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Assam coal was reductively acylated by using zinc dust, acetic acid and phenol. This reaction resulted in enhanced extractability of coal in quinoline. The residue extracted after the first step was further reductively acylated which rendered it further extractable in quinoline. Three successive steps could solubilize the coal to the extent of 58 per cent on ash balance basis.

This Paper reports studies on the depolymerization reaction of Assam coal using p -toluenesulphonic acid (PTS) in phenol. Attempts have been made to determine the true extractability of coal by depolymerization by balancing the mineral matter present in the original coal with that in the residual depolymerized coal after extraction, and thus allow for the addition of phenol to the coal. The factors that could lead to a reduction in the amount of catalyst and reaction time required for depolymerization were studied. Three successive depolymerization reactions, followed by extractions in benzene/methanol (7:3 vol/vol), allowed the extraction of ≈50% coal with a coal:catalyst (PTS) ratio of 2:1. The particle size of the coal also affected the depolymerization reaction. Smaller coal particles (− 60 to + 120 BSS mesh, 250-125 gmm) resulted in a better extraction (60% in benzene/methanol (7:3 vol/vol)) compared with larger particles. The depolymerization reaction was found to be under diffusion and chemical control within the coal particle. Exposure of active sites in coal through extraction, increase in surface area through size reduction, chemical pretreatments, use of promoters and elevated temperatures should help to increase the rate of the depolymerization reaction.

Assam coal was alkylated with iso propyl and n -butyl bromides and AlCl 3 catalyst in CS 2 and quinoline as solvents. This resulted in enhanced extraction of coal in quinoline. Alkylation with n -butanol and dry HCl gas also resulted in enhancement of the extractability in quinoline. The increase in extractability was found to be greater than that observed in the case of AlCl 3 -catalysed butylation. The coal was also amylated with iso amy alcohol and dry HCl gas and then alkylated using a p -toluenesulphonic acid catalyst in n -butanol or iso amyl alcohol. In this case the increase in quinoline extraction yield was greater still. n -Butanol was a better alkylating agent than iso amyl alcohol in all cases. The coal could also be alkylated in its plastic state using cetanol without any catalyst. Alkylation rendered > 50% of the coal extractable in quinoline.

Carboxylic acids, acid anhydrides and N-hydroxy methylamides were used to acylate Assam coal under Friedel—Crafts reaction conditions. This reaction resulted in the enhancement of the extractability of coal in benzene—methanol (7:3 vol./vol.) and quinoline after acylation with carboxylic acids and acid anhydrides. The effect of catalyst (AlCl3) concentration on reaction was also investigated. l.r. spectra of reaction products indicated the introduction of acyl groups in the coal structure. Phthalimidomethylation could render about 50% coal extractable in quinoline.

Depolymerization of coals is an important reaction for the study of coal structure. Coal is depolymerized by using p-toluenesulphonic acid in phenol. Depolymerization takes place mainly through the cleavage of C-C and C = bonds and subsequent phenolation, whereas C-O-C linkages of coal are not affected by this treatment. In the present work, reactions, such as, reduction of coal through Li in ethylene-diamine, alkaline-degradation and dry HCl gas, which are known to cleave C-O-C linkages in coal selectively, have been coupled (as a pre-treatment) with depolymerization reactions. This could enhance the yields of low molecular weight products from coal as revealed by the enhancement in the benzene-methanol (7/3 vol/vol) extractability of depolymerized coals. The use of Ce(IV) salt, benzoyl peroxide, lead tetra-acetate and potassium persulphate, promotes the depolymerization reaction to low molecular weight products. These studies help in understanding the mechanism of generation of asphaltenes and, thereby, might help in the studies of liquefaction of coal.

Previous work showed that the solvent extraction yield of coal increased as a result of chemical reactions such as formylation, reductive acylation, acylation, amidomethylation, alkylation, reduction and depolymerization. In the work described in this Paper, dmmf coal obtained after demineralization with mixed HF-HCI acids was used for solvolytic extraction studies after depolymerization, alkylation, acylation, amidomethylation, reductive acylation and reduction reactions. In comparison with the original coal, mineral matter free coal showed less increase in extractability as a result of these reactions indicating that mineral matter present in the original coal was acting as a promoter for these reactions.

WOS: 000376443500008, PubMed ID: 27223147, BACKGROUND The development of neutralizing anti-factor VIII alloantibodies (inhibitors) in patients with severe hemophilia A may depend on the concentrate used for replacement therapy. METHODS We conducted a randomized trial to assess the incidence of factor VIII inhibitors among patients treated with plasma-derived factor VIII containing von Willebrand factor or recombinant factor VIII. Patients who met the eligibility criteria (male sex, age = 5 Bethesda units). Inhibitors developed in 29 of the 125 patients treated with plasma-derived factor VIII (20 patients had high-titer inhibitors) and in 47 of the 126 patients treated with recombinant factor VIII (30 patients had high-titer inhibitors). The cumulative incidence of all inhibitors was 26.8% (95% confidence interval [CI], 18.4 to 35.2) with plasma-derived factor VIII and 44.5% (95% CI, 34.7 to 54.3) with recombinant factor VIII; the cumulative incidence of high-titer inhibitors was 18.6% (95% CI, 11.2 to 26.0) and 28.4% (95% CI, 19.6 to 37.2), respectively. In Cox regression models for the primary end point of all inhibitors, recombinant factor VIII was associated with an 87% higher incidence than plasma-derived factor VIII (hazard ratio, 1.87; 95% CI, 1.17 to 2.96). This association did not change in multivariable analysis. For high-titer inhibitors, the hazard ratio was 1.69 (95% CI, 0.96 to 2.98). When the analysis was restricted to recombinant factor VIII products other than second-generation full-length recombinant factor VIII, effect estimates remained similar for all inhibitors (hazard ratio, 1.98; 95% CI, 0.99 to 3.97) and high-titer inhibitors (hazard ratio, 2.59; 95% CI, 1.11 to 6.00). CONCLUSIONS Patients treated with plasma-derived factor VIII containing von Willebrand factor had a lower incidence of inhibitors than those treated with recombinant factor VIII. (Funded by the Angelo Bianchi Bonomi Foundation and others; ClinicalTrials.gov number, NCT01064284; EudraCT number, 2009-011186-88.), Angelo Bianchi Bonomi Foundation, Funded by the Angelo Bianchi Bonomi Foundation and others

BACKGROUND: Patients with severe hemophilia A and factor VIII inhibitors are at increased risk for serious bleeding complications and progression to end-stage joint disease. Effective strategies to prevent bleeding in such patients have not yet been established. METHODS: We enrolled patients with hemophilia A who were older than 2 years of age, had high-titer inhibitors, and used concentrates known as bypassing agents for bleeding in a prospective, randomized, crossover study comparing 6 months of anti-inhibitor coagulant complex (AICC), infused prophylactically at a target dose of 85 U per kilogram of body weight (±15%) on 3 nonconsecutive days per week, with 6 months of on-demand therapy (AICC at a target dose of 85 U per kilogram [±15%] used for bleeding episodes). The two treatment periods were separated by a 3-month washout period, during which patients received on-demand therapy for bleeding. The primary outcome was the number of bleeding episodes during each 6-month treatment period. RESULTS: Thirty-four patients underwent randomization; 26 patients completed both treatment periods and could be evaluated per protocol for the efficacy analysis. As compared with on-demand therapy, prophylaxis was associated with a 62% reduction in all bleeding episodes (P