Abstract: The invention relates to a process for purifying crude aromatic nitro compounds which originate from the nitration of aromatic compounds, comprising the single or multiple performance of the following wash stage (a): (a) contacting the crude aromatic nitro compound (N-in) with an aqueous phase (W-res) and then separating the phases to obtain an organic phase (N-res) and an aqueous phase (W-res), wherein at least one demulsifier (D) is present in one or more of the wash stages (a).

Abstract: The invention relates to a process for purifying crude aromatic nitro compounds which originate from the nitration of aromatic compounds, comprising the following wash stages (a1) and (a2), where each of stages (a1) and (a2) may be performed once or more than once in succession: (a1) contacting the crude aromatic nitro compound (N1-in) with a first aqueous phase (W1-in) comprising at least one base (B) and then separating the phases to obtain an organic phase (N1-res)and an aqueous phase (W1-res); and then (a2) contacting the organic phase (N1-res) obtained in stage (a1) with a second aqueous phase (W2-in) and then separating the phases to obtain a purified organic phase (N2-res) and at least one aqueous phase (W2-res), the aqueous phase used (W2-in) having a pH of 6 to 9.

Abstract: A process for the preparation of low-solvent alkyl diketenes of the general formula: ##STR1## in which R.sup.1 denotes C.sub.10 -C.sub.30 alkyl or C.sub.10 -C.sub.30 alkenyl andR.sup.2 denotes hydrogen or C.sub.1 -C.sub.8 alkyl, by causing carboxylic chlorides of the formula II ##STR2## in which R.sup.1 and R.sup.2 have the aforementioned meanings, to react with tertiary amines of the formula III ##STR3## in which R.sup.3, R.sup.4, R.sup.5 denote C.sub.1 -C.sub.12 alkyl or C.sub.3 -C.sub.12 cycloalkyl andR.sup.3 and R.sup.4 together denote a C.sub.2 -C.sub.11 alkylene dichain optionally interrupted by oxygen or nitrogen,in a substantially water-immiscible, inert solvent, wherein distillation is carried out at temperatures ranging from 80.degree. to 130.degree. C. and pressures ranging from 10 to 500 mbar and subsequently with the addition of water or steam.