determination of DIHS in kidney and meat from cow and swine. The derivatives were formed using l,2-naphthoquinone-4-sulphonic acid (NQS) in NaOH. The temperature of the derivatization was lower (40°C) in comparison to the method described earlier. Recoveries achieved were 73.2-73.5% for kidney and 80.0-82.9% for muscle (for only two concentration levels), with RSD of 1.5-3.1% and 0.3-1.3%, respectively. After STR was added to the sample, the baseline resolution of the two drugs was not achieved (113). 

A method capable of quantifying SPC in raw bovine milk was developed. In this procedure the sample was centrifuged at -4°C and the top fat layer removed. The defatted milk was depro-teinated with TCA, and the supernatant was washed sequentially with dichloromethane, hexane, and ethyl acetate. An aliquot of the separated aqueous layer was prepared for the HPLC analysis by mixing with DSA and filtering. The analyte was quantified with an electrochemical detector. Recoveries achieved were 76-80% (116). 

A more difficult preseparation technique was used for the determination of TLM in ovine milk, combining several LLE procedures. Tilmicosin was extracted from milk into MeOH and acidified, and nonpolar coextractives were removed using hexane followed by carbon tetrachloride. pH was adjusted to 9.0, and TLM was partitioned into chloroform. Recoveries achieved were 84.3-104.8%, with RSD values of 6.6-12.9% (126). 

Figure 7. Plot of the relative increase in recovery achieved as a function of the PAH fused ring number as follows 70 vs. 0% dead volume 1 1 vs. 1 20 cell dimensions 100 vs. 75°C and 0.75 vs. 0.50 g/ml.

According to the halophilic approach, all the purification steps are performed in high salt concentrations. The advantage of this approach is the high level of recovery achieved in each step. This ap-... 

The purification of liprotein lipase (LPL) from rat adipose tissue [84] and hen adipose tissue [85], respectively, has been described using an affinity column prepared by insolubilization of heparin on agarose. In the case of hen adipose LPL elution was achieved with 1.16 M NaCl and 50% recovery achieved with 80-fold purification. 

Some abuse drugs have been extracted from urine by SFE [viz. cocaine and its metabolites (134) and amphetamine and methamphetamine (135). In the first instance, the levels measured using SFE showed analyte recovery better than 70% for cocaine, better than 40% for benzoylecgonine, and better than 85% for ecgonine methyl ester from whole blood and urine. The limits of detection and quantitation were 1 and 10 ng, respectively, based on a 200-pL sample. Regarding amphetamine (AP) and methamphetamine (MA), an in situ SFE and chemical derivatization procedure followed by GC-isotope dilution mass spectrometry in urine was described. The mean recoveries achieved were 95% (RSD = 3.8%) for AP and 89% (RSD = 4%) for MA. The calibration graphs were linear within 100-500,000 ng/mL, varying the limits of detection and quantitation from 19 to 50 and from 21 to 100 ng/mL, respectively. 

Prior to the determination, laboratories were also required to optimise analytical methodologies to ensure the quality of the data produced. In particular, the percentage recovery achieved for each of the certified OCPs had to be stabilised. 

The recoveries achieved with this procedure are shown in Table III. 

The sorbent materials most commonly used for the extraction of phthalate esters from water are C-18 and polymeric phases based on PS-DVB. Recently, a new polymeric phase. Oasis, has been applied for the concentration of phthalates, but the recoveries achieved with these polymers were lower than those obtained with C18. ° Nevertheless, this extracting phase was suitable for the extraction of phthalate metabolites from biological fluids. 

Brossa et al. developed an automated SPE-GC-MS method for the determination of endocrine disrupting compounds including six phthalate esters. The interface device was a programmed temperature vaporizer (PTV), whose liner was packed with Tenax. The samples were spiked with 50% of methanol and 15 ml of this mixture were preconcentrated. Before elution, the precolumn was dried with nitrogen. The analytes were desorbed in the backflush mode with three ethyl acetate fractions of 100 /rl and online transferred to the GC system. The performance of the method was tested with several environmental water samples. The recoveries achieved were satisfactory and the detection limits were between 1 to 36 ng/1. 

Limits of Detection. Since the clean-up and recovery achieved in the overall sample workup effects the detection limit of the measurement technique, the actual limit of detection is, relative to the amount of sample available for analysis, always less than the limit of the measurement technique. Thus, if a measurement technique can respond to one microgram of material, but the recovery in the preliminary sample workup is 50%, then the true effective detection limit is two micrograms, and it is this latter value that must be reported. Additionally, the limit of detection of the measurement technique must be taken as not the smallest amount causing a response, but rather the smallest amount to which the analytical criteria employed for qualitative identification can be applied. 

As an alternate process on direct reduction smelting of sea nodules is developed at CSIR-NML to recover Cu, Ni and Co in the form of alloy with about 90% recovery, achieve good result. Using 8 % coke 4 % quartz, 90.4% Cu, 91.7% Ni, 87.8% Co reeoveries were achieved on pilot scale. As a part of iron was recovered in the alloy, the process generate a slag rich in manganese with Mn/Te ratio of about 10, from whieh standard grade Fe-Si-Mn was produced. The metal rieh alloy was further processed to recover Cu, Co and Ni in pure form. 

Proper sampling procedures have to be applied to obtain representative samples from analyzed biological material since mycotoxins are not homogenously distributed in contaminated grain stocks. Sample preparation usually involves a few cleanup steps to eliminate compounds present in the matrix that might coelute with the mycotoxins. The cleanup methods may involve either liquid-liquid extraction (LLE), solid-phase extraction (SPE) on columns that contain various types of solid phases, or immunoaffinity columns [39,42,43]. The recovery achieved with a cleanup method is critical for the final results. 

Early classical extraction methods for PAs were applied without much consideration of the range of chemical structures of the alkaloids and in particular were not optimized to obtain the maximum yields of both the tertiary and oxide forms. In fact few publications even today describe the recovery achieved with the extraction procedure used. PAs have either a reduced tertiary nitrogen atom with a characteristic basic function or an oxidized form (PANO). Both forms have little solubility in non-polar solvents such as hexane and are best extracted with polar solvents such as methanol or with aqueous dilute acid. These solvents dissolve both the PAs and the PANOs with relative ease. 

The smelter primarily makes a return from the treatment charge, plus any free metals derived from recoveries achieved for lead and precious metals above the recoveries implied in the terms. For instance it may be possible to achieve 98 per cent lead recovery, giving three per cent free metal. Silver and gold recoveries may also significantly exceed the terms values, depending on process efficiencies. 

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